Patent Publication Number: US-2020302187-A1

Title: Method, apparatus, and system for people counting and recognition based on rhythmic motion monitoring

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application is related to U.S. patent application with attorney docket number PIP506049, entitled “METHOD, APPARATUS, AND SYSTEM FOR VITAL SIGNS MONITORING USING HIGH FREQUENCY WIRELESS SIGNALS,” filed on May 10, 2020, which is expressly incorporated by reference herein in its entirety. 
     The present application hereby incorporates by reference the entirety of the disclosures of, and claims priority to, each of the following cases:
         (a) U.S. patent application Ser. No. 15/326,112, entitled “WIRELESS POSITIONING SYSTEMS”, filed on Jan. 13, 2017,
           (1) which is a national stage entry of PCT patent application PCT/US2015/041037, entitled “WIRELESS POSITIONING SYSTEMS”, filed on Jul. 17, 2015, published as WO 2016/011433A2 on Jan. 21, 2016,   
           (b) U.S. patent application Ser. No. 16/127,151, entitled “METHODS, APPARATUS, SERVERS, AND SYSTEMS FOR VITAL SIGNS DETECTION AND MONITORING”, filed on Sep. 10, 2018,
           (1) which is a continuation-in-part of PCT patent application PCT/US2017/021963, entitled “METHODS, APPARATUS, SERVERS, AND SYSTEMS FOR VITAL SIGNS DETECTION AND MONITORING”, filed on Mar. 10, 2017, published as WO2017/156492A1 on Sep. 14, 2017,   
           (c) U.S. patent application Ser. No. 16/125,748, entitled “METHODS, DEVICES, SERVERS, APPARATUS, AND SYSTEMS FOR WIRELESS INTERNET OF THINGS APPLICATIONS”, filed on Sep. 9, 2018,
           (1) which is a continuation-in-part of PCT patent application PCT/US2017/015909, entitled “METHODS, DEVICES, SERVERS, APPARATUS, AND SYSTEMS FOR WIRELESS INTERNET OF THINGS APPLICATIONS”, filed on Jan. 31, 2017, published as WO2017/155634A1 on Sep. 14, 2017,   
           (d) U.S. patent application Ser. No. 15/861,422, entitled “METHOD, APPARATUS, SERVER, AND SYSTEMS OF TIME-REVERSAL TECHNOLOGY”, filed on Jan. 3, 2018,   (e) U.S. patent application Ser. No. 16/200,608, entitled “METHOD, APPARATUS, SERVER AND SYSTEM FOR VITAL SIGN DETECTION AND MONITORING”, filed on Nov. 26, 2018,   (f) U.S. Provisional Patent application 62/846,686, entitled “METHOD, APPARATUS, AND SYSTEM FOR WIRELESS INERTIAL MEASUREMENT”, filed on May 12, 2019,   (g) U.S. Provisional Patent application 62/846,688, entitled “Method, Apparatus, and System for Processing and Presenting Life Log based on a Wireless Signal”, filed on May 12, 2019,   (h) U.S. Provisional Patent application 62/849,853, entitled “Method, Apparatus, and System for Wireless Artificial Intelligent in Smart Car”, filed on May 18, 2019,   (i) U.S. patent application Ser. No. 16/446,589, entitled “METHOD, APPARATUS, AND SYSTEM FOR OBJECT TRACKING AND SENSING USING BROADCASTING”, filed on Jun. 19, 2019,   (j) U.S. Provisional Patent application 62/868,782, entitled “METHOD, APPARATUS, AND SYSTEM FOR VITAL SIGNS MONITORING USING HIGH FREQUENCY WIRELESS SIGNALS”, filed on Jun. 28, 2019,   (k) U.S. Provisional Patent application 62/873,781, entitled “METHOD, APPARATUS, AND SYSTEM FOR IMPROVING TOPOLOGY OF WIRELESS SENSING SYSTEMS”, filed on Jul. 12, 2019,   (l) U.S. Provisional Patent application 62/900,565, entitled “QUALIFIED WIRELESS SENSING SYSTEM”, filed on Sep. 15, 2019,   (m) U.S. Provisional Patent application 62/902,357, entitled “METHOD, APPARATUS, AND SYSTEM FOR AUTOMATIC AND OPTIMIZED DEVICE-TO-CLOUD CONNECTION FOR WIRELESS SENSING”, filed on Sep. 18, 2019,   (n) U.S. patent application Ser. No. 16/667,648, entitled “METHOD, APPARATUS, AND SYSTEM FOR WIRELESS PROXIMITY AND PRESENCE MONITORING”, filed on Oct. 29, 2019,   (o) U.S. patent application Ser. No. 16/667,757, entitled “METHOD, APPARATUS, AND SYSTEM FOR HUMAN IDENTIFICATION BASED ON HUMAN RADIO BIOMETRIC INFORMATION”, filed on Oct. 29, 2019,   (p) U.S. Provisional Patent application 62/950,093, entitled “METHOD, APPARATUS, AND SYSTEM FOR TARGET POSITIONING”, filed on Dec. 18, 2019,   (q) U.S. patent application Ser. No. 16/790,610, entitled “METHOD, APPARATUS, AND SYSTEM FOR WIRELESS GAIT RECOGNITION”, filed Feb. 13, 2020,   (r) U.S. patent application Ser. No. 16/790,627, entitled “METHOD, APPARATUS, AND SYSTEM FOR OUTDOOR TARGET TRACKING”, filed Feb. 13, 2020.   (s) U.S. Provisional Patent application 62/977,326, entitled “METHOD, APPARATUS, AND SYSTEM FOR AUTOMATIC AND ADAPTIVE WIRELESS MONITORING AND TRACKING”, filed on Feb. 16, 2020,   (t) U.S. patent application Ser. No. 16/798,337, entitled “METHOD, APPARATUS, AND SYSTEM FOR WIRELESS OBJECT SCANNING”, filed Feb. 22, 2020,   (u) U.S. patent application Ser. No. 16/798,343, entitled “METHOD, APPARATUS, AND SYSTEM FOR WIRELESS OBJECT TRACKING”, filed Feb. 22, 2020,   (v) U.S. Provisional Patent application 62/980,206, entitled “METHOD, APPARATUS, AND SYSTEM FOR WIRELESS SENSING”, filed on Feb. 22, 2020,   (w) U.S. Provisional Patent application 62/981,387, entitled “METHOD, APPARATUS, AND SYSTEM FOR VEHICLE WIRELESS MONITORING”, filed on Feb. 25, 2020,   (x) U.S. Provisional Patent application 62/984,737, entitled “METHOD, APPARATUS, AND SYSTEM FOR IMPROVED WIRELESS MONITORING”, filed on Mar. 3, 2020,   (y) U.S. Provisional Patent application 63/001,226, entitled “METHOD, APPARATUS, AND SYSTEM FOR IMPROVED WIRELESS MONITORING AND USER INTERFACE”, filed on Mar. 27, 2020.       

    
    
     TECHNICAL FIELD 
     The present teaching generally relates wireless artificial intelligent applications. More specifically, the present teaching relates to monitor breathing rate, count number of people, and identify people in a rich-scattering environment. 
     BACKGROUND 
     Human-centric sensing via wireless radio frequency (RF) has attracted an increasing interest for a range of Internet of Things (IoT) applications. Demands of accurate and passive awareness of the environment surge for many applications. For instance, a smart home can adjust the light and ventilation system based on occupancy level to improve energy efficiency. People recognition in smart homes enables user authentication for home security and privacy protection. Besides understanding the environment, monitoring the status of human in the environment also has received great attention, and respiration/breathing rate, serving as a significant vital sign, has been an important topic for RF sensing. 
     Compared with conventional methods that use dedicated sensors to monitor breathing rates, RF sensing provides contact-free solutions. The RF-based solutions can be classified into two categories, i.e., radar-based methods and WiFi-based methods. For radar-based methods, previous works have shown the potential of using millimeter wave (mmWave) or ultra-wideband (UWB) to monitor respiration rate as well as heart rate. Although these systems can achieve high accuracy, dedicated devices hinder their deployment. WiFi-based methods, on the contrary, can be easily deployed and have been studied in the past decade. Received signal strength (RSS) measured by a WiFi device has been used to measure the chest movement during breathing. However, the accuracy of respiration rate estimation degrades when the test subjects do not hold the device. Fine-grained channel state information (CSI) is more sensitive to the environment changes, which has been utilized to capture minute movements caused by respiration. However, due to the omni-directional propagation and narrow bandwidth of commonly used 2.4/5 GHz WiFi, the received signal can be reflected from multiple humans in an indoor space. This makes it difficult to extract the vital signs of multiple humans from the reflected signal. Most of the existing works assume that there is only one person in the observation area or assume the respiration rates of different people are distinct and the number of people is known in advance. 
     SUMMARY 
     The present teaching generally relates wireless artificial intelligent. More specifically, the present teaching relates to monitor breathing rate, count number of people, and identify people in a rich-scattering environment, e.g. an indoor environment or urban metropolitan area, enclosed environment, a car, etc. In one embodiment, the present teaching relates to accurately identify and recognize the driver based on wireless channel information, monitor driver&#39;s and passengers&#39; breathing rate, count number of passengers, and detect presence of unattended children in a rich-scattering environment, e.g. an indoor environment or urban metropolitan area, enclosed environment, a car, etc. 
     In one embodiment, a system for rhythmic motion monitoring is described. The system comprises: a transmitter, a receiver, and a processor. The transmitter is configured for transmitting a wireless signal through a wireless multipath channel that is impacted by a rhythmic motion of an object in a venue. The receiver is configured for: receiving the wireless signal through the wireless multipath channel, and extracting N1 time series of channel information (TSCI) of the wireless multipath channel from the wireless signal modulated by the wireless multipath channel that is impacted by the rhythmic motion of the object, wherein each of the N1 TSCI is associated with an antenna of the transmitter and an antenna of the receiver. The processor is configured for: decomposing each of the N1 TSCI into N2 time series of channel information components (TSCIC), wherein a channel information component (CIC) of each of the N2 TSCIC at a time comprises a respective component of a channel information (CI) of the TSCI at the time, monitoring the rhythmic motion of the object based on at least one of: the N1*N2 TSCIC and the N1 TSCI, wherein N1 and N2 are positive integers, and triggering a response action based on the monitoring of the rhythmic motion of the object. 
     In another embodiment, a method, implemented by a processor, a memory communicatively coupled with the processor, and a set of instructions stored in the memory to be executed by the processor, is described. The method comprises: obtaining N1 time series of channel information (TSCI) of a wireless multipath channel that is impacted by a rhythmic motion of an object in a venue, wherein the N1 TSCI is extracted from a wireless signal transmitted from a transmitter to a receiver through the wireless multipath channel, wherein each of the N1 TSCI is associated with an antenna of the transmitter and an antenna of the receiver; decomposing each of the N1 TSCI into N2 time series of channel information components (TSCIC), wherein a channel information component (CIC) of each of the N2 TSCIC at a time comprises a respective component of a channel information (CI) of the TSCI at the time, wherein N1 and N2 are positive integers; monitoring the rhythmic motion of the object based on at least one of: the N1*N2 TSCIC and the N1 TSCI; and triggering a response action based on the monitoring of the rhythmic motion of the object. 
     In a different embodiment, an apparatus is disclosed for rhythmic motion monitoring in a venue where a transmitter and a receiver are located. The apparatus comprises: at least one of the transmitter and the receiver, and a processor. The transmitter is configured for transmitting a wireless signal through a wireless multipath channel that is impacted by a rhythmic motion of an object in the venue. The receiver is configured for receiving the wireless signal through the wireless multipath channel, and extracting N1 time series of channel information (TSCI) of the wireless multipath channel from the wireless signal modulated by the wireless multipath channel that is impacted by the rhythmic motion of the object. Each of the N1 TSCI is associated with an antenna of the transmitter and an antenna of the receiver. The processor is configured for: decomposing each of the N1 TSCI into N2 time series of channel information components (TSCIC), wherein a channel information component (CIC) of each of the N2 TSCIC at a time comprises a respective component of a channel information (CI) of the TSCI at the time, monitoring the rhythmic motion of the object based on at least one of: the N1*N2 TSCIC and the N1 TSCI, wherein N1 and N2 are positive integers, and triggering a response action based on the monitoring of the rhythmic motion of the object. 
     Other concepts relate to software for implementing the present teaching on wirelessly monitor breathing rate, count number of people, and identify people in a rich-scattering environment. Additional novel features will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following and the accompanying drawings or may be learned by production or operation of the examples. The novel features of the present teachings may be realized and attained by practice or use of various aspects of the methodologies, instrumentalities and combinations set forth in the detailed examples discussed below. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       The methods, systems, and/or devices described herein are further described in terms of exemplary embodiments. These exemplary embodiments are described in detail with reference to the drawings. These embodiments are non-limiting exemplary embodiments, in which like reference numerals represent similar structures throughout the several views of the drawings. 
         FIG. 1  illustrates an exemplary an exemplary processing flow of the system, according to various embodiments of the present teaching. 
         FIG. 2  illustrates an exemplary power spectrum density of the CIR amplitude of 6 links with a scenario that 3 people sit in car with breathing rate [10 14 15] bpm, according to various embodiments of the present teaching. 
         FIG. 3  illustrates an exemplary normalized power spectrum density of different links after subcarrier (SC) combination with a scenario that 3 people sit in car with breathing rate [10 14 15] bpm, according to various embodiments of the present teaching. 
         FIG. 4  illustrates an exemplary power spectrum density after link combination when 3 people sit in car with breathing rate [10 14 15] bpm, according to various embodiments of the present teaching. 
         FIG. 5  illustrates an exemplary spectrum after link combination with a scenario that 3 people sit in car doing natural breathing and their average breathing rate are [10 14 15] bpm, according to various embodiments of the present teaching. 
         FIGS. 6A-6C  illustrate an exemplary procedure of iterative dynamic programming (IDP), according to various embodiments of the present teaching. 
         FIGS. 7A-7D  illustrate exemplary traces found by IDP in four adjacent time windows, according to various embodiments of the present teaching. 
         FIG. 8  illustrates an exemplary trace concatenation result of windows corresponding to  FIGS. 7A-7D , according to various embodiments of the present teaching. 
         FIG. 9  illustrates an exemplary effect of quasi-bilateral filter in people counting, according to various embodiments of the present teaching. 
         FIG. 10  illustrates an exemplary estimated probability density function (PDF) of 4 testing subjects for people recognition, according to various embodiments of the present teaching. 
         FIG. 11A  illustrates an exemplary confusion matrix of a disclosed system for people counting in a lab, according to various embodiments of the present teaching. 
         FIG. 11B  illustrates an exemplary confusion matrix of another system for people counting in a lab, according to various embodiments of the present teaching. 
         FIG. 11C  illustrates an exemplary confusion matrix of a disclosed system without quasi-bilateral filter enabled for people counting in a lab, according to various embodiments of the present teaching. 
         FIG. 12A  illustrates an exemplary confusion matrix of a disclosed system for people counting in a car, according to various embodiments of the present teaching. 
         FIG. 12B  illustrates an exemplary confusion matrix of another system for people counting in a car, according to various embodiments of the present teaching. 
         FIG. 12C  illustrates an exemplary confusion matrix of a disclosed system without quasi-bilateral filter enabled for people counting in a car, according to various embodiments of the present teaching. 
         FIG. 13  illustrates an exemplary confusion matrix of people recognition in a smart home scenario, according to various embodiments of the present teaching. 
         FIG. 14  illustrates an experiment setup for resolution investigation, where 3 users sit at different spatial separations and with different breathing frequency separations, according to various embodiments of the present teaching. 
         FIG. 15  illustrates an exemplary set of experiment results, according to various embodiments of the present teaching. 
         FIG. 16  illustrates an exemplary iterative dynamic programming algorithm, according to various embodiments of the present teaching. 
         FIG. 17  illustrates an exemplary trace concatenating algorithm, according to various embodiments of the present teaching. 
         FIG. 18  illustrates an exemplary day view showing separate instances of sleep, according to some embodiments of the present teaching. 
         FIG. 19A  and  FIG. 19B  illustrate exemplary weekly views showing a 24 hour scale, according to some embodiments of the present teaching. 
         FIG. 20A  and  FIG. 20B  illustrate exemplary home views showing real-time breathing rate and movement index, according to some embodiments of the present teaching. 
         FIGS. 21-27  illustrate more exemplary views of lifelog display, according to some embodiments of the present teaching. 
     
    
    
     DETAILED DESCRIPTION 
     In the following detailed description, numerous specific details are set forth by way of examples in order to provide a thorough understanding of the relevant teachings. However, it should be apparent to those skilled in the art that the present teachings may be practiced without such details. In other instances, well known methods, procedures, components, and/or circuitry have been described at a relatively high-level, without detail, in order to avoid unnecessarily obscuring aspects of the present teachings. 
     In the following detailed description, numerous specific details are set forth by way of examples in order to provide a thorough understanding of the relevant teachings. However, it should be apparent to those skilled in the art that the present teachings may be practiced without such details. In other instances, well known methods, procedures, components, and/or circuitry have been described at a relatively high-level, without detail, in order to avoid unnecessarily obscuring aspects of the present teachings. 
     In one embodiment, the present teaching discloses a method, apparatus, device, system, and/or software (method/apparatus/device/system/software) of a wireless monitoring system. A time series of channel information (CI) of a wireless multipath channel (channel) may be obtained (e.g. dynamically) using a processor, a memory communicatively coupled with the processor and a set of instructions stored in the memory. The time series of CI (TSCI) may be extracted from a wireless signal (signal) transmitted between a Type 1 heterogeneous wireless device (e.g. wireless transmitter, TX) and a Type 2 heterogeneous wireless device (e.g. wireless receiver, RX) in a venue through the channel. The channel may be impacted by an expression (e.g. motion, movement, expression, and/or change in position/pose/shape/expression) of an object in the venue. A characteristics and/or a spatial-temporal information (STI, e.g. motion information) of the object and/or of the motion of the object may be monitored based on the TSCI. A task may be performed based on the characteristics and/or STI. A presentation associated with the task may be generated in a user-interface (UI) on a device of a user. The TSCI may be a wireless signal stream. The TSCI or each CI may be preprocessed. A device may be a station (STA). The symbol “A/B” means “A and/or B” in the present teaching. 
     The expression may comprise placement, placement of moveable parts, location, position, orientation, identifiable place, region, spatial coordinate, presentation, state, static expression, size, length, width, height, angle, scale, shape, curve, surface, area, volume, pose, posture, manifestation, body language, dynamic expression, motion, motion sequence, gesture, extension, contraction, distortion, deformation, body expression (e.g. head, face, eye, mouth, tongue, hair, voice, neck, limbs, arm, hand, leg, foot, muscle, moveable parts), surface expression (e.g. shape, texture, material, color, electromagnetic (EM) characteristics, visual pattern, wetness, reflectance, translucency, flexibility), material property (e.g. living tissue, hair, fabric, metal, wood, leather, plastic, artificial material, solid, liquid, gas, temperature), movement, activity, behavior, change of expression, and/or some combination. 
     The wireless signal may comprise: transmitted/received signal, EM radiation, RF signal/transmission, signal in licensed/unlicensed/ISM band, bandlimited signal, baseband signal, wireless/mobile/cellular communication signal, wireless/mobile/cellular network signal, mesh signal, light signal/communication, downlink/uplink signal, unicast/multicast/broadcast signal, standard (e.g. WLAN, WWAN, WPAN, WBAN, international, national, industry, defacto, IEEE, IEEE 802, 802.11/15/16, WiFi, 802.11n/ac/ax/be, 3G/4G/LTE/5G/6G/7G/8G, 3GPP, Bluetooth, BLE, Zigbee, RFID, UWB, WiMax) compliant signal, protocol signal, standard frame, beacon/pilot/probe/enquiry/acknowledgement/handshake/synchronization signal, management/control/data frame, management/control/data signal, standardized wireless/cellular communication protocol, reference signal, source signal, motion probe/detection/sensing signal, and/or series of signals. The wireless signal may comprise a line-of-sight (LOS), and/or a non-LOS component (or path/link). Each CI may be extracted/generated/computed/sensed at a layer (e.g. PHY/MAC layer in OSI model) of Type 2 device and may be obtained by an application (e.g. software, firmware, driver, app, wireless monitoring software/system). 
     The wireless multipath channel may comprise: a communication channel, analog frequency channel (e.g. with analog carrier frequency near 700/800/900 MHz, 1.8/1.8/2.4/3/5/6/27/60 GHz), coded channel (e.g. in CDMA), and/or channel of a wireless network/system (e.g. WLAN, WiFi, mesh, LTE, 4G/5G, Bluetooth, Zigbee, UWB, RFID, microwave). It may comprise more than one channel. The channels may be consecutive (e.g. with adjacent/overlapping bands) or non-consecutive channels (e.g. non-overlapping WiFi channels, one at 2.4 GHz and one at 5 GHz). 
     The TSCI may be extracted from the wireless signal at a layer of the Type 2 device (e.g. a layer of OSI reference model, physical layer, data link layer, logical link control layer, media access control (MAC) layer, network layer, transport layer, session layer, presentation layer, application layer, TCP/IP layer, internet layer, link layer). The TSCI may be extracted from a derived signal (e.g. baseband signal, motion detection signal, motion sensing signal) derived from the wireless signal (e.g. RF signal). It may be (wireless) measurements sensed by the communication protocol (e.g. standardized protocol) using existing mechanism (e.g. wireless/cellular communication standard/network, 3G/LTE/4G/5G/6G/7G/8G, WiFi, IEEE 802.11/15/16). The derived signal may comprise a packet with at least one of: a preamble, a header and a payload (e.g. for data/control/management in wireless links/networks). The TSCI may be extracted from a probe signal (e.g. training sequence, STF, LTF, L-STF, L-LTF, L-SIG, HE-STF, HE-LTF, HE-SIG-A, HE-SIG-B, CEF) in the packet. A motion detection/sensing signal may be recognized/identified base on the probe signal. The packet may be a standard-compliant protocol frame, management frame, control frame, data frame, sounding frame, excitation frame, illumination frame, null data frame, beacon frame, pilot frame, probe frame, request frame, response frame, association frame, reassociation frame, disassociation frame, authentication frame, action frame, report frame, poll frame, announcement frame, extension frame, enquiry frame, acknowledgement frame, RTS frame, CTS frame, QoS frame, CF-Poll frame, CF-Ack frame, block acknowledgement frame, reference frame, training frame, and/or synchronization frame. 
     The packet may comprise a control data and/or a motion detection probe. A data (e.g. ID/parameters/characteristics/settings/control signal/command/instruction/notification/broadcasting-related information of the Type 1 device) may be obtained from the payload. The wireless signal may be transmitted by the Type 1 device. It may be received by the Type 2 device. A database (e.g. in local server, hub device, cloud server, storage network) may be used to store the TSCI, characteristics, STI, signatures, patterns, behaviors, trends, parameters, analytics, output responses, identification information, user information, device information, channel information, venue (e.g. map, environmental model, network, proximity devices/networks) information, task information, class/category information, presentation (e.g. UI) information, and/or other information. 
     The Type 1/Type 2 device may comprise at least one of: electronics, circuitry, transmitter (TX)/receiver (RX)/transceiver, RF interface, “Origin Satellite”/“Tracker Bot”, unicast/multicast/broadcasting device, wireless source device, source/destination device, wireless node, hub device, target device, motion detection device, sensor device, remote/wireless sensor device, wireless communication device, wireless-enabled device, standard compliant device, and/or receiver. The Type 1 (or Type 2) device may be heterogeneous because, when there are more than one instances of Type 1 (or Type 2) device, they may have different circuitry, enclosure, structure, purpose, auxiliary functionality, chip/IC, processor, memory, software, firmware, network connectivity, antenna, brand, model, appearance, form, shape, color, material, and/or specification. The Type 1/Type 2 device may comprise: access point, router, mesh router, internet-of-things (IoT) device, wireless terminal, one or more radio/RF subsystem/wireless interface (e.g. 2.4 GHz radio, 5 GHz radio, front haul radio, backhaul radio), modem, RF front end, RF/radio chip or integrated circuit (IC). 
     At least one of: Type 1 device, Type 2 device, a link between them, the object, the characteristics, the STI, the monitoring of the motion, and the task may be associated with an identification (ID) such as UUID. The Type 1/Type 2/another device may obtain/store/retrieve/access/preprocess/condition/process/analyze/monitor/apply the TSCI. The Type 1 and Type 2 devices may communicate network traffic in another channel (e.g. Ethernet, HDMI, USB, Bluetooth, BLE, WiFi, LTE, other network, the wireless multipath channel) in parallel to the wireless signal. The Type 2 device may passively observe/monitor/receive the wireless signal from the Type 1 device in the wireless multipath channel without establishing connection (e.g. association/authentication) with, or requesting service from, the Type 1 device. 
     The transmitter (i.e. Type 1 device) may function as (play role of) receiver (i.e. Type 2 device) temporarily, sporadically, continuously, repeatedly, interchangeably, alternately, simultaneously, concurrently, and/or contemporaneously; and vice versa. A device may function as Type 1 device (transmitter) and/or Type 2 device (receiver) temporarily, sporadically, continuously, repeatedly, simultaneously, concurrently, and/or contemporaneously. There may be multiple wireless nodes each being Type 1 (TX) and/or Type 2 (RX) device. A TSCI may be obtained between every two nodes when they exchange/communicate wireless signals. The characteristics and/or STI of the object may be monitored individually based on a TSCI, or jointly based on two or more (e.g. all) TSCI. The motion of the object may be monitored actively (in that Type 1 device, Type 2 device, or both, are wearable of/associated with the object) and/or passively (in that both Type 1 and Type 2 devices are not wearable of/associated with the object). It may be passive because the object may not be associated with the Type 1 device and/or the Type 2 device. The object (e.g. user, an automated guided vehicle or AGV) may not need to carry/install any wearables/fixtures (i.e. the Type 1 device and the Type 2 device are not wearable/attached devices that the object needs to carry in order perform the task). It may be active because the object may be associated with either the Type 1 device and/or the Type 2 device. The object may carry (or installed) a wearable/a fixture (e.g. the Type 1 device, the Type 2 device, a device communicatively coupled with either the Type 1 device or the Type 2 device). 
     The presentation may be visual, audio, image, video, animation, graphical presentation, text, etc. A computation of the task may be performed by a processor (or logic unit) of the Type 1 device, a processor (or logic unit) of an IC of the Type 1 device, a processor (or logic unit) of the Type 2 device, a processor of an IC of the Type 2 device, a local server, a cloud server, a data analysis subsystem, a signal analysis subsystem, and/or another processor. The task may be performed with/without reference to a wireless fingerprint or a baseline (e.g. collected, processed, computed, transmitted and/or stored in a training phase/survey/current survey/previous survey/recent survey/initial wireless survey, a passive fingerprint), a training, a profile, a trained profile, a static profile, a survey, an initial wireless survey, an initial setup, an installation, a re-training, an updating and a reset. 
     The Type 1 device (TX device) may comprise at least one heterogeneous wireless transmitter. The Type 2 device (RX device) may comprise at least one heterogeneous wireless receiver. The Type 1 device and the Type 2 device may be collocated. The Type 1 device and the Type 2 device may be the same device. Any device may have a data processing unit/apparatus, a computing unit/system, a network unit/system, a processor (e.g. logic unit), a memory communicatively coupled with the processor, and a set of instructions stored in the memory to be executed by the processor. Some processors, memories and sets of instructions may be coordinated. There may be multiple Type 1 devices interacting (e.g. communicating, exchange signal/control/notification/other data) with the same Type 2 device (or multiple Type 2 devices), and/or there may be multiple Type 2 devices interacting with the same Type 1 device. The multiple Type 1 devices/Type 2 devices may be synchronized and/or asynchronous, with same/different window width/size and/or time shift, same/different synchronized start time, synchronized end time, etc. Wireless signals sent by the multiple Type 1 devices may be sporadic, temporary, continuous, repeated, synchronous, simultaneous, concurrent, and/or contemporaneous. The multiple Type 1 devices/Type 2 devices may operate independently and/or collaboratively. A Type 1 and/or Type 2 device may have/comprise/be heterogeneous hardware circuitry (e.g. a heterogeneous chip or a heterogeneous IC capable of generating/receiving the wireless signal, extracting CI from received signal, or making the CI available). They may be communicatively coupled to same or different servers (e.g. cloud server, edge server, local server, hub device). 
     Operation of one device may be based on operation, state, internal state, storage, processor, memory output, physical location, computing resources, network of another device. Difference devices may communicate directly, and/or via another device/server/hub device/cloud server. The devices may be associated with one or more users, with associated settings. The settings may be chosen once, pre-programmed, and/or changed (e.g. adjusted, varied, modified)/varied over time. There may be additional steps in the method. The steps and/or the additional steps of the method may be performed in the order shown or in another order. Any steps may be performed in parallel, iterated, or otherwise repeated or performed in another manner. A user may be human, adult, older adult, man, woman, juvenile, child, baby, pet, animal, creature, machine, computer module/software, etc. 
     In the case of one or multiple Type 1 devices interacting with one or multiple Type 2 devices, any processing (e.g. time domain, frequency domain) may be different for different devices. The processing may be based on locations, orientation, direction, roles, user-related characteristics, settings, configurations, available resources, available bandwidth, network connection, hardware, software, processor, co-processor, memory, battery life, available power, antennas, antenna types, directional/unidirectional characteristics of the antenna, power setting, and/or other parameters/characteristics of the devices. 
     The wireless receiver (e.g. Type 2 device) may receive the signal and/or another signal from the wireless transmitter (e.g. Type 1 device). The wireless receiver may receive another signal from another wireless transmitter (e.g. a second Type 1 device). The wireless transmitter may transmit the signal and/or another signal to another wireless receiver (e.g. a second Type 2 device). The wireless transmitter, wireless receiver, another wireless receiver and/or another wireless transmitter may be moving with the object and/or another object. The another object may be tracked. 
     The Type 1 and/or Type 2 device may be capable of wirelessly coupling with at least two Type 2 and/or Type 1 devices. The Type 1 device may be caused/controlled to switch/establish wireless coupling (e.g. association, authentication) from the Type 2 device to a second Type 2 device at another location in the venue. Similarly, the Type 2 device may be caused/controlled to switch/establish wireless coupling from the Type 1 device to a second Type 1 device at yet another location in the venue. The switching may be controlled by a server (or a hub device), the processor, the Type 1 device, the Type 2 device, and/or another device. The radio used before and after switching may be different. A second wireless signal (second signal) may be caused to be transmitted between the Type 1 device and the second Type 2 device (or between the Type 2 device and the second Type 1 device) through the channel. A second TSCI of the channel extracted from the second signal may be obtained. The second signal may be the first signal. The characteristics, STI and/or another quantity of the object may be monitored based on the second TSCI. The Type 1 device and the Type 2 device may be the same. The characteristics, STI and/or another quantity with different time stamps may form a waveform. The waveform may be displayed in the presentation. 
     The wireless signal and/or another signal may have data embedded. The wireless signal may be a series of probe signals (e.g. a repeated transmission of probe signals, a re-use of one or more probe signals). The probe signals may change/vary over time. A probe signal may be a standard compliant signal, protocol signal, standardized wireless protocol signal, control signal, data signal, wireless communication network signal, cellular network signal, WiFi signal, LTE/5G/6G/7G signal, reference signal, beacon signal, motion detection signal, and/or motion sensing signal. A probe signal may be formatted according to a wireless network standard (e.g. WiFi), a cellular network standard (e.g. LTE/5G/6G), or another standard. A probe signal may comprise a packet with a header and a payload. A probe signal may have data embedded. The payload may comprise data. A probe signal may be replaced by a data signal. The probe signal may be embedded in a data signal. The wireless receiver, wireless transmitter, another wireless receiver and/or another wireless transmitter may be associated with at least one processor, memory communicatively coupled with respective processor, and/or respective set of instructions stored in the memory which when executed cause the processor to perform any and/or all steps needed to determine the STI (e.g. motion information), initial STI, initial time, direction, instantaneous location, instantaneous angle, and/or speed, of the object. The processor, the memory and/or the set of instructions may be associated with the Type 1 device, one of the at least one Type 2 device, the object, a device associated with the object, another device associated with the venue, a cloud server, a hub device, and/or another server. 
     The Type 1 device may transmit the signal in a broadcasting manner to at least one Type 2 device(s) through the channel in the venue. The signal is transmitted without the Type 1 device establishing wireless connection (e.g. association, authentication) with any Type 2 device, and without any Type 2 device requesting services from the Type 1 device. The Type 1 device may transmit to a particular media access control (MAC) address common for more than one Type 2 devices. Each Type 2 device may adjust its MAC address to the particular MAC address. The particular MAC address may be associated with the venue. The association may be recorded in an association table of an Association Server (e.g. hub device). The venue may be identified by the Type 1 device, a Type 2 device and/or another device based on the particular MAC address, the series of probe signals, and/or the at least one TSCI extracted from the probe signals. For example, a Type 2 device may be moved to a new location in the venue (e.g. from another venue). The Type 1 device may be newly set up in the venue such that the Type 1 and Type 2 devices are not aware of each other. During set up, the Type 1 device may be instructed/guided/caused/controlled (e.g. using dummy receiver, using hardware pin setting/connection, using stored setting, using local setting, using remote setting, using downloaded setting, using hub device, or using server) to send the series of probe signals to the particular MAC address. Upon power up, the Type 2 device may scan for probe signals according to a table of MAC addresses (e.g. stored in a designated source, server, hub device, cloud server) that may be used for broadcasting at different locations (e.g. different MAC address used for different venue such as house, office, enclosure, floor, multi-storey building, store, airport, mall, stadium, hall, station, subway, lot, area, zone, region, district, city, country, continent). When the Type 2 device detects the probe signals sent to the particular MAC address, the Type 2 device can use the table to identify the venue based on the MAC address. A location of a Type 2 device in the venue may be computed based on the particular MAC address, the series of probe signals, and/or the at least one TSCI obtained by the Type 2 device from the probe signals. The computing may be performed by the Type 2 device. The particular MAC address may be changed (e.g. adjusted, varied, modified) over time. It may be changed according to a time table, rule, policy, mode, condition, situation and/or change. The particular MAC address may be selected based on availability of the MAC address, a pre-selected list, collision pattern, traffic pattern, data traffic between the Type 1 device and another device, effective bandwidth, random selection, and/or a MAC address switching plan. The particular MAC address may be the MAC address of a second wireless device (e.g. a dummy receiver, or a receiver that serves as a dummy receiver). 
     The Type 1 device may transmit the probe signals in a channel selected from a set of channels. At least one CI of the selected channel may be obtained by a respective Type 2 device from the probe signal transmitted in the selected channel. The selected channel may be changed (e.g. adjusted, varied, modified) over time. The change may be according to a time table, rule, policy, mode, condition, situation, and/or change. The selected channel may be selected based on availability of channels, random selection, a pre-selected list, co-channel interference, inter-channel interference, channel traffic pattern, data traffic between the Type 1 device and another device, effective bandwidth associated with channels, security criterion, channel switching plan, a criterion, a quality criterion, a signal quality condition, and/or consideration. 
     The particular MAC address and/or an information of the selected channel may be communicated between the Type 1 device and a server (e.g. hub device) through a network. The particular MAC address and/or the information of the selected channel may also be communicated between a Type 2 device and a server (e.g. hub device) through another network. The Type 2 device may communicate the particular MAC address and/or the information of the selected channel to another Type 2 device (e.g. via mesh network, Bluetooth, WiFi, NFC, ZigBee, etc.). The particular MAC address and/or selected channel may be chosen by a server (e.g. hub device). The particular MAC address and/or selected channel may be signaled in an announcement channel by the Type 1 device, the Type 2 device and/or a server (e.g. hub device). Before being communicated, any information may be pre-processed. 
     Wireless connection (e.g. association, authentication) between the Type 1 device and another wireless device may be established (e.g. using a signal handshake). The Type 1 device may send a first handshake signal (e.g. sounding frame, probe signal, request-to-send RTS) to the another device. The another device may reply by sending a second handshake signal (e.g. a command, or a clear-to-send CTS) to the Type 1 device, triggering the Type 1 device to transmit the signal (e.g. series of probe signals) in the broadcasting manner to multiple Type 2 devices without establishing connection with any Type 2 device. The second handshake signals may be a response or an acknowledge (e.g. ACK) to the first handshake signal. The second handshake signal may contain a data with information of the venue, and/or the Type 1 device. The another device may be a dummy device with a purpose (e.g. primary purpose, secondary purpose) to establish the wireless connection with the Type 1 device, to receive the first signal, and/or to send the second signal. The another device may be physically attached to the Type 1 device. 
     In another example, the another device may send a third handshake signal to the Type 1 device triggering the Type 1 device to broadcast the signal (e.g. series of probe signals) to multiple Type 2 devices without establishing connection (e.g. association, authentication) with any Type 2 device. The Type 1 device may reply to the third special signal by transmitting a fourth handshake signal to the another device. The another device may be used to trigger more than one Type 1 devices to broadcast. The triggering may be sequential, partially sequential, partially parallel, or fully parallel. The another device may have more than one wireless circuitries to trigger multiple transmitters in parallel. Parallel trigger may also be achieved using at least one yet another device to perform the triggering (similar to what as the another device does) in parallel to the another device. The another device may not communicate (or suspend communication) with the Type 1 device after establishing connection with the Type 1 device. Suspended communication may be resumed. The another device may enter an inactive mode, hibernation mode, sleep mode, stand-by mode, low-power mode, OFF mode and/or power-down mode, after establishing the connection with the Type 1 device. The another device may have the particular MAC address so that the Type 1 device sends the signal to the particular MAC address. The Type 1 device and/or the another device may be controlled and/or coordinated by a first processor associated with the Type 1 device, a second processor associated with the another device, a third processor associated with a designated source and/or a fourth processor associated with another device. The first and second processors may coordinate with each other. 
     A first series of probe signals may be transmitted by a first antenna of the Type 1 device to at least one first Type 2 device through a first channel in a first venue. A second series of probe signals may be transmitted by a second antenna of the Type 1 device to at least one second Type 2 device through a second channel in a second venue. The first series and the second series may/may not be different. The at least one first Type 2 device may/may not be different from the at least one second Type 2 device. The first and/or second series of probe signals may be broadcasted without connection (e.g. association, authentication) established between the Type 1 device and any Type 2 device. The first and second antennas may be same/different. The two venues may have different sizes, shape, multipath characteristics. The first and second venues may overlap. The respective immediate areas around the first and second antennas may overlap. The first and second channels may be same/different. For example, the first one may be WiFi while the second may be LTE. Or, both may be WiFi, but the first one may be 2.4 GHz WiFi and the second may be 5 GHz WiFi. Or, both may be 2.4 GHz WiFi, but have different channel numbers, SSID names, and/or WiFi settings. 
     Each Type 2 device may obtain at least one TSCI from the respective series of probe signals, the CI being of the respective channel between the Type 2 device and the Type 1 device. Some first Type 2 device(s) and some second Type 2 device(s) may be the same. The first and second series of probe signals may be synchronous/asynchronous. A probe signal may be transmitted with data or replaced by a data signal. The first and second antennas may be the same. The first series of probe signals may be transmitted at a first rate (e.g. 30 Hz). The second series of probe signals may be transmitted at a second rate (e.g. 200 Hz). The first and second rates may be same/different. The first and/or second rate may be changed (e.g. adjusted, varied, modified) over time. The change may be according to a time table, rule, policy, mode, condition, situation, and/or change. Any rate may be changed (e.g. adjusted, varied, modified) over time. The first and/or second series of probe signals may be transmitted to a first MAC address and/or second MAC address respectively. The two MAC addresses may be same/different. The first series of probe signals may be transmitted in a first channel. The second series of probe signals may be transmitted in a second channel. The two channels may be same/different. The first or second MAC address, first or second channel may be changed over time. Any change may be according to a time table, rule, policy, mode, condition, situation, and/or change. 
     The Type 1 device and another device may be controlled and/or coordinated, physically attached, or may be of/in/of a common device. They may be controlled by/connected to a common data processor, or may be connected to a common bus interconnect/network/LAN/Bluetooth network/NFC network/BLE network/wired network/wireless network/mesh network/mobile network/cloud. They may share a common memory, or be associated with a common user, user device, profile, account, identity (ID), identifier, household, house, physical address, location, geographic coordinate, IP subnet, SSID, home device, office device, and/or manufacturing device. Each Type 1 device may be a signal source of a set of respective Type 2 devices (i.e. it sends a respective signal (e.g. respective series of probe signals) to the set of respective Type 2 devices). Each respective Type 2 device chooses the Type 1 device from among all Type 1 devices as its signal source. Each Type 2 device may choose asynchronously. At least one TSCI may be obtained by each respective Type 2 device from the respective series of probe signals from the Type 1 device, the CI being of the channel between the Type 2 device and the Type 1 device. The respective Type 2 device chooses the Type 1 device from among all Type 1 devices as its signal source based on identity (ID) or identifier of Type 1/Type 2 device, task to be performed, past signal source, history (e.g. of past signal source, Type 1 device, another Type 1 device, respective Type 2 receiver, and/or another Type 2 receiver), threshold for switching signal source, and/or information of a user, account, access info, parameter, characteristics, and/or signal strength (e.g. associated with the Type 1 device and/or the respective Type 2 receiver). Initially, the Type 1 device may be signal source of a set of initial respective Type 2 devices (i.e. the Type 1 device sends a respective signal (series of probe signals) to the set of initial respective Type 2 devices) at an initial time. Each initial respective Type 2 device chooses the Type 1 device from among all Type 1 devices as its signal source. 
     The signal source (Type 1 device) of a particular Type 2 device may be changed (e.g. adjusted, varied, modified) when (1) time interval between two adjacent probe signals (e.g. between current probe signal and immediate past probe signal, or between next probe signal and current probe signal) received from current signal source of the Type 2 device exceeds a first threshold; (2) signal strength associated with current signal source of the Type 2 device is below a second threshold; (3) a processed signal strength associated with current signal source of the Type 2 device is below a third threshold, the signal strength processed with low pass filter, band pass filter, median filter, moving average filter, weighted averaging filter, linear filter and/or non-linear filter; and/or (4) signal strength (or processed signal strength) associated with current signal source of the Type 2 device is below a fourth threshold for a significant percentage of a recent time window (e.g. 70%, 80%, 90%). The percentage may exceed a fifth threshold. The first, second, third, fourth and/or fifth thresholds may be time varying. 
     Condition (1) may occur when the Type 1 device and the Type 2 device become progressively far away from each other, such that some probe signal from the Type 1 device becomes too weak and is not received by the Type 2 device. Conditions (2)-(4) may occur when the two devices become far from each other such that the signal strength becomes very weak. 
     The signal source of the Type 2 device may not change if other Type 1 devices have signal strength weaker than a factor (e.g. 1, 1.1, 1.2, or 1.5) of the current signal source. If the signal source is changed (e.g. adjusted, varied, modified), the new signal source may take effect at a near future time (e.g. the respective next time). The new signal source may be the Type 1 device with strongest signal strength, and/or processed signal strength. The current and new signal source may be same/different. 
     A list of available Type 1 devices may be initialized and maintained by each Type 2 device. The list may be updated by examining signal strength and/or processed signal strength associated with the respective set of Type 1 devices. A Type 2 device may choose between a first series of probe signals from a first Type 1 device and a second series of probe signals from a second Type 1 device based on: respective probe signal rate, MAC addresses, channels, characteristics/properties/states, task to be performed by the Type 2 device, signal strength of first and second series, and/or another consideration. 
     The series of probe signals may be transmitted at a regular rate (e.g. 100 Hz). The series of probe signals may be scheduled at a regular interval (e.g. 0.01 s for 100 Hz), but each probe signal may experience small time perturbation, perhaps due to timing requirement, timing control, network control, handshaking, message passing, collision avoidance, carrier sensing, congestion, availability of resources, and/or another consideration. The rate may be changed (e.g. adjusted, varied, modified). The change may be according to a time table (e.g. changed once every hour), rule, policy, mode, condition and/or change (e.g. changed whenever some event occur). For example, the rate may normally be 100 Hz, but changed to 1000 Hz in demanding situations, and to 1 Hz in low power/standby situation. The probe signals may be sent in burst. 
     The probe signal rate may change based on a task performed by the Type 1 device or Type 2 device (e.g. a task may need 100 Hz normally and 1000 Hz momentarily for 20 seconds). In one example, the transmitters (Type 1 devices), receivers (Type 2 device), and associated tasks may be associated adaptively (and/or dynamically) to classes (e.g. classes that are: low-priority, high-priority, emergency, critical, regular, privileged, non-subscription, subscription, paying, and/or non-paying). A rate (of a transmitter) may be adjusted for the sake of some class (e.g. high priority class). When the need of that class changes, the rate may be changed (e.g. adjusted, varied, modified). When a receiver has critically low power, the rate may be reduced to reduce power consumption of the receiver to respond to the probe signals. In one example, probe signals may be used to transfer power wirelessly to a receiver (Type 2 device), and the rate may be adjusted to control the amount of power transferred to the receiver. 
     The rate may be changed by (or based on): a server (e.g. hub device), the Type 1 device and/or the Type 2 device. Control signals may be communicated between them. The server may monitor, track, forecast and/or anticipate the needs of the Type 2 device and/or the tasks performed by the Type 2 device, and may control the Type 1 device to change the rate. The server may make scheduled changes to the rate according to a time table. The server may detect an emergency situation and change the rate immediately. The server may detect a developing condition and adjust the rate gradually. The characteristics and/or STI (e.g. motion information) may be monitored individually based on a TSCI associated with a particular Type 1 device and a particular Type 2 device, and/or monitored jointly based on any TSCI associated with the particular Type 1 device and any Type 2 device, and/or monitored jointly based on any TSCI associated with the particular Type 2 device and any Type 1 device, and/or monitored globally based on any TSCI associated with any Type 1 device and any Type 2 device. Any joint monitoring may be associated with: a user, user account, profile, household, map of venue, environmental model of the venue, and/or user history, etc. 
     A first channel between a Type 1 device and a Type 2 device may be different from a second channel between another Type 1 device and another Type 2 device. The two channels may be associated with different frequency bands, bandwidth, carrier frequency, modulation, wireless standards, coding, encryption, payload characteristics, networks, network ID, SSID, network characteristics, network settings, and/or network parameters, etc. The two channels may be associated with different kinds of wireless system (e.g. two of the following: WiFi, LTE, LTE-A, LTE-U, 2.5G, 3G, 3.5G, 4G, beyond 4G, 5G, 6G, 7G, a cellular network standard, UMTS, 3GPP, GSM, EDGE, TDMA, FDMA, CDMA, WCDMA, TD-SCDMA, 802.11 system, 802.15 system, 802.16 system, mesh network, Zigbee, NFC, WiMax, Bluetooth, BLE, RFID, UWB, microwave system, radar like system). For example, one is WiFi and the other is LTE. The two channels may be associated with similar kinds of wireless system, but in different network. For example, the first channel may be associated with a WiFi network named “Pizza and Pizza” in the 2.4 GHz band with a bandwidth of 20 MHz while the second may be associated with a WiFi network with SSID of “StarBud hotspot” in the 5 GHz band with a bandwidth of 40 MHz. The two channels may be different channels in same network (e.g. the “StarBud hotspot” network). 
     In one embodiment, a wireless monitoring system may comprise training a classifier of multiple events in a venue based on training TSCI associated with the multiple events. A CI or TSCI associated with an event may be considered/may comprise a wireless sample/characteristics/fingerprint associated with the event (and/or the venue, the environment, the object, the motion of the object, a state/emotional state/mental state/condition/stage/gesture/gait/action/movement/activity/daily activity/history/event of the object, etc.). For each of the multiple known events happening in the venue in a respective training (e.g. surveying, wireless survey, initial wireless survey) time period associated with the known event, a respective training wireless signal (e.g. a respective series of training probe signals) may be transmitted by an antenna of a first Type 1 heterogeneous wireless device using a processor, a memory and a set of instructions of the first Type 1 device to at least one first Type 2 heterogeneous wireless device through a wireless multipath channel in the venue in the respective training time period. 
     At least one respective time series of training CI (training TSCI) may be obtained asynchronously by each of the at least one first Type 2 device from the (respective) training signal. The CI may be CI of the channel between the first Type 2 device and the first Type 1 device in the training time period associated with the known event. The at least one training TSCI may be preprocessed. The training may be a wireless survey (e.g. during installation of Type 1 device and/or Type 2 device). 
     For a current event happening in the venue in a current time period, a current wireless signal (e.g. a series of current probe signals) may be transmitted by an antenna of a second Type 1 heterogeneous wireless device using a processor, a memory and a set of instructions of the second Type 1 device to at least one second Type 2 heterogeneous wireless device through the channel in the venue in the current time period associated with the current event. At least one time series of current CI (current TSCI) may be obtained asynchronously by each of the at least one second Type 2 device from the current signal (e.g. the series of current probe signals). The CI may be CI of the channel between the second Type 2 device and the second Type 1 device in the current time period associated with the current event. The at least one current TSCI may be preprocessed. 
     The classifier may be applied to classify at least one current TSCI obtained from the series of current probe signals by the at least one second Type 2 device, to classify at least one portion of a particular current TSCI, and/or to classify a combination of the at least one portion of the particular current TSCI and another portion of another TSCI. The classifier may partition TSCI (or the characteristics/STI or other analytics or output responses) into clusters and associate the clusters to specific events/objects/subjects/locations/movements/activities. Labels/tags may be generated for the clusters. The clusters may be stored and retrieved. The classifier may be applied to associate the current TSCI (or characteristics/STI or the other analytics/output response, perhaps associated with a current event) with: a cluster, a known/specific event, a class/category/group/grouping/list/cluster/set of known events/subjects/locations/movements/activities, an unknown event, a class/category/group/grouping/list/cluster/set of unknown events/subjects/locations/movements/activities, and/or another event/subject/location/movement/activity/class/category/group/grouping/list/cluster/set. Each TSCI may comprise at least one CI each associated with a respective timestamp. Two TSCI associated with two Type 2 devices may be different with different: starting time, duration, stopping time, amount of CI, sampling frequency, sampling period. Their CI may have different features. The first and second Type 1 devices may be at same location in the venue. They may be the same device. The at least one second Type 2 device (or their locations) may be a permutation of the at least one first Type 2 device (or their locations). A particular second Type 2 device and a particular first Type 2 device may be the same device. A subset of the first Type 2 device and a subset of the second Type 2 device may be the same. The at least one second Type 2 device and/or a subset of the at least one second Type 2 device may be a subset of the at least one first Type 2 device. The at least one first Type 2 device and/or a subset of the at least one first Type 2 device may be a permutation of a subset of the at least one second Type 2 device. The at least one second Type 2 device and/or a subset of the at least one second Type 2 device may be a permutation of a subset of the at least one first Type 2 device. The at least one second Type 2 device and/or a subset of the at least one second Type 2 device may be at same respective location as a subset of the at least one first Type 2 device. The at least one first Type 2 device and/or a subset of the at least one first Type 2 device may be at same respective location as a subset of the at least one second Type 2 device. 
     The antenna of the Type 1 device and the antenna of the second Type 1 device may be at same location in the venue. Antenna(s) of the at least one second Type 2 device and/or antenna(s) of a subset of the at least one second Type 2 device may be at same respective location as respective antenna(s) of a subset of the at least one first Type 2 device. Antenna(s) of the at least one first Type 2 device and/or antenna(s) of a subset of the at least one first Type 2 device may be at same respective location(s) as respective antenna(s) of a subset of the at least one second Type 2 device. 
     A first section of a first time duration of the first TSCI and a second section of a second time duration of the second section of the second TSCI may be aligned. A map between items of the first section and items of the second section may be computed. The first section may comprise a first segment (e.g. subset) of the first TSCI with a first starting/ending time, and/or another segment (e.g. subset) of a processed first TSCI. The processed first TSCI may be the first TSCI processed by a first operation. The second section may comprise a second segment (e.g. subset) of the second TSCI with a second starting time and a second ending time, and another segment (e.g. subset) of a processed second TSCI. The processed second TSCI may be the second TSCI processed by a second operation. The first operation and/or the second operation may comprise: subsampling, re-sampling, interpolation, filtering, transformation, feature extraction, pre-processing, and/or another operation. 
     A first item of the first section may be mapped to a second item of the second section. The first item of the first section may also be mapped to another item of the second section. Another item of the first section may also be mapped to the second item of the second section. The mapping may be one-to-one, one-to-many, many-to-one, many-to-many. At least one function of at least one of: the first item of the first section of the first TSCI, another item of the first TSCI, timestamp of the first item, time difference of the first item, time differential of the first item, neighboring timestamp of the first item, another timestamp associated with the first item, the second item of the second section of the second TSCI, another item of the second TSCI, timestamp of the second item, time difference of the second item, time differential of the second item, neighboring timestamp of the second item, and another timestamp associated with the second item, may satisfy at least one constraint. 
     One constraint may be that a difference between the timestamp of the first item and the timestamp of the second item may be upper-bounded by an adaptive (and/or dynamically adjusted) upper threshold and lower-bounded by an adaptive lower threshold. 
     The first section may be the entire first TSCI. The second section may be the entire second TSCI. The first time duration may be equal to the second time duration. A section of a time duration of a TSCI may be determined adaptively (and/or dynamically). A tentative section of the TSCI may be computed. A starting time and an ending time of a section (e.g. the tentative section, the section) may be determined. The section may be determined by removing a beginning portion and an ending portion of the tentative section. A beginning portion of a tentative section may be determined as follows. Iteratively, items of the tentative section with increasing timestamp may be considered as a current item, one item at a time. 
     In each iteration, at least one activity measure/index may be computed and/or considered. The at least one activity measure may be associated with at least one of: the current item associated with a current timestamp, past items of the tentative section with timestamps not larger than the current timestamp, and/or future items of the tentative section with timestamps not smaller than the current timestamp. The current item may be added to the beginning portion of the tentative section if at least one criterion (e.g. quality criterion, signal quality condition) associated with the at least one activity measure is satisfied. 
     The at least one criterion associated with the activity measure may comprise at least one of: (a) the activity measure is smaller than an adaptive (e.g. dynamically adjusted) upper threshold, (b) the activity measure is larger than an adaptive lower threshold, (c) the activity measure is smaller than an adaptive upper threshold consecutively for at least a predetermined amount of consecutive timestamps, (d) the activity measure is larger than an adaptive lower threshold consecutively for at least another predetermined amount of consecutive timestamps, (e) the activity measure is smaller than an adaptive upper threshold consecutively for at least a predetermined percentage of the predetermined amount of consecutive timestamps, (f) the activity measure is larger than an adaptive lower threshold consecutively for at least another predetermined percentage of the another predetermined amount of consecutive timestamps, (g) another activity measure associated with another timestamp associated with the current timestamp is smaller than another adaptive upper threshold and larger than another adaptive lower threshold, (h) at least one activity measure associated with at least one respective timestamp associated with the current timestamp is smaller than respective upper threshold and larger than respective lower threshold, (i) percentage of timestamps with associated activity measure smaller than respective upper threshold and larger than respective lower threshold in a set of timestamps associated with the current timestamp exceeds a threshold, and (j) another criterion (e.g. a quality criterion, signal quality condition). 
     An activity measure/index associated with an item at time T1 may comprise at least one of: (1) a first function of the item at time T1 and an item at time T1−D1, wherein D1 is a pre-determined positive quantity (e.g. a constant time offset), (2) a second function of the item at time T1 and an item at time T1+D1, (3) a third function of the item at time T1 and an item at time T2, wherein T2 is a pre-determined quantity (e.g. a fixed initial reference time; T2 may be changed (e.g. adjusted, varied, modified) over time; T2 may be updated periodically; T2 may be the beginning of a time period and T1 may be a sliding time in the time period), and (4) a fourth function of the item at time T1 and another item. 
     At least one of: the first function, the second function, the third function, and/or the fourth function may be a function (e.g. F(X, Y, . . . )) with at least two arguments: X and Y. The two arguments may be scalars. The function (e.g. F) may be a function of at least one of: X, Y, (X−Y), (Y−X), abs(X−Y), X{circumflex over ( )}a, Y{circumflex over ( )}b, abs(X{circumflex over ( )}a−Y{circumflex over ( )}b), (X−Y){circumflex over ( )}a, (X/Y), (X+a)/(Y+b), (X{circumflex over ( )}a/Y{circumflex over ( )}b), and ((X/Y){circumflex over ( )}a−b), wherein a and b are may be some predetermined quantities. For example, the function may simply be abs(X−Y), or (X−Y){circumflex over ( )}2, (X−Y){circumflex over ( )}4. The function may be a robust function. For example, the function may be (X−Y){circumflex over ( )}2 when abs(X−Y) is less than a threshold T, and (X−Y)+a when abs(X−Y) is larger than T. Alternatively, the function may be a constant when abs(X−Y) is larger than T. The function may also be bounded by a slowly increasing function when abs(X−y) is larger than T, so that outliers cannot severely affect the result. Another example of the function may be (abs(X/Y)−a), where a=1. In this way, if X=Y (i.e. no change or no activity), the function will give a value of 0. If X is larger than Y, (X/Y) will be larger than 1 (assuming X and Y are positive) and the function will be positive. And if X is less than Y, (X/Y) will be smaller than 1 and the function will be negative. In another example, both arguments X and Y may be n-tuples such that X=(x_1, x_2, . . . , x_n) and Y=(y_1, y_2, . . . , y_n). The function may be a function of at least one of: x_i, y_i, (x_i−y_i), (y_i−x_i), abs(x_i−y_i), x_i{circumflex over ( )}a, y_i{circumflex over ( )}b, abs(x_i{circumflex over ( )}a−y_i{circumflex over ( )}b), (x_i−y_i){circumflex over ( )}a, (x_i/y_i), (x_i+a)/(y_i+b), (x_i{circumflex over ( )}a/y_i{circumflex over ( )}b), and ((x_i/y_i){circumflex over ( )}a−b), wherein i is a component index of the n-tuple X and Y, and 1&lt;=i&lt;=n. E.g. component index of x_1 is i=1, component index of x_2 is i=2. The function may comprise a component-by-component summation of another function of at least one of the following: x_i, y_i, (x_i−y_i), (y_i−x_i), abs(x_i−y_i), x_i{circumflex over ( )}a, y_i{circumflex over ( )}b, abs(x_i{circumflex over ( )}a−y_i{circumflex over ( )}b), (x_i−y_i){circumflex over ( )}a, (x_i/y_i), (x_i+a)/(y_i+b), (x_i{circumflex over ( )}a/y_i{circumflex over ( )}b), and ((x_i/y_i){circumflex over ( )}a−b), wherein i is the component index of the n-tuple X and Y. For example, the function may be in a form of sum_{i=1}{circumflex over ( )}n(abs(x_i/y_i)−1)/n, or sum_{i=1}{circumflex over ( )}n w_i*(abs(x_i/y_i)−1), where w_i is some weight for component i. 
     The map may be computed using dynamic time warping (DTW). The DTW may comprise a constraint on at least one of: the map, the items of the first TSCI, the items of the second TSCI, the first time duration, the second time duration, the first section, and/or the second section. Suppose in the map, the i{circumflex over ( )}{th} domain item is mapped to the j{circumflex over ( )}{th} range item. The constraint may be on admissible combination of i and j (constraint on relationship between i and j). Mismatch cost between a first section of a first time duration of a first TSCI and a second section of a second time duration of a second TSCI may be computed. 
     The first section and the second section may be aligned such that a map comprising more than one links may be established between first items of the first TSCI and second items of the second TSCI. With each link, one of the first items with a first timestamp may be associated with one of the second items with a second timestamp. A mismatch cost between the aligned first section and the aligned second section may be computed. The mismatch cost may comprise a function of: an item-wise cost between a first item and a second item associated by a particular link of the map, and a link-wise cost associated with the particular link of the map. 
     The aligned first section and the aligned second section may be represented respectively as a first vector and a second vector of same vector length. The mismatch cost may comprise at least one of: an inner product, inner-product-like quantity, quantity based on correlation, correlation indicator, quantity based on covariance, discriminating score, distance, Euclidean distance, absolute distance, Lk distance (e.g. L1, L2, . . . ), weighted distance, distance-like quantity and/or another similarity value, between the first vector and the second vector. The mismatch cost may be normalized by the respective vector length. 
     A parameter derived from the mismatch cost between the first section of the first time duration of the first TSCI and the second section of the second time duration of the second TSCI may be modeled with a statistical distribution. At least one of: a scale parameter, location parameter and/or another parameter, of the statistical distribution may be estimated. The first section of the first time duration of the first TSCI may be a sliding section of the first TSCI. The second section of the second time duration of the second TSCI may be a sliding section of the second TSCI. A first sliding window may be applied to the first TSCI and a corresponding second sliding window may be applied to the second TSCI. The first sliding window of the first TSCI and the corresponding second sliding window of the second TSCI may be aligned. 
     Mismatch cost between the aligned first sliding window of the first TSCI and the corresponding aligned second sliding window of the second TSCI may be computed. The current event may be associated with at least one of: the known event, the unknown event and/or the another event, based on the mismatch cost. 
     The classifier may be applied to at least one of: each first section of the first time duration of the first TSCI, and/or each second section of the second time duration of the second TSCI, to obtain at least one tentative classification results. Each tentative classification result may be associated with a respective first section and a respective second section. 
     The current event may be associated with at least one of: the known event, the unknown event, a class/category/group/grouping/list/set of unknown events, and/or the another event, based on the mismatch cost. The current event may be associated with at least one of: the known event, the unknown event and/or the another event, based on a largest number of tentative classification results in more than one sections of the first TSCI and corresponding more than sections of the second TSCI. For example, the current event may be associated with a particular known event if the mismatch cost points to the particular known event for N consecutive times (e.g. N=10). In another example, the current event may be associated with a particular known event if the percentage of mismatch cost within the immediate past N consecutive N pointing to the particular known event exceeds a certain threshold (e.g. &gt;80%). In another example, the current event may be associated with a known event that achieves smallest mismatch cost for the most times within a time period. The current event may be associated with a known event that achieves smallest overall mismatch cost, which is a weighted average of at least one mismatch cost associated with the at least one first sections. The current event may be associated with a particular known event that achieves smallest of another overall cost. The current event may be associated with the “unknown event” if none of the known events achieve mismatch cost lower than a first threshold T1 in a sufficient percentage of the at least one first section. The current event may also be associated with the “unknown event” if none of the events achieve an overall mismatch cost lower than a second threshold T2. The current event may be associated with at least one of: the known event, the unknown event and/or the another event, based on the mismatch cost and additional mismatch cost associated with at least one additional section of the first TSCI and at least one additional section of the second TSCI. The known events may comprise at least one of: a door closed event, door open event, window closed event, window open event, multi-state event, on-state event, off-state event, intermediate state event, continuous state event, discrete state event, human-present event, human-absent event, sign-of-life-present event, and/or a sign-of-life-absent event. 
     A projection for each CI may be trained using a dimension reduction method based on the training TSCI. The dimension reduction method may comprise at least one of: principal component analysis (PCA), PCA with different kernel, independent component analysis (ICA), Fisher linear discriminant, vector quantization, supervised learning, unsupervised learning, self-organizing maps, auto-encoder, neural network, deep neural network, and/or another method. The projection may be applied to at least one of: the training TSCI associated with the at least one event, and/or the current TSCI, for the classifier. The classifier of the at least one event may be trained based on the projection and the training TSCI associated with the at least one event. The at least one current TSCI may be classified/categorized based on the projection and the current TSCI. The projection may be re-trained using at least one of: the dimension reduction method, and another dimension reduction method, based on at least one of: the training TSCI, at least one current TSCI before retraining the projection, and/or additional training TSCI. The another dimension reduction method may comprise at least one of: principal component analysis (PCA), PCA with different kernels, independent component analysis (ICA), Fisher linear discriminant, vector quantization, supervised learning, unsupervised learning, self-organizing maps, auto-encoder, neural network, deep neural network, and/or yet another method. The classifier of the at least one event may be re-trained based on at least one of: the re-trained projection, the training TSCI associated with the at least one events, and/or at least one current TSCI. The at least one current TSCI may be classified based on: the re-trained projection, the re-trained classifier, and/or the current TSCI. 
     Each CI may comprise a vector of complex values. Each complex value may be preprocessed to give the magnitude of the complex value. Each CI may be preprocessed to give a vector of non-negative real numbers comprising the magnitude of corresponding complex values. Each training TSCI may be weighted in the training of the projection. The projection may comprise more than one projected components. The projection may comprise at least one most significant projected component. The projection may comprise at least one projected component that may be beneficial for the classifier. 
     The channel information (CI) may be associated with/may comprise signal strength, signal amplitude, signal phase, spectral power measurement, modem parameters (e.g. used in relation to modulation/demodulation in digital communication systems such as WiFi, 4G/LTE), dynamic beamforming information, transfer function components, radio state (e.g. used in digital communication systems to decode digital data, baseband processing state, RF processing state, etc.), measurable variables, sensed data, coarse-grained/fine-grained information of a layer (e.g. physical layer, data link layer, MAC layer, etc.), digital setting, gain setting, RF filter setting, RF front end switch setting, DC offset setting, DC correction setting, IQ compensation setting, effect(s) on the wireless signal by the environment (e.g. venue) during propagation, transformation of an input signal (the wireless signal transmitted by the Type 1 device) to an output signal (the wireless signal received by the Type 2 device), a stable behavior of the environment, a state profile, wireless channel measurements, received signal strength indicator (RSSI), channel state information (CSI), channel impulse response (CIR), channel frequency response (CFR), characteristics of frequency components (e.g. subcarriers) in a bandwidth, channel characteristics, channel filter response, timestamp, auxiliary information, data, meta data, user data, account data, access data, security data, session data, status data, supervisory data, household data, identity (ID), identifier, device data, network data, neighborhood data, environment data, real-time data, sensor data, stored data, encrypted data, compressed data, protected data, and/or another channel information. Each CI may be associated with a time stamp, and/or an arrival time. A CSI can be used to equalize/undo/minimize/reduce the multipath channel effect (of the transmission channel) to demodulate a signal similar to the one transmitted by the transmitter through the multipath channel. The CI may be associated with information associated with a frequency band, frequency signature, frequency phase, frequency amplitude, frequency trend, frequency characteristics, frequency-like characteristics, time domain element, frequency domain element, time-frequency domain element, orthogonal decomposition characteristics, and/or non-orthogonal decomposition characteristics of the signal through the channel. The TSCI may be a stream of wireless signals (e.g. CI). 
     The CI may be preprocessed, processed, postprocessed, stored (e.g. in local memory, portable/mobile memory, removable memory, storage network, cloud memory, in a volatile manner, in a non-volatile manner), retrieved, transmitted and/or received. One or more modem parameters and/or radio state parameters may be held constant. The modem parameters may be applied to a radio subsystem. The modem parameters may represent a radio state. A motion detection signal (e.g. baseband signal, and/or packet decoded/demodulated from the baseband signal, etc.) may be obtained by processing (e.g. down-converting) the first wireless signal (e.g. RF/WiFi/LTE/5G signal) by the radio subsystem using the radio state represented by the stored modem parameters. The modem parameters/radio state may be updated (e.g. using previous modem parameters or previous radio state). Both the previous and updated modem parameters/radio states may be applied in the radio subsystem in the digital communication system. Both the previous and updated modem parameters/radio states may be compared/analyzed/processed/monitored in the task. 
     The channel information may also be modem parameters (e.g. stored or freshly computed) used to process the wireless signal. The wireless signal may comprise a plurality of probe signals. The same modem parameters may be used to process more than one probe signals. The same modem parameters may also be used to process more than one wireless signals. The modem parameters may comprise parameters that indicate settings or an overall configuration for the operation of a radio subsystem or a baseband subsystem of a wireless sensor device (or both). The modem parameters may include one or more of: a gain setting, an RF filter setting, an RF front end switch setting, a DC offset setting, or an IQ compensation setting for a radio subsystem, or a digital DC correction setting, a digital gain setting, and/or a digital filtering setting (e.g. for a baseband subsystem). The CI may also be associated with information associated with a time period, time signature, timestamp, time amplitude, time phase, time trend, and/or time characteristics of the signal. The CI may be associated with information associated with a time-frequency partition, signature, amplitude, phase, trend, and/or characteristics of the signal. The CI may be associated with a decomposition of the signal. The CI may be associated with information associated with a direction, angle of arrival (AoA), angle of a directional antenna, and/or a phase of the signal through the channel. The CI may be associated with attenuation patterns of the signal through the channel. Each CI may be associated with a Type 1 device and a Type 2 device. Each CI may be associated with an antenna of the Type 1 device and an antenna of the Type 2 device. 
     The CI may be obtained from a communication hardware (e.g. of Type 2 device, or Type 1 device) that is capable of providing the CI. The communication hardware may be a WiFi-capable chip/IC (integrated circuit), chip compliant with a 802.11 or 802.16 or another wireless/radio standard, next generation WiFi-capable chip, LTE-capable chip, 5G-capable chip, 6G/7G/8G-capable chip, Bluetooth-enabled chip, NFC (near field communication)-enabled chip, BLE (Bluetooth low power)-enabled chip, UWB chip, another communication chip (e.g. Zigbee, WiMax, mesh network), etc. The communication hardware computes the CI and stores the CI in a buffer memory and make the CI available for extraction. The CI may comprise data and/or at least one matrices related to channel state information (CSI). The at least one matrices may be used for channel equalization, and/or beam forming, etc. The channel may be associated with a venue. The attenuation may be due to signal propagation in the venue, signal propagating/reflection/refraction/diffraction through/at/around air (e.g. air of venue), refraction medium/reflection surface such as wall, doors, furniture, obstacles and/or barriers, etc. The attenuation may be due to reflection at surfaces and obstacles (e.g. reflection surface, obstacle) such as floor, ceiling, furniture, fixtures, objects, people, pets, etc. Each CI may be associated with a timestamp. Each CI may comprise N1 components (e.g. N1 frequency domain components in CFR, N1 time domain components in CIR, or N1 decomposition components). Each component may be associated with a component index. Each component may be a real, imaginary, or complex quantity, magnitude, phase, flag, and/or set. Each CI may comprise a vector or matrix of complex numbers, a set of mixed quantities, and/or a multi-dimensional collection of at least one complex numbers. 
     Components of a TSCI associated with a particular component index may form a respective component time series associated with the respective index. A TSCI may be divided into N1 component time series. Each respective component time series is associated with a respective component index. The characteristics/STI of the motion of the object may be monitored based on the component time series. In one example, one or more ranges of CIC (e.g. one range being from component  11  to component  23 , a second range being from component  44  to component  50 , and a third range having only one component) may be selected based on some criteria/cost function/signal quality metric (e.g. based on signal-to-noise ratio, and/or interference level) for further processing. 
     A component-wise characteristic of a component-feature time series of a TSCI may be computed. The component-wise characteristics may be a scalar (e.g. energy) or a function with a domain and a range (e.g. an autocorrelation function, transform, inverse transform). The characteristics/STI of the motion of the object may be monitored based on the component-wise characteristics. A total characteristics (e.g. aggregate characteristics) of the TSCI may be computed based on the component-wise characteristics of each component time series of the TSCI. The total characteristics may be a weighted average of the component-wise characteristics. The characteristics/STI of the motion of the object may be monitored based on the total characteristics. An aggregate quantity may be a weighted average of individual quantities. 
     The Type 1 device and Type 2 device may support WiFi, WiMax, 3G/beyond 3G, 4G/beyond 4G, LTE, LTE-A, 5G, 6G, 7G, Bluetooth, NFC, BLE, Zigbee, UWB, UMTS, 3GPP, GSM, EDGE, TDMA, FDMA, CDMA, WCDMA, TD-SCDMA, mesh network, proprietary wireless system, IEEE 802.11 standard, 802.15 standard, 802.16 standard, 3GPP standard, and/or another wireless system. 
     A common wireless system and/or a common wireless channel may be shared by the Type 1 transceiver and/or the at least one Type 2 transceiver. The at least one Type 2 transceiver may transmit respective signal contemporaneously (or: asynchronously, synchronously, sporadically, continuously, repeatedly, concurrently, simultaneously and/or temporarily) using the common wireless system and/or the common wireless channel. The Type 1 transceiver may transmit a signal to the at least one Type 2 transceiver using the common wireless system and/or the common wireless channel. 
     Each Type 1 device and Type 2 device may have at least one transmitting/receiving antenna. Each CI may be associated with one of the transmitting antenna of the Type 1 device and one of the receiving antenna of the Type 2 device. Each pair of a transmitting antenna and a receiving antenna may be associated with a link, a path, a communication path, signal hardware path, etc. For example, if the Type 1 device has M (e.g. 3) transmitting antennas, and the Type 2 device has N (e.g. 2) receiving antennas, there may be M×N (e.g. 3×2=6) links or paths. Each link or path may be associated with a TSCI. 
     The at least one TSCI may correspond to various antenna pairs between the Type 1 device and the Type 2 device. The Type 1 device may have at least one antenna. The Type 2 device may also have at least one antenna. Each TSCI may be associated with an antenna of the Type 1 device and an antenna of the Type 2 device. Averaging or weighted averaging over antenna links may be performed. The averaging or weighted averaging may be over the at least one TSCI. The averaging may optionally be performed on a subset of the at least one TSCI corresponding to a subset of the antenna pairs. 
     Timestamps of CI of a portion of a TSCI may be irregular and may be corrected so that corrected timestamps of time-corrected CI may be uniformly spaced in time. In the case of multiple Type 1 devices and/or multiple Type 2 devices, the corrected timestamp may be with respect to the same or different clock. An original timestamp associated with each of the CI may be determined. The original timestamp may not be uniformly spaced in time. Original timestamps of all CI of the particular portion of the particular TSCI in the current sliding time window may be corrected so that corrected timestamps of time-corrected CI may be uniformly spaced in time. 
     The characteristics and/or STI (e.g. motion information) may comprise: location, location coordinate, change in location, position (e.g. initial position, new position), position on map, height, horizontal location, vertical location, distance, displacement, speed, acceleration, rotational speed, rotational acceleration, direction, angle of motion, azimuth, direction of motion, rotation, path, deformation, transformation, shrinking, expanding, gait, gait cycle, head motion, repeated motion, periodic motion, pseudo-periodic motion, impulsive motion, sudden motion, fall-down motion, transient motion, behavior, transient behavior, period of motion, frequency of motion, time trend, temporal profile, temporal characteristics, occurrence, change, temporal change, change of CI, change in frequency, change in timing, change of gait cycle, timing, starting time, initiating time, ending time, duration, history of motion, motion type, motion classification, frequency, frequency spectrum, frequency characteristics, presence, absence, proximity, approaching, receding, identity/identifier of the object, composition of the object, head motion rate, head motion direction, mouth-related rate, eye-related rate, breathing rate, heart rate, tidal volume, depth of breath, inhale time, exhale time, inhale time to exhale time ratio, airflow rate, heart heat-to-beat interval, heart rate variability, hand motion rate, hand motion direction, leg motion, body motion, walking rate, hand motion rate, positional characteristics, characteristics associated with movement (e.g. change in position/location) of the object, tool motion, machine motion, complex motion, and/or combination of multiple motions, event, signal statistics, signal dynamics, anomaly, motion statistics, motion parameter, indication of motion detection, motion magnitude, motion phase, similarity score, distance score, Euclidean distance, weighted distance, L_1 norm, L_2 norm, L_k norm for k&gt;2, statistical distance, correlation, correlation indicator, auto-correlation, covariance, auto-covariance, cross-covariance, inner product, outer product, motion signal transformation, motion feature, presence of motion, absence of motion, motion localization, motion identification, motion recognition, presence of object, absence of object, entrance of object, exit of object, a change of object, motion cycle, motion count, gait cycle, motion rhythm, deformation motion, gesture, handwriting, head motion, mouth motion, heart motion, internal organ motion, motion trend, size, length, area, volume, capacity, shape, form, tag, starting/initiating location, ending location, starting/initiating quantity, ending quantity, event, fall-down event, security event, accident event, home event, office event, factory event, warehouse event, manufacturing event, assembly line event, maintenance event, car-related event, navigation event, tracking event, door event, door-open event, door-close event, window event, window-open event, window-close event, repeatable event, one-time event, consumed quantity, unconsumed quantity, state, physical state, health state, well-being state, emotional state, mental state, another event, analytics, output responses, and/or another information. The characteristics and/or STI may be computed/monitored based on a feature computed from a CI or a TSCI (e.g. feature computation/extraction). A static segment or profile (and/or a dynamic segment/profile) may be identified/computed/analyzed/monitored/extracted/obtained/marked/disclosed/indicated/highlighted/stored/communicated based on an analysis of the feature. The analysis may comprise a motion detection/movement assessment/presence detection. Computational workload may be shared among the Type 1 device, the Type 2 device and another processor. 
     The Type 1 device and/or Type 2 device may be a local device. The local device may be: a smart phone, smart device, TV, sound bar, set-top box, access point, router, repeater, wireless signal repeater/extender, remote control, speaker, fan, refrigerator, microwave, oven, coffee machine, hot water pot, utensil, table, chair, light, lamp, door lock, camera, microphone, motion sensor, security device, fire hydrant, garage door, switch, power adapter, computer, dongle, computer peripheral, electronic pad, sofa, tile, accessory, home device, vehicle device, office device, building device, manufacturing device, watch, glasses, clock, television, oven, air-conditioner, accessory, utility, appliance, smart machine, smart vehicle, internet-of-thing (IoT) device, internet-enabled device, computer, portable computer, tablet, smart house, smart office, smart building, smart parking lot, smart system, and/or another device. 
     Each Type 1 device may be associated with a respective identifier (e.g. ID). Each Type 2 device may also be associated with a respective identify (ID). The ID may comprise: numeral, combination of text and numbers, name, password, account, account ID, web link, web address, index to some information, and/or another ID. The ID may be assigned. The ID may be assigned by hardware (e.g. hardwired, via dongle and/or other hardware), software and/or firmware. The ID may be stored (e.g. in database, in memory, in server (e.g. hub device), in the cloud, stored locally, stored remotely, stored permanently, stored temporarily) and may be retrieved. The ID may be associated with at least one record, account, user, household, address, phone number, social security number, customer number, another ID, another identifier, timestamp, and/or collection of data. The ID and/or part of the ID of a Type 1 device may be made available to a Type 2 device. The ID may be used for registration, initialization, communication, identification, verification, detection, recognition, authentication, access control, cloud access, networking, social networking, logging, recording, cataloging, classification, tagging, association, pairing, transaction, electronic transaction, and/or intellectual property control, by the Type 1 device and/or the Type 2 device. 
     The object may be person, user, subject, passenger, child, older person, baby, sleeping baby, baby in vehicle, patient, worker, high-value worker, expert, specialist, waiter, customer in mall, traveler in airport/train station/bus terminal/shipping terminals, staff/worker/customer service personnel in factory/mall/supermarket/office/workplace, serviceman in sewage/air ventilation system/lift well, lifts in lift wells, elevator, inmate, people to be tracked/monitored, animal, plant, living object, pet, dog, cat, smart phone, phone accessory, computer, tablet, portable computer, dongle, computing accessory, networked devices, WiFi devices, IoT devices, smart watch, smart glasses, smart devices, speaker, keys, smart key, wallet, purse, handbag, backpack, goods, cargo, luggage, equipment, motor, machine, air conditioner, fan, air conditioning equipment, light fixture, moveable light, television, camera, audio and/or video equipment, stationary, surveillance equipment, parts, signage, tool, cart, ticket, parking ticket, toll ticket, airplane ticket, credit card, plastic card, access card, food packaging, utensil, table, chair, cleaning equipment/tool, vehicle, car, cars in parking facilities, merchandise in warehouse/store/supermarket/distribution center, boat, bicycle, airplane, drone, remote control car/plane/boat, robot, manufacturing device, assembly line, material/unfinished part/robot/wagon/transports on factory floor, object to be tracked in airport/shopping mart/supermarket, non-object, absence of an object, presence of an object, object with form, object with changing form, object with no form, mass of fluid, mass of liquid, mass of gas/smoke, fire, flame, electromagnetic (EM) source, EM medium, and/or another object. The object itself may be communicatively coupled with some network, such as WiFi, MiFi, 3G/4G/LTE/5G/6G/7G, Bluetooth, NFC, BLE, WiMax, Zigbee, UMTS, 3GPP, GSM, EDGE, TDMA, FDMA, CDMA, WCDMA, TD-SCDMA, mesh network, adhoc network, and/or other network. The object itself may be bulky with AC power supply, but is moved during installation, cleaning, maintenance, renovation, etc. It may also be installed in moveable platform such as lift, pad, movable, platform, elevator, conveyor belt, robot, drone, forklift, car, boat, vehicle, etc. The object may have multiple parts, each part with different movement (e.g. change in position/location). For example, the object may be a person walking forward. While walking, his left hand and right hand may move in different direction, with different instantaneous speed, acceleration, motion, etc. 
     The wireless transmitter (e.g. Type 1 device), the wireless receiver (e.g. Type 2 device), another wireless transmitter and/or another wireless receiver may move with the object and/or another object (e.g. in prior movement, current movement and/or future movement. They may be communicatively coupled to one or more nearby device. They may transmit TSCI and/or information associated with the TSCI to the nearby device, and/or each other. They may be with the nearby device. The wireless transmitter and/or the wireless receiver may be part of a small (e.g. coin-size, cigarette box size, or even smaller), light-weight portable device. The portable device may be wirelessly coupled with a nearby device. 
     The nearby device may be smart phone, iPhone, Android phone, smart device, smart appliance, smart vehicle, smart gadget, smart TV, smart refrigerator, smart speaker, smart watch, smart glasses, smart pad, iPad, computer, wearable computer, notebook computer, gateway. The nearby device may be connected to a cloud server, local server (e.g. hub device) and/or other server via internet, wired internet connection and/or wireless internet connection. The nearby device may be portable. The portable device, the nearby device, a local server (e.g. hub device) and/or a cloud server may share the computation and/or storage for a task (e.g. obtain TSCI, determine characteristics/STI of the object associated with the movement (e.g. change in position/location) of the object, computation of time series of power (e.g. signal strength) information, determining/computing the particular function, searching for local extremum, classification, identifying particular value of time offset, de-noising, processing, simplification, cleaning, wireless smart sensing task, extract CI from signal, switching, segmentation, estimate trajectory/path/track, process the map, processing trajectory/path/track based on environment models/constraints/limitations, correction, corrective adjustment, adjustment, map-based (or model-based) correction, detecting error, checking for boundary hitting, thresholding) and information (e.g. TSCI). The nearby device may/may not move with the object. The nearby device may be portable/not portable/moveable/non-moveable. The nearby device may use battery power, solar power, AC power and/or other power source. The nearby device may have replaceable/non-replaceable battery, and/or rechargeable/non-rechargeable battery. The nearby device may be similar to the object. The nearby device may have identical (and/or similar) hardware and/or software to the object. The nearby device may be a smart device, network enabled device, device with connection to WiFi/3G/4G/5G/6G/Zigbee/Bluetooth/NFC/UMTS/3GPP/GSM/EDGE/TDMA/FDMA/CDMA/WCDMA/TD-SCDMA/adhoc network/other network, smart speaker, smart watch, smart clock, smart appliance, smart machine, smart equipment, smart tool, smart vehicle, internet-of-thing (IoT) device, internet-enabled device, computer, portable computer, tablet, and another device. The nearby device and/or at least one processor associated with the wireless receiver, the wireless transmitter, the another wireless receiver, the another wireless transmitter and/or a cloud server (in the cloud) may determine the initial STI of the object. Two or more of them may determine the initial spatial-temporal info jointly. Two or more of them may share intermediate information in the determination of the initial STI (e.g. initial position). 
     In one example, the wireless transmitter (e.g. Type 1 device, or Tracker Bot) may move with the object. The wireless transmitter may send the signal to the wireless receiver (e.g. Type 2 device, or Origin Register) or determining the initial STI (e.g. initial position) of the object. The wireless transmitter may also send the signal and/or another signal to another wireless receiver (e.g. another Type 2 device, or another Origin Register) for the monitoring of the motion (spatial-temporal info) of the object. The wireless receiver may also receive the signal and/or another signal from the wireless transmitter and/or the another wireless transmitter for monitoring the motion of the object. The location of the wireless receiver and/or the another wireless receiver may be known. In another example, the wireless receiver (e.g. Type 2 device, or Tracker Bot) may move with the object. The wireless receiver may receive the signal transmitted from the wireless transmitter (e.g. Type 1 device, or Origin Register) for determining the initial spatial-temporal info (e.g. initial position) of the object. The wireless receiver may also receive the signal and/or another signal from another wireless transmitter (e.g. another Type 1 device, or another Origin Register) for the monitoring of the current motion (e.g. spatial-temporal info) of the object. The wireless transmitter may also transmit the signal and/or another signal to the wireless receiver and/or the another wireless receiver (e.g. another Type 2 device, or another Tracker Bot) for monitoring the motion of the object. The location of the wireless transmitter and/or the another wireless transmitter may be known. 
     The venue may be a space such as a sensing area, room, house, office, property, workplace, hallway, walkway, lift, lift well, escalator, elevator, sewage system, air ventilations system, staircase, gathering area, duct, air duct, pipe, tube, enclosed space, enclosed structure, semi-enclosed structure, enclosed area, area with at least one wall, plant, machine, engine, structure with wood, structure with glass, structure with metal, structure with walls, structure with doors, structure with gaps, structure with reflection surface, structure with fluid, building, rooftop, store, factory, assembly line, hotel room, museum, classroom, school, university, government building, warehouse, garage, mall, airport, train station, bus terminal, hub, transportation hub, shipping terminal, government facility, public facility, school, university, entertainment facility, recreational facility, hospital, pediatric/neonatal wards, seniors home, elderly care facility, geriatric facility, community center, stadium, playground, park, field, sports facility, swimming facility, track and/or field, basketball court, tennis court, soccer stadium, baseball stadium, gymnasium, hall, garage, shopping mart, mall, supermarket, manufacturing facility, parking facility, construction site, mining facility, transportation facility, highway, road, valley, forest, wood, terrain, landscape, den, patio, land, path, amusement park, urban area, rural area, suburban area, metropolitan area, garden, square, plaza, music hall, downtown facility, over-air facility, semi-open facility, closed area, train platform, train station, distribution center, warehouse, store, distribution center, storage facility, underground facility, space (e.g. above ground, outer-space) facility, floating facility, cavern, tunnel facility, indoor facility, open-air facility, outdoor facility with some walls/doors/reflective barriers, open facility, semi-open facility, car, truck, bus, van, container, ship/boat, submersible, train, tram, airplane, vehicle, mobile home, cave, tunnel, pipe, channel, metropolitan area, downtown area with relatively tall buildings, valley, well, duct, pathway, gas line, oil line, water pipe, network of interconnecting pathways/alleys/roads/tubes/cavities/caves/pipe-like structure/air space/fluid space, human body, animal body, body cavity, organ, bone, teeth, soft tissue, hard tissue, rigid tissue, non-rigid tissue, blood/body fluid vessel, windpipe, air duct, den, etc. The venue may be indoor space, outdoor space, The venue may include both the inside and outside of the space. For example, the venue may include both the inside of a building and the outside of the building. For example, the venue can be a building that has one floor or multiple floors, and a portion of the building can be underground. The shape of the building can be, e.g., round, square, rectangular, triangle, or irregular-shaped. These are merely examples. The disclosure can be used to detect events in other types of venue or spaces. 
     The wireless transmitter (e.g. Type 1 device) and/or the wireless receiver (e.g. Type 2 device) may be embedded in a portable device (e.g. a module, or a device with the module) that may move with the object (e.g. in prior movement and/or current movement). The portable device may be communicatively coupled with the object using a wired connection (e.g. through USB, microUSB, Firewire, HDMI, serial port, parallel port, and other connectors) and/or a connection (e.g. Bluetooth, Bluetooth Low Energy (BLE), WiFi, LTE, NFC, ZigBee). The portable device may be a lightweight device. The portable may be powered by battery, rechargeable battery and/or AC power. The portable device may be very small (e.g. at sub-millimeter scale and/or sub-centimeter scale), and/or small (e.g. coin-size, card-size, pocket-size, or larger). The portable device may be large, sizable, and/or bulky (e.g. heavy machinery to be installed). The portable device may be a WiFi hotspot, access point, mobile WiFi (MiFi), dongle with USB/micro USB/Firewire/other connector, smartphone, portable computer, computer, tablet, smart device, internet-of-thing (IoT) device, WiFi-enabled device, LTE-enabled device, a smart watch, smart glass, smart mirror, smart antenna, smart battery, smart light, smart pen, smart ring, smart door, smart window, smart clock, small battery, smart wallet, smart belt, smart handbag, smart clothing/garment, smart ornament, smart packaging, smart paper/book/magazine/poster/printed matter/signage/display/lighted system/lighting system, smart key/tool, smart bracelet/chain/necklace/wearable/accessory, smart pad/cushion, smart tile/block/brick/building material/other material, smart garbage can/waste container, smart food carriage/storage, smart ball/racket, smart chair/sofa/bed, smart shoe/footwear/carpet/mat/shoe rack, smart glove/hand wear/ring/hand ware, smart hat/headwear/makeup/sticker/tattoo, smart mirror, smart toy, smart pill, smart utensil, smart bottle/food container, smart tool, smart device, IoT device, WiFi enabled device, network enabled device, 3G/4G/5G/6G enabled device, UMTS devices, 3GPP devices, GSM devices, EDGE devices, TDMA devices, FDMA devices, CDMA devices, WCDMA devices, TD-SCDMA devices, embeddable device, implantable device, air conditioner, refrigerator, heater, furnace, furniture, oven, cooking device, television/set-top box (STB)/DVD player/audio player/video player/remote control, hi-fi, audio device, speaker, lamp/light, wall, door, window, roof, roof tile/shingle/structure/attic structure/device/feature/installation/fixtures, lawn mower/garden tools/yard tools/mechanics tools/garage tools/, garbage can/container, 20-ft/40-ft container, storage container, factory/manufacturing/production device, repair tools, fluid container, machine, machinery to be installed, vehicle, cart, wagon, warehouse vehicle, car, bicycle, motorcycle, boat, vessel, airplane, basket/box/bag/bucket/container, smart plate/cup/bowl/pot/mat/utensils/kitchen tools/kitchen devices/kitchen accessories/cabinets/tables/chairs/tiles/lights/water pipes/taps/gas range/oven/dishwashing machine/etc. The portable device may have a battery that may be replaceable, irreplaceable, rechargeable, and/or non-rechargeable. The portable device may be wirelessly charged. The portable device may be a smart payment card. The portable device may be a payment card used in parking lots, highways, entertainment parks, or other venues/facilities that need payment. The portable device may have an identity (ID)/identifier as described above. 
     An event may be monitored based on the TSCI. The event may be an object related event, such as fall-down of the object (e.g. an person and/or a sick person), rotation, hesitation, pause, impact (e.g. a person hitting a sandbag, door, window, bed, chair, table, desk, cabinet, box, another person, animal, bird, fly, table, chair, ball, bowling ball, tennis ball, football, soccer ball, baseball, basketball, volley ball), two-body action (e.g. a person letting go a balloon, catching a fish, molding a clay, writing a paper, person typing on a computer), car moving in a garage, person carrying a smart phone and walking around an airport/mall/government building/office/etc., autonomous moveable object/machine moving around (e.g. vacuum cleaner, utility vehicle, car, drone, self-driving car). The task or the wireless smart sensing task may comprise: object detection, presence detection, proximity detection, object recognition, activity recognition, object verification, object counting, daily activity monitoring, well-being monitoring, vital sign monitoring, health condition monitoring, baby monitoring, elderly monitoring, sleep monitoring, sleep stage monitoring, walking monitoring, exercise monitoring, tool detection, tool recognition, tool verification, patient detection, patient monitoring, patient verification, machine detection, machine recognition, machine verification, human detection, human recognition, human verification, baby detection, baby recognition, baby verification, human breathing detection, human breathing recognition, human breathing estimation, human breathing verification, human heart beat detection, human heart beat recognition, human heart beat estimation, human heart beat verification, fall-down detection, fall-down recognition, fall-down estimation, fall-down verification, emotion detection, emotion recognition, emotion estimation, emotion verification, motion detection, motion degree estimation, motion recognition, motion estimation, motion verification, periodic motion detection, periodic motion recognition, periodic motion estimation, periodic motion verification, repeated motion detection, repeated motion recognition, repeated motion estimation, repeated motion verification, stationary motion detection, stationary motion recognition, stationary motion estimation, stationary motion verification, cyclo-stationary motion detection, cyclo-stationary motion recognition, cyclo-stationary motion estimation, cyclo-stationary motion verification, transient motion detection, transient motion recognition, transient motion estimation, transient motion verification, trend detection, trend recognition, trend estimation, trend verification, breathing detection, breathing recognition, breathing estimation, breathing estimation, human biometrics detection, human biometric recognition, human biometrics estimation, human biometrics verification, environment informatics detection, environment informatics recognition, environment informatics estimation, environment informatics verification, gait detection, gait recognition, gait estimation, gait verification, gesture detection, gesture recognition, gesture estimation, gesture verification, machine learning, supervised learning, unsupervised learning, semi-supervised learning, clustering, feature extraction, featuring training, principal component analysis, eigen-decomposition, frequency decomposition, time decomposition, time-frequency decomposition, functional decomposition, other decomposition, training, discriminative training, supervised training, unsupervised training, semi-supervised training, neural network, sudden motion detection, fall-down detection, danger detection, life-threat detection, regular motion detection, stationary motion detection, cyclo-stationary motion detection, intrusion detection, suspicious motion detection, security, safety monitoring, navigation, guidance, map-based processing, map-based correction, model-based processing/correction, irregularity detection, locationing, room sensing, tracking, multiple object tracking, indoor tracking, indoor position, indoor navigation, energy management, power transfer, wireless power transfer, object counting, car tracking in parking garage, activating a device/system (e.g. security system, access system, alarm, siren, speaker, television, entertaining system, camera, heater/air-conditioning (HVAC) system, ventilation system, lighting system, gaming system, coffee machine, cooking device, cleaning device, housekeeping device), geometry estimation, augmented reality, wireless communication, data communication, signal broadcasting, networking, coordination, administration, encryption, protection, cloud computing, other processing and/or other task. The task may be performed by the Type 1 device, the Type 2 device, another Type 1 device, another Type 2 device, a nearby device, a local server (e.g. hub device), edge server, a cloud server, and/or another device. The task may be based on TSCI between any pair of Type 1 device and Type 2 device. A Type 2 device may be a Type 1 device, and vice versa. A Type 2 device may play/perform the role (e.g. functionality) of Type 1 device temporarily, continuously, sporadically, simultaneously, and/or contemporaneously, and vice versa. A first part of the task may comprise at least one of: preprocessing, processing, signal conditioning, signal processing, post-processing, processing sporadically/continuously/simultaneously/contemporaneously/dynamically/adaptivel on-demand/as-needed, calibrating, denoising, feature extraction, coding, encryption, transformation, mapping, motion detection, motion estimation, motion change detection, motion pattern detection, motion pattern estimation, motion pattern recognition, vital sign detection, vital sign estimation, vital sign recognition, periodic motion detection, periodic motion estimation, repeated motion detection/estimation, breathing rate detection, breathing rate estimation, breathing pattern detection, breathing pattern estimation, breathing pattern recognition, heart beat detection, heart beat estimation, heart pattern detection, heart pattern estimation, heart pattern recognition, gesture detection, gesture estimation, gesture recognition, speed detection, speed estimation, object locationing, object tracking, navigation, acceleration estimation, acceleration detection, fall-down detection, change detection, intruder (and/or illegal action) detection, baby detection, baby monitoring, patient monitoring, object recognition, wireless power transfer, and/or wireless charging. 
     A second part of the task may comprise at least one of: a smart home task, smart office task, smart building task, smart factory task (e.g. manufacturing using a machine or an assembly line), smart internet-of-thing (IoT) task, smart system task, smart home operation, smart office operation, smart building operation, smart manufacturing operation (e.g. moving supplies/parts/raw material to a machine/an assembly line), IoT operation, smart system operation, turning on a light, turning off the light, controlling the light in at least one of: a room, region, and/or the venue, playing a sound clip, playing the sound clip in at least one of: the room, the region, and/or the venue, playing the sound clip of at least one of: a welcome, greeting, farewell, first message, and/or a second message associated with the first part of the task, turning on an appliance, turning off the appliance, controlling the appliance in at least one of: the room, the region, and/or the venue, turning on an electrical system, turning off the electrical system, controlling the electrical system in at least one of: the room, the region, and/or the venue, turning on a security system, turning off the security system, controlling the security system in at least one of: the room, the region, and/or the venue, turning on a mechanical system, turning off a mechanical system, controlling the mechanical system in at least one of: the room, the region, and/or the venue, and/or controlling at least one of: an air conditioning system, heating system, ventilation system, lighting system, heating device, stove, entertainment system, door, fence, window, garage, computer system, networked device, networked system, home appliance, office equipment, lighting device, robot (e.g. robotic arm), smart vehicle, smart machine, assembly line, smart device, internet-of-thing (IoT) device, smart home device, and/or a smart office device. 
     The task may include: detect a user returning home, detect a user leaving home, detect a user moving from one room to another, detect/control/lock/unlock/open/close/partially open a window/door/garage door/blind/curtain/panel/solar panel/sun shade, detect a pet, detect/monitor a user doing something (e.g. sleeping on sofa, sleeping in bedroom, running on treadmill, cooking, sitting on sofa, watching TV, eating in kitchen, eating in dining room, going upstairs/downstairs, going outside/coming back, in the rest room), monitor/detect location of a user/pet, do something (e.g. send a message, notify/report to someone) automatically upon detection, do something for the user automatically upon detecting the user, turn on/off/dim a light, turn on/off music/radio/home entertainment system, turn on/off/adjust/control TV/HiFi/set-top-box (STB)/home entertainment system/smart speaker/smart device, turn on/off/adjust air conditioning system, turn on/off/adjust ventilation system, turn on/off/adjust heating system, adjust/control curtains/light shades, turn on/off/wake a computer, turn on/off/pre-heat/control coffee machine/hot water pot, turn on/off/control/preheat cooker/oven/microwave oven/another cooking device, check/adjust temperature, check weather forecast, check telephone message box, check mail, do a system check, control/adjust a system, check/control/arm/disarm security system/baby monitor, check/control refrigerator, give a report (e.g. through a speaker such as Google home, Amazon Echo, on a display/screen, via a webpage/email/messaging system/notification system). 
     For example, when a user arrives home in his car, the task may be to, automatically, detect the user or his car approaching, open the garage door upon detection, turn on the driveway/garage light as the user approaches the garage, turn on air conditioner/heater/fan, etc. As the user enters the house, the task may be to, automatically, turn on the entrance light, turn off driveway/garage light, play a greeting message to welcome the user, turn on the music, turn on the radio and tuning to the user&#39;s favorite radio news channel, open the curtain/blind, monitor the user&#39;s mood, adjust the lighting and sound environment according to the user&#39;s mood or the current/imminent event (e.g. do romantic lighting and music because the user is scheduled to eat dinner with girlfriend in 1 hour) on the user&#39;s daily calendar, warm the food in microwave that the user prepared in the morning, do a diagnostic check of all systems in the house, check weather forecast for tomorrow&#39;s work, check news of interest to the user, check user&#39;s calendar and to-do list and play reminder, check telephone answer system/messaging system/email and give a verbal report using dialog system/speech synthesis, remind (e.g. using audible tool such as speakers/HiFi/speech synthesis/sound/voice/music/song/sound field/background sound field/dialog system, using visual tool such as TV/entertainment system/computer/notebook/smart pad/display/light/color/brightness/patterns/symbols, using haptic tool/virtual reality tool/gesture/tool, using a smart device/appliance/material/furniture/fixture, using web tool/server/hub device/cloud server/fog server/edge server/home network/mesh network, using messaging tool/notification tool/communication tool/scheduling tool/email, using user interface/GUI, using scent/smell/fragrance/taste, using neural tool/nervous system tool, using a combination) the user of his mother&#39;s birthday and to call her, prepare a report, and give the report (e.g. using a tool for reminding as discussed above). The task may turn on the air conditioner/heater/ventilation system in advance, or adjust temperature setting of smart thermostat in advance, etc. As the user moves from the entrance to the living room, the task may be to turn on the living room light, open the living room curtain, open the window, turn off the entrance light behind the user, turn on the TV and set-top box, set TV to the user&#39;s favorite channel, adjust an appliance according to the user&#39;s preference and conditions/states (e.g. adjust lighting and choose/play music to build a romantic atmosphere), etc. 
     Another example may be: When the user wakes up in the morning, the task may be to detect the user moving around in the bedroom, open the blind/curtain, open the window, turn off the alarm clock, adjust indoor temperature from night-time temperature profile to day-time temperature profile, turn on the bedroom light, turn on the restroom light as the user approaches the restroom, check radio or streaming channel and play morning news, turn on the coffee machine and preheat the water, turn off security system, etc. When the user walks from bedroom to kitchen, the task may be to turn on the kitchen and hallway lights, turn off the bedroom and restroom lights, move the music/message/reminder from the bedroom to the kitchen, turn on the kitchen TV, change TV to morning news channel, lower the kitchen blind and open the kitchen window to bring in fresh air, unlock backdoor for the user to check the backyard, adjust temperature setting for the kitchen, etc. Another example may be: When the user leaves home for work, the task may be to detect the user leaving, play a farewell and/or have-a-good-day message, open/close garage door, turn on/off garage light and driveway light, turn off/dim lights to save energy (just in case the user forgets), close/lock all windows/doors (just in case the user forgets), turn off appliance (especially stove, oven, microwave oven), turn on/arm the home security system to guard the home against any intruder, adjust air conditioning/heating/ventilation systems to “away-from-home” profile to save energy, send alerts/reports/updates to the user&#39;s smart phone, etc. 
     A motion may comprise at least one of: a no-motion, resting motion, non-moving motion, movement, change in position/location, deterministic motion, transient motion, fall-down motion, repeating motion, periodic motion, pseudo-periodic motion, periodic/repeated motion associated with breathing, periodic/repeated motion associated with heartbeat, periodic/repeated motion associated with living object, periodic/repeated motion associated with machine, periodic/repeated motion associated with man-made object, periodic/repeated motion associated with nature, complex motion with transient element and periodic element, repetitive motion, non-deterministic motion, probabilistic motion, chaotic motion, random motion, complex motion with non-deterministic element and deterministic element, stationary random motion, pseudo-stationary random motion, cyclo-stationary random motion, non-stationary random motion, stationary random motion with periodic autocorrelation function (ACF), random motion with periodic ACF for period of time, random motion that is pseudo-stationary for a period of time, random motion of which an instantaneous ACF has a pseudo-periodic/repeating element for a period of time, machine motion, mechanical motion, vehicle motion, drone motion, air-related motion, wind-related motion, weather-related motion, water-related motion, fluid-related motion, ground-related motion, change in electro-magnetic characteristics, sub-surface motion, seismic motion, plant motion, animal motion, human motion, normal motion, abnormal motion, dangerous motion, warning motion, suspicious motion, rain, fire, flood, tsunami, explosion, collision, imminent collision, human body motion, head motion, facial motion, eye motion, mouth motion, tongue motion, neck motion, finger motion, hand motion, arm motion, shoulder motion, body motion, chest motion, abdominal motion, hip motion, leg motion, foot motion, body joint motion, knee motion, elbow motion, upper body motion, lower body motion, skin motion, below-skin motion, subcutaneous tissue motion, blood vessel motion, intravenous motion, organ motion, heart motion, lung motion, stomach motion, intestine motion, bowel motion, eating motion, breathing motion, facial expression, eye expression, mouth expression, talking motion, singing motion, eating motion, gesture, hand gesture, arm gesture, keystroke, typing stroke, user-interface gesture, man-machine interaction, gait, dancing movement, coordinated movement, and/or coordinated body movement. 
     The heterogeneous IC of the Type 1 device and/or any Type 2 receiver may comprise low-noise amplifier (LNA), power amplifier, transmit-receive switch, media access controller, baseband radio, 2.4 GHz radio, 3.65 GHz radio, 4.9 GHz radio, 5 GHz radio, 5.9 GHz radio, below 6 GHz radio, below 60 GHz radio and/or another radio. The heterogeneous IC may comprise a processor, a memory communicatively coupled with the processor, and a set of instructions stored in the memory to be executed by the processor. The IC and/or any processor may comprise at least one of: general purpose processor, special purpose processor, microprocessor, multi-processor, multi-core processor, parallel processor, CISC processor, RISC processor, microcontroller, central processing unit (CPU), graphical processor unit (GPU), digital signal processor (DSP), application specific integrated circuit (ASIC), field programmable gate array (FPGA), embedded processor (e.g. ARM), logic circuit, other programmable logic device, discrete logic, and/or a combination. The heterogeneous IC may support broadband network, wireless network, mobile network, mesh network, cellular network, wireless local area network (WLAN), wide area network (WAN), and metropolitan area network (MAN), WLAN standard, WiFi, LTE, LTE-A, LTE-U, 802.11 standard, 802.11a, 802.11b, 802.11g, 802.11n, 802.11ac, 802.11ad, 802.11af, 802.11ah, 802.11ax, 802.11ay, mesh network standard, 802.15 standard, 802.16 standard, cellular network standard, 3G, 3.5G, 4G, beyond 4G, 4.5G, 5G, 6G, 7G, 8G, 9G, UMTS, 3GPP, GSM, EDGE, TDMA, FDMA, CDMA, WCDMA, TD-SCDMA, Bluetooth, Bluetooth Low-Energy (BLE), NFC, Zigbee, WiMax, and/or another wireless network protocol. 
     The processor may comprise general purpose processor, special purpose processor, microprocessor, microcontroller, embedded processor, digital signal processor, central processing unit (CPU), graphical processing unit (GPU), multi-processor, multi-core processor, and/or processor with graphics capability, and/or a combination. The memory may be volatile, non-volatile, random access memory (RAM), Read Only Memory (ROM), Electrically Programmable ROM (EPROM), Electrically Erasable Programmable ROM (EEPROM), hard disk, flash memory, CD-ROM, DVD-ROM, magnetic storage, optical storage, organic storage, storage system, storage network, network storage, cloud storage, edge storage, local storage, external storage, internal storage, or other form of non-transitory storage medium known in the art. The set of instructions (machine executable code) corresponding to the method steps may be embodied directly in hardware, in software, in firmware, or in combinations thereof. The set of instructions may be embedded, pre-loaded, loaded upon boot up, loaded on the fly, loaded on demand, pre-installed, installed, and/or downloaded. 
     The presentation may be a presentation in an audio-visual way (e.g. using combination of visual, graphics, text, symbols, color, shades, video, animation, sound, speech, audio, etc.), graphical way (e.g. using GUI, animation, video), textual way (e.g. webpage with text, message, animated text), symbolic way (e.g. emoticon, signs, hand gesture), or mechanical way (e.g. vibration, actuator movement, haptics, etc.). 
     Computational workload associated with the method is shared among the processor, the Type 1 heterogeneous wireless device, the Type 2 heterogeneous wireless device, a local server (e.g. hub device), a cloud server, and another processor. 
     An operation, pre-processing, processing and/or postprocessing may be applied to data (e.g. TSCI, autocorrelation, features of TSCI). An operation may be preprocessing, processing and/or postprocessing. The preprocessing, processing and/or postprocessing may be an operation. An operation may comprise preprocessing, processing, post-processing, scaling, computing a confidence factor, computing a line-of-sight (LOS) quantity, computing a non-LOS (NLOS) quantity, a quantity comprising LOS and NLOS, computing a single link (e.g. path, communication path, link between a transmitting antenna and a receiving antenna) quantity, computing a quantity comprising multiple links, computing a function of the operands, filtering, linear filtering, nonlinear filtering, folding, grouping, energy computation, lowpass filtering, bandpass filtering, highpass filtering, median filtering, rank filtering, quartile filtering, percentile filtering, mode filtering, finite impulse response (FIR) filtering, infinite impulse response (IIR) filtering, moving average (MA) filtering, autoregressive (AR) filtering, autoregressive moving averaging (ARMA) filtering, selective filtering, adaptive filtering, interpolation, decimation, subsampling, upsampling, resampling, time correction, time base correction, phase correction, magnitude correction, phase cleaning, magnitude cleaning, matched filtering, enhancement, restoration, denoising, smoothing, signal conditioning, enhancement, restoration, spectral analysis, linear transform, nonlinear transform, inverse transform, frequency transform, inverse frequency transform, Fourier transform (FT), discrete time FT (DTFT), discrete FT (DFT), fast FT (FFT), wavelet transform, Laplace transform, Hilbert transform, Hadamard transform, trigonometric transform, sine transform, cosine transform, DCT, power-of-2 transform, sparse transform, graph-based transform, graph signal processing, fast transform, a transform combined with zero padding, cyclic padding, padding, zero padding, feature extraction, decomposition, projection, orthogonal projection, non-orthogonal projection, over-complete projection, eigen-decomposition, singular value decomposition (SVD), principle component analysis (PCA), independent component analysis (ICA), grouping, sorting, thresholding, soft thresholding, hard thresholding, clipping, soft clipping, first derivative, second order derivative, high order derivative, convolution, multiplication, division, addition, subtraction, integration, maximization, minimization, least mean square error, recursive least square, constrained least square, batch least square, least absolute error, least mean square deviation, least absolute deviation, local maximization, local minimization, optimization of a cost function, neural network, recognition, labeling, training, clustering, machine learning, supervised learning, unsupervised learning, semi-supervised learning, comparison with another TSCI, similarity score computation, quantization, vector quantization, matching pursuit, compression, encryption, coding, storing, transmitting, normalization, temporal normalization, frequency domain normalization, classification, clustering, labeling, tagging, learning, detection, estimation, learning network, mapping, remapping, expansion, storing, retrieving, transmitting, receiving, representing, merging, combining, splitting, tracking, monitoring, matched filtering, Kalman filtering, particle filter, intrapolation, extrapolation, histogram estimation, importance sampling, Monte Carlo sampling, compressive sensing, representing, merging, combining, splitting, scrambling, error protection, forward error correction, doing nothing, time varying processing, conditioning averaging, weighted averaging, arithmetic mean, geometric mean, harmonic mean, averaging over selected frequency, averaging over antenna links, logical operation, permutation, combination, sorting, AND, OR, XOR, union, intersection, vector addition, vector subtraction, vector multiplication, vector division, inverse, norm, distance, and/or another operation. The operation may be the preprocessing, processing, and/or post-processing. Operations may be applied jointly on multiple time series or functions. 
     The function (e.g. function of operands) may comprise: scalar function, vector function, discrete function, continuous function, polynomial function, characteristics, feature, magnitude, phase, exponential function, logarithmic function, trigonometric function, transcendental function, logical function, linear function, algebraic function, nonlinear function, piecewise linear function, real function, complex function, vector-valued function, inverse function, derivative of function, integration of function, circular function, function of another function, one-to-one function, one-to-many function, many-to-one function, many-to-many function, zero crossing, absolute function, indicator function, mean, mode, median, range, statistics, histogram, variance, standard deviation, measure of variation, spread, dispersion, deviation, divergence, range, interquartile range, total variation, absolute deviation, total deviation, arithmetic mean, geometric mean, harmonic mean, trimmed mean, percentile, square, cube, root, power, sine, cosine, tangent, cotangent, secant, cosecant, elliptical function, parabolic function, hyperbolic function, game function, zeta function, absolute value, thresholding, limiting function, floor function, rounding function, sign function, quantization, piecewise constant function, composite function, function of function, time function processed with an operation (e.g. filtering), probabilistic function, stochastic function, random function, ergodic function, stationary function, deterministic function, periodic function, repeated function, transformation, frequency transform, inverse frequency transform, discrete time transform, Laplace transform, Hilbert transform, sine transform, cosine transform, triangular transform, wavelet transform, integer transform, power-of-2 transform, sparse transform, projection, decomposition, principle component analysis (PCA), independent component analysis (ICA), neural network, feature extraction, moving function, function of moving window of neighboring items of time series, filtering function, convolution, mean function, histogram, variance/standard deviation function, statistical function, short-time transform, discrete transform, discrete Fourier transform, discrete cosine transform, discrete sine transform, Hadamard transform, eigen-decomposition, eigenvalue, singular value decomposition (SVD), singular value, orthogonal decomposition, matching pursuit, sparse transform, sparse approximation, any decomposition, graph-based processing, graph-based transform, graph signal processing, classification, identifying a class/group/category, labeling, learning, machine learning, detection, estimation, feature extraction, learning network, feature extraction, denoising, signal enhancement, coding, encryption, mapping, remapping, vector quantization, lowpass filtering, highpass filtering, bandpass filtering, matched filtering, Kalman filtering, preprocessing, postprocessing, particle filter, FIR filtering, IIR filtering, autoregressive (AR) filtering, adaptive filtering, first order derivative, high order derivative, integration, zero crossing, smoothing, median filtering, mode filtering, sampling, random sampling, resampling function, downsampling, down-converting, upsampling, up-converting, interpolation, extrapolation, importance sampling, Monte Carlo sampling, compressive sensing, statistics, short term statistics, long term statistics, autocorrelation function, cross correlation, moment generating function, time averaging, weighted averaging, special function, Bessel function, error function, complementary error function, Beta function, Gamma function, integral function, Gaussian function, Poisson function, etc. Machine learning, training, discriminative training, deep learning, neural network, continuous time processing, distributed computing, distributed storage, acceleration using GPU/DSP/coprocessor/multicore/multiprocessing may be applied to a step (or each step) of this disclosure. 
     A frequency transform may include Fourier transform, Laplace transform, Hadamard transform, Hilbert transform, sine transform, cosine transform, triangular transform, wavelet transform, integer transform, power-of-2 transform, combined zero padding and transform, Fourier transform with zero padding, and/or another transform. Fast versions and/or approximated versions of the transform may be performed. The transform may be performed using floating point, and/or fixed point arithmetic. 
     An inverse frequency transform may include inverse Fourier transform, inverse Laplace transform, inverse Hadamard transform, inverse Hilbert transform, inverse sine transform, inverse cosine transform, inverse triangular transform, inverse wavelet transform, inverse integer transform, inverse power-of-2 transform, combined zero padding and transform, inverse Fourier transform with zero padding, and/or another transform. Fast versions and/or approximated versions of the transform may be performed. The transform may be performed using floating point, and/or fixed point arithmetic. 
     A quantity/feature from a TSCI may be computed. The quantity may comprise statistic of at least one of: motion, location, map coordinate, height, speed, acceleration, movement angle, rotation, size, volume, time trend, pattern, one-time pattern, repeating pattern, evolving pattern, time pattern, mutually excluding patterns, related/correlated patterns, cause-and-effect, correlation, short-term/long-term correlation, tendency, inclination, statistics, typical behavior, atypical behavior, time trend, time profile, periodic motion, repeated motion, repetition, tendency, change, abrupt change, gradual change, frequency, transient, breathing, gait, action, event, suspicious event, dangerous event, alarming event, warning, belief, proximity, collision, power, signal, signal power, signal strength, signal intensity, received signal strength indicator (RSSI), signal amplitude, signal phase, signal frequency component, signal frequency band component, channel state information (CSI), map, time, frequency, time-frequency, decomposition, orthogonal decomposition, non-orthogonal decomposition, tracking, breathing, heart beat, statistical parameters, cardiopulmonary statistics/analytics (e.g. output responses), daily activity statistics/analytics, chronic disease statistics/analytics, medical statistics/analytics, an early (or instantaneous or contemporaneous or delayed) indication/suggestion/sign/indicator/verifier/detection/symptom of a disease/condition/situation, biometric, baby, patient, machine, device, temperature, vehicle, parking lot, venue, lift, elevator, spatial, road, fluid flow, home, room, office, house, building, warehouse, storage, system, ventilation, fan, pipe, duct, people, human, car, boat, truck, airplane, drone, downtown, crowd, impulsive event, cyclo-stationary, environment, vibration, material, surface, 3-dimensional, 2-dimensional, local, global, presence, and/or another measurable quantity/variable. 
     Sliding time window may have time varying window width. It may be smaller at the beginning to enable fast acquisition and may increase over time to a steady-state size. The steady-state size may be related to the frequency, repeated motion, transient motion, and/or STI to be monitored. Even in steady state, the window size may be adaptively (and/or dynamically) changed (e.g. adjusted, varied, modified) based on battery life, power consumption, available computing power, change in amount of targets, the nature of motion to be monitored, etc. 
     The time shift between two sliding time windows at adjacent time instance may be constant/variable/locally adaptive/dynamically adjusted over time. When shorter time shift is used, the update of any monitoring may be more frequent which may be used for fast changing situations, object motions, and/or objects. Longer time shift may be used for slower situations, object motions, and/or objects. The window width/size and/or time shift may be changed (e.g. adjusted, varied, modified) upon a user request/choice. The time shift may be changed automatically (e.g. as controlled by processor/computer/server/hub device/cloud server) and/or adaptively (and/or dynamically). 
     At least one characteristics (e.g. characteristic value, or characteristic point) of a function (e.g. auto-correlation function, auto-covariance function, cross-correlation function, cross-covariance function, power spectral density, time function, frequency domain function, frequency transform) may be determined (e.g. by an object tracking server, the processor, the Type 1 heterogeneous device, the Type 2 heterogeneous device, and/or another device). The at least one characteristics of the function may include: a maximum, minimum, extremum, local maximum, local minimum, local extremum, local extremum with positive time offset, first local extremum with positive time offset, n{circumflex over ( )}th local extremum with positive time offset, local extremum with negative time offset, first local extremum with negative time offset, n{circumflex over ( )}th local extremum with negative time offset, constrained maximum, constrained minimum, constrained extremum, significant maximum, significant minimum, significant extremum, slope, derivative, higher order derivative, maximum slope, minimum slope, local maximum slope, local maximum slope with positive time offset, local minimum slope, constrained maximum slope, constrained minimum slope, maximum higher order derivative, minimum higher order derivative, constrained higher order derivative, zero-crossing, zero crossing with positive time offset, n{circumflex over ( )}th zero crossing with positive time offset, zero crossing with negative time offset, n{circumflex over ( )}th zero crossing with negative time offset, constrained zero-crossing, zero-crossing of slope, zero-crossing of higher order derivative, and/or another characteristics. At least one argument of the function associated with the at least one characteristics of the function may be identified. Some quantity (e.g. spatial-temporal information of the object) may be determined based on the at least one argument of the function. 
     A characteristics (e.g. characteristics of motion of an object in the venue) may comprise at least one of: an instantaneous characteristics, short-term characteristics, repetitive characteristics, recurring characteristics, history, incremental characteristics, changing characteristics, deviational characteristics, phase, magnitude, degree, time characteristics, frequency characteristics, time-frequency characteristics, decomposition characteristics, orthogonal decomposition characteristics, non-orthogonal decomposition characteristics, deterministic characteristics, probabilistic characteristics, stochastic characteristics, autocorrelation function (ACF), mean, variance, standard deviation, measure of variation, spread, dispersion, deviation, divergence, range, interquartile range, total variation, absolute deviation, total deviation, statistics, duration, timing, trend, periodic characteristics, repetition characteristics, long-term characteristics, historical characteristics, average characteristics, current characteristics, past characteristics, future characteristics, predicted characteristics, location, distance, height, speed, direction, velocity, acceleration, change of the acceleration, angle, angular speed, angular velocity, angular acceleration of the object, change of the angular acceleration, orientation of the object, angular of rotation, deformation of the object, shape of the object, change of shape of the object, change of size of the object, change of structure of the object, and/or change of characteristics of the object. 
     At least one local maximum and at least one local minimum of the function may be identified. At least one local signal-to-noise-ratio-like (SNR-like) parameter may be computed for each pair of adjacent local maximum and local minimum. The SNR-like parameter may be a function (e.g. linear, log, exponential function, monotonic function) of a fraction of a quantity (e.g. power, magnitude) of the local maximum over the same quantity of the local minimum. It may also be the function of a difference between the quantity of the local maximum and the same quantity of the local minimum. Significant local peaks may be identified or selected. Each significant local peak may be a local maximum with SNR-like parameter greater than a threshold T1 and/or a local maximum with amplitude greater than a threshold T2. The at least one local minimum and the at least one local minimum in the frequency domain may be identified/computed using a persistence-based approach. 
     A set of selected significant local peaks may be selected from the set of identified significant local peaks based on a selection criterion (e.g. a quality criterion, a signal quality condition). The characteristics/STI of the object may be computed based on the set of selected significant local peaks and frequency values associated with the set of selected significant local peaks. In one example, the selection criterion may always correspond to select the strongest peaks in a range. While the strongest peaks may be selected, the unselected peaks may still be significant (rather strong). 
     Unselected significant peaks may be stored and/or monitored as “reserved” peaks for use in future selection in future sliding time windows. As an example, there may be a particular peak (at a particular frequency) appearing consistently over time. Initially, it may be significant but not selected (as other peaks may be stronger). But in later time, the peak may become stronger and more dominant and may be selected. When it became “selected”, it may be back-traced in time and made “selected” in the earlier time when it was significant but not selected. In such case, the back-traced peak may replace a previously selected peak in an early time. The replaced peak may be the relatively weakest, or a peak that appear in isolation in time (i.e. appearing only briefly in time). 
     In another example, the selection criterion may not correspond to select the strongest peaks in the range. Instead, it may consider not only the “strength” of the peak, but the “trace” of the peak—peaks that may have happened in the past, especially those peaks that have been identified for a long time. For example, if a finite state machine (FSM) is used, it may select the peak(s) based on the state of the FSM. Decision thresholds may be computed adaptively (and/or dynamically) based on the state of the FSM. 
     A similarity score and/or component similarity score may be computed (e.g. by a server (e.g. hub device), the processor, the Type 1 device, the Type 2 device, a local server, a cloud server, and/or another device) based on a pair of temporally adjacent CI of a TSCI. The pair may come from the same sliding window or two different sliding windows. The similarity score may also be based on a pair of, temporally adjacent or not so adjacent, CI from two different TSCI. The similarity score and/or component similar score may be/comprise: time reversal resonating strength (TRRS), correlation, cross-correlation, auto-correlation, correlation indicator, covariance, cross-covariance, auto-covariance, inner product of two vectors, distance score, norm, metric, quality metric, signal quality condition, statistical characteristics, discrimination score, neural network, deep learning network, machine learning, training, discrimination, weighted averaging, preprocessing, denoising, signal conditioning, filtering, time correction, timing compensation, phase offset compensation, transformation, component-wise operation, feature extraction, finite state machine, and/or another score. The characteristics and/or STI may be determined/computed based on the similarity score. 
     Any threshold may be pre-determined, adaptively (and/or dynamically) determined and/or determined by a finite state machine. The adaptive determination may be based on time, space, location, antenna, path, link, state, battery life, remaining battery life, available power, available computational resources, available network bandwidth, etc. 
     A threshold to be applied to a test statistics to differentiate two events (or two conditions, or two situations, or two states), A and B, may be determined. Data (e.g. CI, channel state information (CSI), power parameter) may be collected under A and/or under B in a training situation. The test statistics may be computed based on the data. Distributions of the test statistics under A may be compared with distributions of the test statistics under B (reference distribution), and the threshold may be chosen according to some criteria. The criteria may comprise: maximum likelihood (ML), maximum aposterior probability (MAP), discriminative training, minimum Type 1 error for a given Type 2 error, minimum Type 2 error for a given Type 1 error, and/or other criteria (e.g. a quality criterion, signal quality condition). The threshold may be adjusted to achieve different sensitivity to the A, B and/or another event/condition/situation/state. The threshold adjustment may be automatic, semi-automatic and/or manual. The threshold adjustment may be applied once, sometimes, often, periodically, repeatedly, occasionally, sporadically, and/or on demand. The threshold adjustment may be adaptive (and/or dynamically adjusted). The threshold adjustment may depend on the object, object movement/location/direction/action, object characteristics/STI/size/property/trait/habit/behavior, the venue, feature/fixture/furniture/barrier/material/machine/living thing/thing/object/boundary/surface/medium that is in/at/of the venue, map, constraint of the map (or environmental model), the event/state/situation/condition, time, timing, duration, current state, past history, user, and/or a personal preference, etc. 
     A stopping criterion (or skipping or bypassing or blocking or pausing or passing or rejecting criterion) of an iterative algorithm may be that change of a current parameter (e.g. offset value) in the updating in an iteration is less than a threshold. The threshold may be 0.5, 1, 1.5, 2, or another number. The threshold may be adaptive (and/or dynamically adjusted). It may change as the iteration progresses. For the offset value, the adaptive threshold may be determined based on the task, particular value of the first time, the current time offset value, the regression window, the regression analysis, the regression function, the regression error, the convexity of the regression function, and/or an iteration number. 
     The local extremum may be determined as the corresponding extremum of the regression function in the regression window. The local extremum may be determined based on a set of time offset values in the regression window and a set of associated regression function values. Each of the set of associated regression function values associated with the set of time offset values may be within a range from the corresponding extremum of the regression function in the regression window. 
     The searching for a local extremum may comprise robust search, minimization, maximization, optimization, statistical optimization, dual optimization, constraint optimization, convex optimization, global optimization, local optimization an energy minimization, linear regression, quadratic regression, higher order regression, linear programming, nonlinear programming, stochastic programming, combinatorial optimization, constraint programming, constraint satisfaction, calculus of variations, optimal control, dynamic programming, mathematical programming, multi-objective optimization, multi-modal optimization, disjunctive programming, space mapping, infinite-dimensional optimization, heuristics, metaheuristics, convex programming, semidefinite programming, conic programming, cone programming, integer programming, quadratic programming, fractional programming, numerical analysis, simplex algorithm, iterative method, gradient descent, subgradient method, coordinate descent, conjugate gradient method, Newton&#39;s algorithm, sequential quadratic programming, interior point method, ellipsoid method, reduced gradient method, quasi-Newton method, simultaneous perturbation stochastic approximation, interpolation method, pattern search method, line search, non-differentiable optimization, genetic algorithm, evolutionary algorithm, dynamic relaxation, hill climbing, particle swarm optimization, gravitation search algorithm, simulated annealing, memetic algorithm, differential evolution, dynamic relaxation, stochastic tunneling, Tabu search, reactive search optimization, curve fitting, least square, simulation based optimization, variational calculus, and/or variant. The search for local extremum may be associated with an objective function, loss function, cost function, utility function, fitness function, energy function, and/or an energy function. 
     Regression may be performed using regression function to fit sampled data (e.g. CI, feature of CI, component of CI) or another function (e.g. autocorrelation function) in a regression window. In at least one iteration, a length of the regression window and/or a location of the regression window may change. The regression function may be linear function, quadratic function, cubic function, polynomial function, and/or another function. The regression analysis may minimize at least one of: error, aggregate error, component error, error in projection domain, error in selected axes, error in selected orthogonal axes, absolute error, square error, absolute deviation, square deviation, higher order error (e.g. third order, fourth order), robust error (e.g. square error for smaller error magnitude and absolute error for larger error magnitude, or first kind of error for smaller error magnitude and second kind of error for larger error magnitude), another error, weighted sum (or weighted mean) of absolute/square error (e.g. for wireless transmitter with multiple antennas and wireless receiver with multiple antennas, each pair of transmitter antenna and receiver antenna form a link), mean absolute error, mean square error, mean absolute deviation, and/or mean square deviation. Error associated with different links may have different weights. One possibility is that some links and/or some components with larger noise or lower signal quality metric may have smaller or bigger weight), weighted sum of square error, weighted sum of higher order error, weighted sum of robust error, weighted sum of the another error, absolute cost, square cost, higher order cost, robust cost, another cost, weighted sum of absolute cost, weighted sum of square cost, weighted sum of higher order cost, weighted sum of robust cost, and/or weighted sum of another cost. The regression error determined may be an absolute error, square error, higher order error, robust error, yet another error, weighted sum of absolute error, weighted sum of square error, weighted sum of higher order error, weighted sum of robust error, and/or weighted sum of the yet another error. 
     The time offset associated with maximum regression error (or minimum regression error) of the regression function with respect to the particular function in the regression window may become the updated current time offset in the iteration. 
     A local extremum may be searched based on a quantity comprising a difference of two different errors (e.g. a difference between absolute error and square error). Each of the two different errors may comprise an absolute error, square error, higher order error, robust error, another error, weighted sum of absolute error, weighted sum of square error, weighted sum of higher order error, weighted sum of robust error, and/or weighted sum of the another error. 
     The quantity may be compared with a reference data or a reference distribution, such as an F-distribution, central F-distribution, another statistical distribution, threshold, threshold associated with probability/histogram, threshold associated with probability/histogram of finding false peak, threshold associated with the F-distribution, threshold associated the central F-distribution, and/or threshold associated with the another statistical distribution. 
     The regression window may be determined based on at least one of: the movement (e.g. change in position/location) of the object, quantity associated with the object, the at least one characteristics and/or STI of the object associated with the movement of the object, estimated location of the local extremum, noise characteristics, estimated noise characteristics, signal quality metric, F-distribution, central F-distribution, another statistical distribution, threshold, preset threshold, threshold associated with probability/histogram, threshold associated with desired probability, threshold associated with probability of finding false peak, threshold associated with the F-distribution, threshold associated the central F-distribution, threshold associated with the another statistical distribution, condition that quantity at the window center is largest within the regression window, condition that the quantity at the window center is largest within the regression window, condition that there is only one of the local extremum of the particular function for the particular value of the first time in the regression window, another regression window, and/or another condition. 
     The width of the regression window may be determined based on the particular local extremum to be searched. The local extremum may comprise first local maximum, second local maximum, higher order local maximum, first local maximum with positive time offset value, second local maximum with positive time offset value, higher local maximum with positive time offset value, first local maximum with negative time offset value, second local maximum with negative time offset value, higher local maximum with negative time offset value, first local minimum, second local minimum, higher local minimum, first local minimum with positive time offset value, second local minimum with positive time offset value, higher local minimum with positive time offset value, first local minimum with negative time offset value, second local minimum with negative time offset value, higher local minimum with negative time offset value, first local extremum, second local extremum, higher local extremum, first local extremum with positive time offset value, second local extremum with positive time offset value, higher local extremum with positive time offset value, first local extremum with negative time offset value, second local extremum with negative time offset value, and/or higher local extremum with negative time offset value. 
     A current parameter (e.g. time offset value) may be initialized based on a target value, target profile, trend, past trend, current trend, target speed, speed profile, target speed profile, past speed trend, the motion or movement (e.g. change in position/location) of the object, at least one characteristics and/or STI of the object associated with the movement of object, positional quantity of the object, initial speed of the object associated with the movement of the object, predefined value, initial width of the regression window, time duration, value based on carrier frequency of the signal, value based on subcarrier frequency of the signal, bandwidth of the signal, amount of antennas associated with the channel, noise characteristics, signal h metric, and/or an adaptive (and/or dynamically adjusted) value. The current time offset may be at the center, on the left side, on the right side, and/or at another fixed relative location, of the regression window. 
     In the presentation, information may be displayed with a map (or environmental model) of the venue. The information may comprise: location, zone, region, area, coverage area, corrected location, approximate location, location with respect to (w.r.t.) a map of the venue, location w.r.t. a segmentation of the venue, direction, path, path w.r.t. the map and/or the segmentation, trace (e.g. location within a time window such as the past 5 seconds, or past 10 seconds; the time window duration may be adjusted adaptively (and/or dynamically); the time window duration may be adaptively (and/or dynamically) adjusted w.r.t. speed, acceleration, etc.), history of a path, approximate regions/zones along a path, history/summary of past locations, history of past locations of interest, frequently-visited areas, customer traffic, crowd distribution, crowd behavior, crowd control information, speed, acceleration, motion statistics, breathing rate, heart rate, presence/absence of motion, presence/absence of people or pets or object, presence/absence of vital sign, gesture, gesture control (control of devices using gesture), location-based gesture control, information of a location-based operation, identity (ID) or identifier of the respect object (e.g. pet, person, self-guided machine/device, vehicle, drone, car, boat, bicycle, self-guided vehicle, machine with fan, air-conditioner, TV, machine with movable part), identification of a user (e.g. person), information of the user, location/speed/acceleration/direction/motion/gesture/gesture control/motion trace of the user, ID or identifier of the user, activity of the user, state of the user, sleeping/resting characteristics of the user, emotional state of the user, vital sign of the user, environment information of the venue, weather information of the venue, earthquake, explosion, storm, rain, fire, temperature, collision, impact, vibration, event, door-open event, door-close event, window-open event, window-close event, fall-down event, burning event, freezing event, water-related event, wind-related event, air-movement event, accident event, pseudo-periodic event (e.g. running on treadmill, jumping up and down, skipping rope, somersault, etc.), repeated event, crowd event, vehicle event, gesture of the user (e.g. hand gesture, arm gesture, foot gesture, leg gesture, body gesture, head gesture, face gesture, mouth gesture, eye gesture, etc.). The location may be 2-dimensional (e.g. with 2D coordinates), 3-dimensional (e.g. with 3D coordinates). The location may be relative (e.g. w.r.t. a map or environmental model) or relational (e.g. halfway between point A and point B, around a corner, up the stairs, on top of table, at the ceiling, on the floor, on a sofa, close to point A, a distance R from point A, within a radius of R from point A, etc.). The location may be expressed in rectangular coordinate, polar coordinate, and/or another representation. 
     The information (e.g. location) may be marked with at least one symbol. The symbol may be time varying. The symbol may be flashing and/or pulsating with or without changing color/intensity. The size may change over time. The orientation of the symbol may change over time. The symbol may be a number that reflects an instantaneous quantity (e.g. vital sign/breathing rate/heart rate/gesture/state/status/action/motion of a user, temperature, network traffic, network connectivity, status of a device/machine, remaining power of a device, status of the device, etc.). The rate of change, the size, the orientation, the color, the intensity and/or the symbol may reflect the respective motion. The information may be disclosed visually and/or described verbally (e.g. using pre-recorded voice, or voice synthesis). The information may be described in text. The information may also be disclosed in a mechanical way (e.g. an animated gadget, a movement of a movable part). 
     The user-interface (UI) device may be a smart phone (e.g. iPhone, Android phone), tablet (e.g. iPad), laptop (e.g. notebook computer), personal computer (PC), device with graphical user interface (GUI), smart speaker, device with voice/audio/speaker capability, virtual reality (VR) device, augmented reality (AR) device, smart car, display in the car, voice assistant, voice assistant in a car, etc. The map (or environmental model) may be 2-dimensional, 3-dimensional and/or higher-dimensional. (e.g. a time varying 2D/3D map/environmental model) Walls, windows, doors, entrances, exits, forbidden areas may be marked on the map or the model. The map may comprise floor plan of a facility. The map or model may have one or more layers (overlays). The map/model may be a maintenance map/model comprising water pipes, gas pipes, wiring, cabling, air ducts, crawl-space, ceiling layout, and/or underground layout. The venue may be segmented/subdivided/zoned/grouped into multiple zones/regions/geographic regions/sectors/sections/territories/districts/precincts/localities/neighborhoods/areas/stretches/expanse such as bedroom, living room, storage room, walkway, kitchen, dining room, foyer, garage, first floor, second floor, rest room, offices, conference room, reception area, various office areas, various warehouse regions, various facility areas, etc. The segments/regions/areas may be disclosed in a map/model. Different regions may be color-coded. Different regions may be disclosed with a characteristic (e.g. color, brightness, color intensity, texture, animation, flashing, flashing rate, etc.). Logical segmentation of the venue may be done using the at least one heterogeneous Type 2 device, or a server (e.g. hub device), or a cloud server, etc. 
     Here is an example of the disclosed system, apparatus, and method. Stephen and his family want to install the disclosed wireless motion detection system to detect motion in their 2000 sqft two-storey town house in Seattle, Wash. Because his house has two storeys, Stephen decided to use one Type 2 device (named A) and two Type 1 devices (named B and C) in the ground floor. His ground floor has predominantly three rooms: kitchen, dining room and living room arranged in a straight line, with the dining room in the middle. The kitchen and the living rooms are on opposite end of the house. He put the Type 2 device (A) in the dining room, and put one Type 1 device (B) in the kitchen and the other Type 1 device (C) in the living room. With this placement of the devices, he is practically partitioning the ground floor into 3 zones (dining room, living room and kitchen) using the motion detection system. When motion is detected by the AB pair and the AC pair, the system would analyze the motion information and associate the motion with one of the 3 zones. 
     When Stephen and his family go out on weekends (e.g. to go for a camp during a long weekend), Stephen would use a mobile phone app (e.g. Android phone app or iPhone app) to turn on the motion detection system. When the system detects motion, a warning signal is sent to Stephen (e.g. an SMS text message, an email, a push message to the mobile phone app, etc.). If Stephen pays a monthly fee (e.g. $10/month), a service company (e.g. security company) will receive the warning signal through wired network (e.g. broadband) or wireless network (e.g. home WiFi, LTE, 3G, 2.5G, etc.) and perform a security procedure for Stephen (e.g. call him to verify any problem, send someone to check on the house, contact the police on behalf of Stephen, etc.). Stephen loves his aging mother and cares about her well-being when she is alone in the house. When the mother is alone in the house while the rest of the family is out (e.g. go to work, or shopping, or go on vacation), Stephen would turn on the motion detection system using his mobile app to ensure the mother is ok. He then uses the mobile app to monitor his mother&#39;s movement in the house. When Stephen uses the mobile app to see that the mother is moving around the house among the 3 regions, according to her daily routine, Stephen knows that his mother is doing ok. Stephen is thankful that the motion detection system can help him monitor his mother&#39;s well-being while he is away from the house. 
     On a typical day, the mother would wake up at around 7 AM. She would cook her breakfast in the kitchen for about 20 minutes. Then she would eat the breakfast in the dining room for about 30 minutes. Then she would do her daily exercise in the living room, before sitting down on the sofa in the living room to watch her favorite TV show. The motion detection system enables Stephen to see the timing of the movement in each of the 3 regions of the house. When the motion agrees with the daily routine, Stephen knows roughly that the mother should be doing fine. But when the motion pattern appears abnormal (e.g. there is no motion until 10 AM, or she stayed in the kitchen for too long, or she remains motionless for too long, etc.), Stephen suspects something is wrong and would call the mother to check on her. Stephen may even get someone (e.g. a family member, a neighbor, a paid personnel, a friend, a social worker, a service provider) to check on his mother. 
     At some time, Stephen feels like repositioning the Type 2 device. He simply unplugs the device from the original AC power plug and plug it into another AC power plug. He is happy that the wireless motion detection system is plug-and-play and the repositioning does not affect the operation of the system. Upon powering up, it works right away. Sometime later, Stephen is convinced that the disclosed wireless motion detection system can really detect motion with very high accuracy and very low alarm, and he really can use the mobile app to monitor the motion in the ground floor. He decides to install a similar setup (i.e. one Type 2 device and two Type 1 devices) in the second floor to monitor the bedrooms in the second floor. Once again, he finds that the system set up is extremely easy as he simply needs to plug the Type 2 device and the Type 1 devices into the AC power plug in the second floor. No special installation is needed. And he can use the same mobile app to monitor motion in the ground floor and the second floor. Each Type 2 device in the ground floor/second floor can interact with all the Type 1 devices in both the ground floor and the second floor. Stephen is happy to see that, as he doubles his investment in the Type 1 and Type 2 devices, he has more than double the capability of the combined systems. 
     According to various embodiments, each CI (CI) may comprise at least one of: channel state information (CSI), frequency domain CSI, frequency representation of CSI, frequency domain CSI associated with at least one sub-band, time domain CSI, CSI in domain, channel response, estimated channel response, channel impulse response (CIR), channel frequency response (CFR), channel characteristics, channel filter response, CSI of the wireless multipath channel, information of the wireless multipath channel, timestamp, auxiliary information, data, meta data, user data, account data, access data, security data, session data, status data, supervisory data, household data, identity (ID), identifier, device data, network data, neighborhood data, environment data, real-time data, sensor data, stored data, encrypted data, compressed data, protected data, and/or another CI. In one embodiment, the disclosed system has hardware components (e.g. wireless transmitter/receiver with antenna, analog circuitry, power supply, processor, memory) and corresponding software components. According to various embodiments of the present teaching, the disclosed system includes Bot (referred to as a Type 1 device) and Origin (referred to as a Type 2 device) for vital sign detection and monitoring. Each device comprises a transceiver, a processor and a memory. 
     The disclosed system can be applied in many cases. In one example, the Type 1 device (transmitter) may be a small WiFi-enabled device resting on the table. It may also be a WiFi-enabled television (TV), set-top box (STB), a smart speaker (e.g. Amazon echo), a smart refrigerator, a smart microwave oven, a mesh network router, a mesh network satellite, a smart phone, a computer, a tablet, a smart plug, etc. In one example, the Type 2 (receiver) may be a WiFi-enabled device resting on the table. It may also be a WiFi-enabled television (TV), set-top box (STB), a smart speaker (e.g. Amazon echo), a smart refrigerator, a smart microwave oven, a mesh network router, a mesh network satellite, a smart phone, a computer, a tablet, a smart plug, etc. The Type 1 device and Type 2 devices may be placed in/near a conference room to count people. The Type 1 device and Type 2 devices may be in a well-being monitoring system for older adults to monitor their daily activities and any sign of symptoms (e.g. dementia, Alzheimer&#39;s disease). The Type 1 device and Type 2 device may be used in baby monitors to monitor the vital signs (breathing) of a living baby. The Type 1 device and Type 2 devices may be placed in bedrooms to monitor quality of sleep and any sleep apnea. The Type 1 device and Type 2 devices may be placed in cars to monitor well-being of passengers and driver, detect any sleeping of driver and detect any babies left in a car. The Type 1 device and Type 2 devices may be used in logistics to prevent human trafficking by monitoring any human hidden in trucks and containers. The Type 1 device and Type 2 devices may be deployed by emergency service at disaster area to search for trapped victims in debris. The Type 1 device and Type 2 devices may be deployed in an area to detect breathing of any intruders. There are numerous applications of wireless breathing monitoring without wearables. 
     Hardware modules may be constructed to contain the Type 1 transceiver and/or the Type 2 transceiver. The hardware modules may be sold to/used by variable brands to design, build and sell final commercial products. Products using the disclosed system and/or method may be home/office security products, sleep monitoring products, WiFi products, mesh products, TV, STB, entertainment system, HiFi, speaker, home appliance, lamps, stoves, oven, microwave oven, table, chair, bed, shelves, tools, utensils, torches, vacuum cleaner, smoke detector, sofa, piano, fan, door, window, door/window handle, locks, smoke detectors, car accessories, computing devices, office devices, air conditioner, heater, pipes, connectors, surveillance camera, access point, computing devices, mobile devices, LTE devices, 3G/4G/5G/6G devices, UMTS devices, 3GPP devices, GSM devices, EDGE devices, TDMA devices, FDMA devices, CDMA devices, WCDMA devices, TD-SCDMA devices, gaming devices, eyeglasses, glass panels, VR goggles, necklace, watch, waist band, belt, wallet, pen, hat, wearables, implantable device, tags, parking tickets, smart phones, etc. 
     The summary may comprise: analytics, output response, selected time window, subsampling, transform, and/or projection. The presenting may comprise presenting at least one of: monthly/weekly/daily view, simplified/detailed view, cross-sectional view, small/large form-factor view, color-coded view, comparative view, summary view, animation, web view, voice announcement, and another presentation related to the periodic/repetition characteristics of the repeating motion. 
     A Type 1/Type 2 device may be an antenna, a device with antenna, a device with a housing (e.g. for radio, antenna, data/signal processing unit, wireless IC, circuits), device that has interface to attach/connect to/link antenna, device that is interfaced to/attached to/connected to/linked to another device/system/computer/phone/network/data aggregator, device with a user interface (UI)/graphical UI/display, device with wireless transceiver, device with wireless transmitter, device with wireless receiver, internet-of-thing (IoT) device, device with wireless network, device with both wired networking and wireless networking capability, device with wireless integrated circuit (IC), Wi-Fi device, device with Wi-Fi chip (e.g. 802.11a/b/g/n/ac/ax standard compliant), Wi-Fi access point (AP), Wi-Fi client, Wi-Fi router, Wi-Fi repeater, Wi-Fi hub, Wi-Fi mesh network router/hub/AP, wireless mesh network router, adhoc network device, wireless mesh network device, mobile device (e.g. 2G/2.5G/3G/3.5G/4G/LTE/5G/6G/7G, UMTS, 3GPP, GSM, EDGE, TDMA, FDMA, CDMA, WCDMA, TD-SCDMA), cellular device, base station, mobile network base station, mobile network hub, mobile network compatible device, LTE device, device with LTE module, mobile module (e.g. circuit board with mobile-enabling chip (IC) such as Wi-Fi chip, LTE chip, BLE chip), Wi-Fi chip (IC), LTE chip, BLE chip, device with mobile module, smart phone, companion device (e.g. dongle, attachment, plugin) for smart phones, dedicated device, plug-in device, AC-powered device, battery-powered device, device with processor/memory/set of instructions, smart device/gadget/items: clock, stationary, pen, user-interface, paper, mat, camera, television (TV), set-top-box, microphone, speaker, refrigerator, oven, machine, phone, wallet, furniture, door, window, ceiling, floor, wall, table, chair, bed, night-stand, air-conditioner, heater, pipe, duct, cable, carpet, decoration, gadget, USB device, plug, dongle, lamp/light, tile, ornament, bottle, vehicle, car, AGV, drone, robot, laptop, tablet, computer, harddisk, network card, instrument, racket, ball, shoe, wearable, clothing, glasses, hat, necklace, food, pill, small device that moves in the body of creature (e.g. in blood vessels, in lymph fluid, digestive system), and/or another device. The Type 1 device and/or Type 2 device may be communicatively coupled with: the internet, another device with access to internet (e.g. smart phone), cloud server (e.g. hub device), edge server, local server, and/or storage. The Type 1 device and/or the Type 2 device may operate with local control, can be controlled by another device via a wired/wireless connection, can operate automatically, or can be controlled by a central system that is remote (e.g. away from home). 
     In one embodiment, a Type B device may be a transceiver that may perform as both Origin (a Type 2 device, a Rx device) and Bot (a Type 1 device, a Tx device), i.e., a Type B device may be both Type 1 (Tx) and Type 2 (Rx) devices (e.g. simultaneously or alternately), for example, mesh devices, a mesh router, etc. In one embodiment, a Type A device may be a transceiver that may only function as Bot (a Tx device), i.e., Type 1 device only or Tx only, e.g., simple IoT devices. It may have the capability of Origin (Type 2 device, Rx device), but somehow it is functioning only as Bot in the embodiment. All the Type A and Type B devices form a tree structure. The root may be a Type B device with network (e.g. internet) access. For example, it may be connected to broadband service through a wired connection (e.g. Ethernet, cable modem, ADSL/HDSL modem) connection or a wireless connection (e.g. LTE, 3G/4G/5G, WiFi, Bluetooth, microwave link, satellite link, etc.). In one embodiment, all the Type A devices are leaf node. Each Type B device may be the root node, non-leaf node, or leaf node. 
     Wireless detection of respiration rates is crucial for many applications. Most of the state-of-art solutions estimate breathing rates with the prior knowledge of crowd numbers as well as assuming the distinct breathing rates of different users, which is neither natural nor realistic. However, few of them can leverage the estimated breathing rates to recognize human subjects (a.k.a, identity matching). In this disclosure, using the channel state information (CSI) of a single pair of commercial WiFi devices, a novel system is disclosed to continuously track the breathing rates of multiple persons without such impractical assumptions. The disclosed solution includes an adaptive subcarrier combination method that boosts the signal to noise ratio (SNR) of breathing signals, and an iterative dynamic programming and a trace concatenating algorithm that continuously track the breathing rates of multiple users. By leveraging both the spectrum and time diversity of the CSI, the disclosed system can correctly extract the breathing rate traces even if some of them merge together for a short time period. Furthermore, by utilizing the breathing traces obtained, the disclosed system can do people counting and recognition simultaneously. Extensive experiments are conducted in two environments (an on-campus lab and a car). The results show that 86% of average accuracy can be achieved for people counting up to 4 people for both cases. For 97.9% out of all the testing cases, the absolute error of crowd number estimates is within 1. The system achieves an average accuracy of 85.78% for people recognition in a smart home case. 
     In this disclosure, the disclosed solution can continuously track human respiration rate without any prior knowledge of the crowd number or assuming that the breathing rates of different users are distinct. The disclosed system focuses on matching the breathing rates estimated in different time instances to different users, i.e., which breathing rate corresponds to which person. By utilizing the estimated breathing rate traces, the disclosed system can achieve people counting as well as recognition at the same time. Achieving identity matching based on multi-person breathing rates for both purposes, however, entails several unique challenges. 
     First, the subtle changes caused by human breathing could be easily undermined by measurement noises in WiFi CSI. The situation becomes even worse in multi-person scenarios. To overcome the problem, one can leverage the diversity residing in subcarriers and multiple links (antenna pairs) to reduce noises while boosting the breathing signals. One can show that, by properly combining different subcarriers and links, the breathing signals can be considerably better enhanced than what could be achieved by any individual or the average of them. 
     Second, a person&#39;s breathing rate varies over time, making it non-trivial to associate the successive breathing rate estimates to the corresponding persons. Considering that one&#39;s breathing rate will not fluctuate within a short time period, one can build a Markov chain model for the natural breathing signals and further employ an iterative dynamic programming algorithm to continuously track multiple breathing traces (i.e., sequences of breathing rates of different users). 
     Third, the number of users may not be fixed for an area of interest, since users might come and go. In order to output real-time estimates of the occupancy level, the present teaching discloses a trace concatenating algorithm to maintain the traces of existing users, which concatenates the latest estimates with the disclosed traces to determine existing users, newly arriving users, and leaving users. 
     Lastly, although the human respiration rate varies in a small range, breathing pattern of different individuals are distinct. Based on this observation, one can build a database of breathing traces and apply hypothesis-testing to do human recognition for the smart home scenario. 
     One can prototype the disclosed system using a pair of commodity off-the-shelf (COTS) WiFi devices and conduct experiments in two typical targeted environments (i.e., a lab office and a car), where 12 users are involved in the evaluation. The average accuracy of people counting up to 4 people is more than 86% for both environments. For 97.9% out of all the testing cases, the absolute error of crowd number estimates is within 1. The disclosed system achieves similar performance for both environments, demonstrating the independence on environment, which outperforms the training based method. Lastly, one can investigate the performance of people recognition using breathing traces for a 4-people family. The system can achieve 85.78% accuracy. The disclosed approach makes an important step towards smart home applications in terms of breathing rate estimation, passive people counting and human recognition. 
     The main contributions of this work are as follows. One can devise a pipeline of novel techniques to estimate the breathing traces of multiple users, including a subcarrier combination method to enhance multiple breathing signals, an iterative dynamic programming and trace concatenating algorithms to continuously track successive breathing rates of multiple users using the CSI of COTS WiFi devices. A non-intrusive training-free method is disclosed to estimate the crowd number using the extracted breathing traces. Furthermore, a hypothesis-testing model is disclosed to leverage the breathing traces to do human recognition. One can prototype and evaluate the disclosed system on COTS WiFi devices. The results in indoor spaces and in a car demonstrate promising performance. 
     The computational pipeline underlying the disclosed system is shown in  FIG. 1 . Different from many previous works aiming at estimating independent breathing rates at certain time instances, this work focuses on utilizing the frequency as well as time domain information to do identity matching. The core idea is to estimate the breathing rate sequences along the time (a.k.a, breathing rate traces) of different individuals. Furthermore, utilizing the estimated breathing traces, one can estimate the occupancy level as well as predict the user identity in the observation area. This idea immediately leads to three stages of the disclosed system: (1) Multi-user breathing spectrum generation, (2) breathing rate trace tracking, and (3) people counting and recognition. 
     In the first stage, the disclosed system first performs Short-Term Fourier Transform (STFT) on CSI measurements to extract the periodic breathing signals. As long as the breathing rates of different individuals are different, multiple frequency components would be observed in the frequency response. The extracted breathing signals are typically fairly weak on a single subcarrier, which are further boosted by a novel adaptive subcarrier combining method. Stage 1 finally outputs a spectrogram of the estimated breathing rates over time. 
     In Stage 2, the goal is to track the breathing rate traces (i.e., breathing sources) from the spectragram obtained from Stage 1. However, there is a significant gap between breathing rates to breathing rate traces because of two reasons: First, different individuals may have the same breathing rates that overlap with each other. Second, one&#39;s breathing rate varies over time. To address the challenges, a Markov Chain Model is introduced to handle dynamics in natural breathing. The present teaching discloses a successive cancellation scheme that resolves each individual&#39;s breathing trace one by one by a novel algorithm of iterative dynamic programming. Thereafter, one can concatenate the identified traces of breathing rates in adjacent time windows to further identify the arriving and leaving time of human subjects. 
     In Stage 3, one can leverage the estimated breathing rate traces given by Stage 2 to do people counting and recognition. By further utilizing the time-domain information and removing outliers of the estimated breathing rate traces by a novel quasi-bilateral filter, the system gives an estimate of the crowd number. Then by hypothesis testing, one can do people identity recognition according to the extracted breathing rate traces. 
     Multi-User Breathing Spectrum Generation 
     CSI Model with Breathing Impact 
     The channel state information (CSI) depicts how radio signals propagate from a transmitter (Tx) to a receiver (Rx). In the presence of human beings, one or more paths of signal propagation will be altered due to human motion. Given a pair of Tx and Rx with multiple omnidirectional antennas, the CSI of link m at time t and frequency ƒ k  is modeled as 
     
       
         
           
             
               
                 
                   
                     
                       
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     where k∈  is the subcarrier (SC) index with center frequency ƒ k  in the set of usable SCs  . L is the total number of multipath components (MPCs), while a l (t) and d l (t) denote the complex gain and propagation length of MPC l. n(t, ƒ k ) is the additive white noise, and c is the speed of light. 
     In the presence of breathing, (1) can be rewritten as 
     
       
         
           
             
               
                 
                   
                     
                       
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     where   denotes the set of human subjects. Ω d     i    denotes the MPCs scattered by human being i, resulting in time-variant complex gain and delay, Ω s  denotes the MPCs that are not affected by people&#39;s breathing, whose complex gain and delay keep time-invariant. The gain of MPCs in Ω d     i    could be modeled as 
     
       
         
           
             
               
                 
                   
                     
                       
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     where a l  and d l  are gain and path length in a static environment, Δd l  is the difference of propagation length caused by chest movement, θ is the angle between human scatter and the EM wave, and ϕ is the initial phase. Ψ is the path loss exponent. Since the chest movement is much smaller than the path length, i.e., Δd l &lt;&lt;d l , the amplitude of MPC in both Ω s  and Ω d     i    can be assumed to be time-invariant, e.g., a l (t)≈a l , and the set of MPCs are assumed to be the same, i.e., Ω d     i   (t)≈Ω d     i   . 
     Boosting SNR of Breathing Signals 
     For each MPC subset Ω d     i   , the delay is periodic due to the periodic chest movement, i.e., d l (t+T b     i   )=d l (t), ∀l∈Ω d     i   . Hence one would be able to see multiple frequency components of the measured CSI in frequency domain, each corresponding to a distinct breathing signal. 
     The breathing signals can be extracted by applying Short-Term Fourier Transform (STFT) to the CSI measurement. In specific, one can first apply a sliding window of length W to the captured CSI time series of each SC in every link, and then obtain the frequency spectrum by performing Fast Fourier Transform (FFT) over each time window. One can then employ a bandpass filter on the spectrum to consider only the normal range of human breathing frequencies [b min , b max ]. The FFT is performed on every SC to obtain the individual spectrum for all the N Tx ×N Rx ×N sc  SCs, where N Tx , N Rx , and N sc  are the number of Tx antennas, Rx antennas, and usable SCs on each Tx-Rx link, respectively. 
     As shown in  FIG. 2 , each breathing signal from one person contributes to one evident peak in the obtained power spectrum density (PSD). Different SCs experience diverse sensitivity levels to the identical breathing motion. Previous approaches attempt to select a set of best SCs based on variance, amplitude or ensemble average of CSI among all SCs to improve SNR. However, the following observations show the flaws of these approaches: 1) The response power of different SCs to the same breathing source is different (See columns in  FIG. 2 ). 2) For the same SC, the response power to different breathing sources is different (See rows in  FIG. 2 ). 3) The response power of different links is distinct (Different figures in  FIG. 2 ). Therefore, there is no single SC that is universally sensitive to all breathing sources. Using the same subset of SCs for different frequency components may not produce equally good SNR for all breathing signals. Furthermore, using a universal threshold for all links may lose information from links with low response power. 
     Inspired by these observations, one can first use a novel adaptive SC combining criteria to boost the SNR of breathing signal of each link. For link m, the selected SCs for a given frequency component q satisfy the condition that 
     
       
         
           
             
               
                 
                   
                     
                       
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                                 ( 
                                 m 
                                 ) 
                               
                             
                              
                             
                               ( 
                               
                                 q 
                                 , 
                                 i 
                               
                               ) 
                             
                           
                           } 
                         
                       
                     
                   
                   , 
                   
                     ∀ 
                     
                       k 
                       ∈ 
                       V 
                     
                   
                   , 
                 
               
               
                 
                   ( 
                   4 
                   ) 
                 
               
             
           
         
       
     
     where Q is the set of frequency components in the range of [b min , b max ]. E k   (m) (q) denotes the power of the k-th SC over link m at frequency component q and  {E (m) (q, i)} denotes the maximum power of link m over all frequency components and SCs. α is a hyper-parameter which determines a relative threshold th (m) = {E (m) (q, i)} for SC selection. Note that th (m)  is adaptive to individual link quality, as inspired by the third observation above. Thus, the enhanced power of frequency component q in link m is 
         E   (m) ( q )←   E   k   (m) ( q )1( E   k   (m) ( q )≥ th   (m) ).  (5)
 
     To further incorporate diverse link quality, one can normalize the power for each link and then combine them together to further improve the SNR: 
                         E     (   m   )            (   q   )       ←         E     (   m   )            (   q   )           ∑     i   ∈   Q              E     (   m   )            (   i   )             ,     ∀     q   ∈   Q       ,           (   6   )                 E ( q )←Σ m=1   M   E   (m) ( q ),∀ q∈Q,   (7)
 
     where E(q) is the power of frequency component q after link combination and M=N Tx ×N Rx  is the total number of links. 
       FIG. 3  shows the effect of SC combination for several exemplary links. As seen, the disclosed SC selection and combination scheme (shown in blue curves) remarkably improves the SNR for the frequency components of interests, outperforming the simple average scheme (shown in red curves).  FIG. 4  further depicts the PSD after the combination of all 9 links, which demonstrates that noise and interference have been effectively suppressed. The ground-truth of breathing rates are marked with the black dashed lines. As a comparison, simple average of all SCs suffer from less dominant peaks for the desired breathing signals and false peaks. 
     Breathing Rate Trace Tracking 
     From Breathing Rates to Breathing Rate Traces 
     Previous works estimate the number of people by the number of candidate breathing rates. However, they have several limitations. First, the breathing rate estimation may not be accurate enough for a single time instance. Second, different users may have close breathing rates that are indistinguishable from the frequency spectrum, resulting in potential underestimation. Third, the number of people could vary over time as people may come and go. And the accompanying motion will also corrupt the breathing signals. 
     To map the breathing rates to individuals and thus further estimate the accurate crowd number, one can utilize the diversity in the time series of breathing rate estimates for reliable estimation. One can first model the dynamic breathing rates as a Markov process. Noting that the breathing signals are periodic where breathing frequency can smoothly change over time, the variation of breathing rate between two adjacent time bins is assumed to follow a normal distribution  (0, σ 2 ), with the probability density function (PDF) p(ƒ). Since the operation of STFT automatically discretizes the continuous frequency in the range of [b min , b max ] into |Q| frequency components, where |Q| means the cardinality of set Q, the natural beath can be modeled as a Markov chain, and the transition probability matrix is denoted as P∈   |Q| ×   |Q| , which is defined as 
     
       
         
           
             
               
                 
                   
                     
                       
                         
                           P 
                            
                           
                             ( 
                             
                               q 
                               , 
                               
                                 q 
                                 ′ 
                               
                             
                             ) 
                           
                         
                         = 
                           
                          
                         
                           P 
                            
                           
                             ( 
                             
                               
                                 g 
                                  
                                 
                                   ( 
                                   i 
                                   ) 
                                 
                               
                               = 
                               
                                 
                                   
                                     q 
                                     ′ 
                                   
                                   | 
                                   
                                     g 
                                      
                                     
                                       ( 
                                       
                                         i 
                                         - 
                                         1 
                                       
                                       ) 
                                     
                                   
                                 
                                 = 
                                 q 
                               
                             
                             ) 
                           
                         
                       
                     
                   
                   
                     
                       
                         
                           = 
                             
                            
                           
                             
                               
                                 ∫ 
                                 
                                   
                                     ( 
                                     
                                       
                                         q 
                                         ′ 
                                       
                                       - 
                                       q 
                                       - 
                                       
                                         1 
                                         2 
                                       
                                     
                                     ) 
                                   
                                   * 
                                   Δ 
                                    
                                   
                                       
                                   
                                    
                                   f 
                                 
                               
                               
                                 
                                   ( 
                                   
                                     
                                       q 
                                       ′ 
                                     
                                     - 
                                     q 
                                     + 
                                     
                                       1 
                                       2 
                                     
                                   
                                   ) 
                                 
                                 * 
                                 Δ 
                                  
                                 
                                     
                                 
                                  
                                 f 
                               
                             
                              
                             
                               
                                 p 
                                  
                                 
                                   ( 
                                   f 
                                   ) 
                                 
                               
                                
                               df 
                             
                           
                         
                         , 
                       
                     
                   
                 
               
               
                 
                   ( 
                   8 
                   ) 
                 
               
             
           
         
       
     
     where ∀q, q′∈Q and g is a mapping indicating the frequency component of the breathing rate at given time slots. 
     To estimate the breathing rate trace in a given time slot t, the disclosed system leverages the spectrum in [t−W, t], where W is the window length. An output is produced every W s  seconds, and the spectrum is updated at the same time. Thus to estimate the breathing traces at time t, a spectrum S∈   +   I ×   +   |Q|  is leveraged, where 
     
       
         
           
             
               I 
               = 
               
                 W 
                 
                   W 
                   s 
                 
               
             
             . 
           
         
       
     
     In principle, the breathing signal is more periodic than noise and other motion interference. Thus, it is more likely to be observed as peaks in most of the time, and thus the breathing signal will form a trace in the given spectrum along the time with the frequency changing slightly, as shown in  FIG. 5 . In the following, one can first extract the traces of successive breathing rates in the given window, and then concatenate them over time. 
     Extracting Breathing Rate Traces 
     Theoretical Model 
     For a given spectrum S, a reasonable estimate of the breathing trace can be obtained by 
     
       
         
           
             
               
                 
                   
                     
                       g 
                       * 
                     
                     = 
                     
                       
                         argmax 
                         g 
                       
                        
                       
                         E 
                          
                         
                           ( 
                           g 
                           ) 
                         
                       
                     
                   
                   , 
                 
               
               
                 
                   ( 
                   9 
                   ) 
                 
               
             
           
         
       
     
     where g indicates the breathing trace, denoted as 
         g =( g ( n ), n ) n=1   I .  (10)
 
     Here, g:[1,I]→Q is a mapping indicating the frequency component of the trace at the given time. E(g) is the power of a trace, defined as 
         E ( g )=Σ i=1   I   S ( i,g ( i )),  (11)
 
     where S(i,j) denotes the power at time bin i and frequency component j. 
     Considering that one&#39;s breathing rate will not fluctuate a lot within a short period, a regularization term is added to penalize sudden changes in frequencies of interests. A breathing trace is then a series of breathing rate estimates that achieve a good balance between frequency power and temporal smoothness. The smoothness of a trace can be evaluated by a cost function C(g), defined as 
         C ( g ) −log  P ( g (1))−Σ i=2   I  log  P ( g ( i− 1), g ( i )),  (12)
 
     where the frequency transition probability P(g(i−1), g(i)) can be calculated by (8). Without loss of generality, one can assume a uniform prior distribution, i.e., 
     
       
         
           
             
               
                 P 
                  
                 
                   ( 
                   
                     g 
                      
                     
                       ( 
                       1 
                       ) 
                     
                   
                   ) 
                 
               
               = 
               
                 1 
                 
                    
                   Q 
                    
                 
               
             
             . 
           
         
       
     
     The cost function C(g) is the negative of the log-likelihood for a given trace. The smoother a trace is, the larger its probability is, and the smaller the cost it incurs. 
     The most probable breathing trace can be found by solving 
     
       
         
           
             
               
                 
                   
                     
                       g 
                       * 
                     
                     = 
                     
                       
                         
                           argmax 
                           g 
                         
                          
                         
                           E 
                            
                           
                             ( 
                             g 
                             ) 
                           
                         
                       
                       - 
                       
                         λ 
                          
                         
                             
                         
                          
                         
                           C 
                            
                           
                             ( 
                             g 
                             ) 
                           
                         
                       
                     
                   
                   , 
                 
               
               
                 
                   ( 
                   13 
                   ) 
                 
               
             
           
         
       
     
     where λ is a regularization factor. Here it is denoted E(g)−λC(g) as the regularized energy of trace g. By properly choosing the hyper-parameter λ, the system can ensure that the regularized energy of a true breathing trace is positive, while when the observation area is empty, the regularized energy for any trace candidate in the given spectrum is negative. 
     Iterative Dynamic Programming 
     The problem in (13) can be solved by dynamic programming. However, dynamic programming typically can only find the trace with the maximum regularized energy and cannot deal with multiple breathing traces. The present teaching discloses a successive cancellation scheme to find multiple traces one by one via a novel method of iterative dynamic programming (IDP). 
     The principle idea of the IDP is intuitive. For a given spectrum S, the most probable breathing trace is first found by dynamic programming. To further determine if there are any other breathing traces, the identified trace will be erased from the spectrum, and then a new round of dynamic programming is performed to find another candidate trace. This successive cancellation procedure will be run iteratively until there is no more effective traces in the spectrum. 
     For clarity, (i, q) denotes the bin index with timestamp i and frequency component q. One may want to find the best trace of frequency peaks from timestamp i to j, which is denoted as g i   g j . Define the regularized energy of trace g i   g j  that ends at point (j, n) as s(g i   (j, n)). The disclosed approach is to search all possible traces g i   (j, n) that end at frequency point n and select the best one among them. This can be achieved by finding the optimal traces for all the bins along with the adjacent timestamps. For simplicity, one may denote the regularized energy at each bin as its score given by 
     
       
         
           
             
               
                 
                   
                     
                       s 
                        
                       
                         ( 
                         
                           i 
                           , 
                           q 
                         
                         ) 
                       
                     
                     = 
                     
                       
                         S 
                          
                         
                           ( 
                           
                             i 
                             , 
                             q 
                           
                           ) 
                         
                       
                       + 
                       
                         max 
                          
                         
                           { 
                           
                             
                               s 
                                
                               
                                 ( 
                                 
                                   
                                     i 
                                     - 
                                     1 
                                   
                                   , 
                                   
                                     q 
                                     ′ 
                                   
                                 
                                 ) 
                               
                             
                             + 
                             
                               λlog 
                                
                               
                                   
                               
                                
                               
                                 P 
                                  
                                 
                                   ( 
                                   
                                     
                                       q 
                                       ′ 
                                     
                                     , 
                                     q 
                                   
                                   ) 
                                 
                               
                             
                           
                           } 
                         
                       
                     
                   
                   , 
                   
                     
 
                   
                    
                   
                     i 
                     = 
                     2 
                   
                   , 
                   
                     3 
                      
                     
                         
                     
                      
                     … 
                   
                    
                   
                       
                   
                   , 
                   I 
                   , 
                   
                     ∀ 
                     q 
                   
                   , 
                   
                     
                       q 
                       ′ 
                     
                     ∈ 
                     Q 
                   
                   , 
                 
               
               
                 
                   ( 
                   14 
                   ) 
                 
               
             
           
         
       
     
     where s(1, q)=S(1, q)+λ log P(g(1)=q). The score of a given bin is the maximum achievable regularized energy that it can obtain. In other words, it determines the optimal paths that pass through bin (i, q). 
     The entire optimal breathing trace can be found by backtracking the bins that contribute to the maximum score g*(I) of the last timestamp. For the rest of the breathing trace in the observation window, i.e., ∀i=I−1, I−2, . . . , 1, one can have 
     
       
         
           
             
               
                 
                   
                     
                       g 
                       * 
                     
                      
                     
                       ( 
                       i 
                       ) 
                     
                   
                   = 
                   
                     
                       
                         argmax 
                         
                           ∀ 
                           
                             q 
                             ∈ 
                             Q 
                           
                         
                       
                        
                       
                         s 
                          
                         
                           ( 
                           
                             i 
                             , 
                             q 
                           
                           ) 
                         
                       
                     
                     + 
                     
                       λlog 
                        
                       
                           
                       
                        
                       
                         
                           P 
                            
                           
                             ( 
                             
                               q 
                               , 
                               
                                 
                                   g 
                                   * 
                                 
                                  
                                 
                                   ( 
                                   
                                     i 
                                     + 
                                     1 
                                   
                                   ) 
                                 
                               
                             
                             ) 
                           
                         
                         . 
                       
                     
                   
                 
               
               
                 
                   ( 
                   15 
                   ) 
                 
               
             
           
         
       
     
     The backtracking procedure in (15) gives the optimal trace g* for a given spectrum, which is the optimal solution for (13). 
     To further check if there are any other candidate breathing signals in the given spectrum, the trace g* should be removed. For the ideal case, one may only need to remove the bins along g*. However, since the number of FFT points are limited, the energy of the breathing signal is diffused around the center of breathing trace, which forms an energy strip in the given spectrum as shown in  FIG. 3 . Thus, if one may only remove the energy along the optimal trace g* and consecutively execute dynamic programming in (14) and (15), one will get a group of traces inside one energy strip. Therefore, IDP applies a windowing module on the optimal trace g* to emulate the diffusing effect of FFT to get an energy strip. The updated spectrum after one erases the optimal energy strip is 
         S ( i )← S ( i )− S ( i,g *( i ))* w, ∀i= 1,2, . . .  I,   (16)
 
     where S(i) denotes the energy of spectrum at timestamp i, and w is the frequency response of the windowing module. Operator * denotes convolution operation, which can emulate the energy stripe caused by the diffusing effect of FFT. 
     One may recursively perform the above dynamic programming and spectrum cancellation to find multiple traces. The algorithm terminates when the score of the found trace is negative, indicating an empty spectrum without any effective traces. 
     The procedure of iterative dynamic programming is summarized in  FIG. 16 .  FIGS. 6A-6C  illustrate the details of this finding-then-erasing procedure, where 3 people sit in car doing natural breathing and their average breathing rate are [10 14 15] bpm. In  FIG. 6A , the trace found by DP is marked by the line. The energy stripe of this trace is removed as shown in  FIG. 6B . The spectrogram, when IDP terminates, is shown in  FIG. 6C , and lines in the figure indicate the breathing traces. It is clear to see that although there is still some residual energy not perfectly removed, IDP terminates properly since there are no traces satisfying the constraint of non-negative regularized energy. 
     Detecting Empty Case 
     Ideally, when there is no person present in the monitoring area, no breathing trace would be picked up since the spectrum would be random due to the normal distribution of the thermal noise. In reality, however, false traces could be detected since some noise might be boosted in the empty case. To avoid this effect, one may employ motion detection to determine empty cases. If no motion (not even chest movement) is detected, the system will directly claim empty; otherwise, the above steps are performed to find a potential breathing rate trace. Here the motion detector needs to be sensitive and robust enough to detect breathing motion. In the present teaching, one may employ the motion statistics, which achieves almost zero false alarm. 
     Trace Concatenating 
     Iterative dynamic programming provides the breathing rate traces for each time window. In practice, a continuous monitoring system, however, would operate for much longer time than a time window, posing extra information gains to enhance the trace extraction. In this part, the present teaching discloses a novel trace concatenating algorithm ( FIG. 16 ) to concatenate trace segments belonging to the same breathing signal in different time windows, which not only improves the trace segments, but also enables detection of the start and end time of each trace (or equivalently, the entering and leaving time of a specific user). 
     For clarity, one may store all disclosed traces in a database. The jth trace found previously is denoted as g j   pre (t st :t end ), where j=1, . . . , J and t st  and t end  denote the start and end time of the trace. The kth traces found in the current time window [t−W, t] is denoted as g k (t−W:t), where k=1, . . . , K. Furthermore, the similarity between two traces is defined as the ratio between the overlapped time in the window and the window length, which is expressed as 
     
       
         
           
             
               
                 
                   
                     
                       f 
                        
                       
                         ( 
                         
                           
                             g 
                             j 
                             pre 
                           
                           , 
                           
                             g 
                             k 
                           
                         
                         ) 
                       
                     
                     = 
                     
                       
                          
                         
                           1 
                            
                           
                             ( 
                             
                               
                                 
                                   g 
                                   j 
                                   pre 
                                 
                                  
                                 
                                   ( 
                                   
                                     
                                       t 
                                       st 
                                     
                                     : 
                                     
                                       t 
                                       end 
                                     
                                   
                                   ) 
                                 
                               
                               = 
                               
                                 
                                   g 
                                   k 
                                 
                                  
                                 
                                   ( 
                                   
                                     t 
                                     - 
                                     
                                       W 
                                       : 
                                       t 
                                     
                                   
                                   ) 
                                 
                               
                             
                             ) 
                           
                         
                          
                       
                       
                         I 
                         - 
                         1 
                       
                     
                   
                   , 
                 
               
               
                 
                   ( 
                   17 
                   ) 
                 
               
             
           
         
       
     
     where ƒ(g j   pre , g k )∈[0,1]. A similarity matrix F∈   J ×   K  can be calculated according to (17) to show the similarity between all the traces in the current window and those in the database. In order to find the previous part for g k (t−W:t), one may only need to find the maximum item of f(k), which is the k-th column of F. The row index of the maximum similarity indicates the index of the previous trace if the maximum similarity is above a predefined threshold. 
     If there exists a previous trace with a high enough similarity, it means that the corresponding breathing rate trace has been detected before. Then the endpoint of the corresponding trace should be updated. One may let the endpoint be the current time and update the corresponding frequency component accordingly. In case a new user arrives, there will be no existing traces that have a similarity larger than the threshold and thus a new trace is created with the corresponding timestamps and frequency components. Similarly, no trace in the current window being similar to the past traces corresponds to a user that has left, and thus the trace would be terminated. 
       FIGS. 7A-7D  and  FIG. 8  show the effect of trace concatenating algorithm. Four adjacent time windows are shown in  FIGS. 7A-7D , and traces found by IDP are marked by lines. One can see that although the breathing trace in the middle of the spectrogram is not detected in the second and third window (due to body motion as well as breathing rate change of the subject), since the trace found in the fourth window still achieves high similarity with the trace found in the first window, it still can be concatenated as shown in  FIG. 8 . 
     People Counting and Recognition 
     People Counting 
     IDP and trace concatenation provides the estimation of breathing rate traces, and the trace number would be the estimate of occupancy level. Although the IDP and trace concatenating have considered the stability of human breath in the observation area, the estimation result may still suffer from large noise and have some false alarms or underestimations for a real-time output as shown in  FIG. 7B ,  FIG. 7C . To eliminate/mitigate these outliers for a real-time system, one may design a quasi-bilateral filter to explore the information contained in the previous estimations. Similar to the bilateral filter, the designed filter considers the distance in time and estimation domain simultaneously, but one may make some improvements according to the disclosed system. First, for a real-time system, the filter can only use the past and current estimation result. Furthermore, since IDP and trace concatenation leverage time as well as frequency information to get continuous breathing rate traces, the preliminary estimations are consistent in a short period. Thus, if one may directly use a bilateral filter, only the first incorrect output will be rectified. Given these two constraints, one may develop a segment-based filter, where each segment is a consistent preliminary estimation sequence. 
     Specifically, the output is determined by the current estimation and the previous segments. One may denote the weight of segment s as W seg (S) expressed as 
         W   seg ( s )= w ( l   s )* w (τ s )* w ( d   s )  (18)
 
     where l s  is the length of segment s, and τ s  is the time difference between segment s and current timestamp. d s  is the estimation difference between current estimation and segment s as shown in  FIG. 9 . Intuitively, the longer the segment is, the greater weight will be assigned. In contrary, the larger the distance is, no matter in time or the estimate of the crowd number, the smaller the influence of this segment imposing on the current result. For clarity, the set of segments with i estimated people is denoted as S i , and the current estimated number as j. The weight that the currently estimated people is i after quasi-bilateral filter can be calculated by 
     
       
         
           
             
               
                 
                   
                     
                       p 
                        
                       
                         ( 
                         i 
                         ) 
                       
                     
                     ← 
                     
                       
                         1 
                         N 
                       
                        
                       
                         ( 
                         
                           
                             ∑ 
                             
                               s 
                               ∈ 
                               
                                 S 
                                 i 
                               
                             
                           
                            
                           
                             
                               I 
                               s 
                             
                             
                               τ 
                               s 
                             
                           
                         
                         ) 
                       
                        
                       
                         e 
                         
                           - 
                           
                             d 
                             s 
                           
                         
                       
                     
                   
                   , 
                 
               
               
                 
                   ( 
                   19 
                   ) 
                 
               
             
           
         
       
     
     where N is the total number of segments, the estimation difference is d s =|i−j|, and W seg (s) in (18) is designed as 
     
       
         
           
             
               
                 
                   
                     
                       W 
                       seg 
                     
                      
                     
                       ( 
                       s 
                       ) 
                     
                   
                   ← 
                   
                     
                       
                         I 
                         s 
                       
                       
                         τ 
                         s 
                       
                     
                      
                     
                       
                         e 
                         
                           - 
                           
                             d 
                             s 
                           
                         
                       
                       . 
                     
                   
                 
               
               
                 
                   ( 
                   20 
                   ) 
                 
               
             
           
         
       
     
     The eventual result after filtering is j′, given by 
     
       
         
           
             
               
                 
                   
                     j 
                     ′ 
                   
                   = 
                   
                     
                       argmax 
                       i 
                     
                      
                     
                       p 
                        
                       
                         ( 
                         i 
                         ) 
                       
                     
                   
                 
               
               
                 
                   ( 
                   21 
                   ) 
                 
               
             
           
         
       
     
       FIG. 9  shows the estimation results before and after quasi-bilateral filtering. Clearly, the novel quasi-bilateral filter can remove the estimation outliers effectively, and thus improve the performance of people counting system. 
     Human Recognition in Smart Homes. 
     In this part, one may apply the disclosed respiration tracking result to an interesting smart home application, where one may want to recognize human identity in the observation area. Based on observations, although at some time instances, the breathing rate of different people can be the same, for a specific person, his or her breathing rate tends to locate in a certain range, which is a quite unique feature for human/user recognition. In other words, the breathing distribution of different people tends to be different. Motivated by this observation, one may utilize hypothesis-testing to do human recognition leveraging the breathing traces obtained. 
     The probability density function (PDF) of each person is assumed to follow a Gaussian distribution, i.e., p k (θ)˜ (μ k , σ k ), where k indicates the label of the testing subject. To obtain the breathing rate distribution of different people, one may first get the rough PDF estimation from the histogram in the training dataset. This histogram will be fitted into a Gaussian model to get PDF for each testing subject.  FIG. 10  shows exemplary breathing PDFs for 4 subjects. Based on the PDF distribution, for a certain observation of breathing trace g, the log-likelihood of the trace belonging to subject k can be calculated by 
         ( k )=Σ n=1   N  log( p   k ( g ( n ))),  (22)
 
     where N is the number of time instances of a given trace. The predicted label should be the one that achieves the maximum likelihood, i.e., 
     
       
         
           
             
               
                 
                   K 
                   = 
                   
                     
                       
                         argmax 
                          
                         
                             
                         
                       
                       k 
                     
                      
                     
                       
                         ℒ 
                          
                         
                           ( 
                           k 
                           ) 
                         
                       
                       . 
                     
                   
                 
               
               
                 
                   ( 
                   23 
                   ) 
                 
               
             
           
         
       
     
     Experiments and Evaluation: extensive experiments are conducted to evaluate the performance of the disclosed approach. Specifically, one may first introduce the experimental setup and then the results corresponding to two different scenarios. Discussion on the impact of distinct modules is disclosed at the end. 
     All the data in the experiments are collected in an on-campus lab and a car over two months with 12 participants. Two devices (Tx and Rx) are put on two different sides of a round deskParticipants are invited to sit in chairs as if they were attending a meeting. During the experiments, the participants randomly choose their seats and slight movements are allowed. One may also conduct experiments in a car, which is an extreme case for indoor scenario, where there is limited space as well as strong reflection. For the car scenario, the Tx and Rx are put at the front door on the driver and passenger side respectively. 
     Overall Performance 
       FIG. 11A  shows the confusion matrix of the disclosed method in the LAB, and the overall accuracy is 87.14%, with the accuracy defined as 
     
       
         
           
             
               
                 
                   Acc 
                   = 
                   
                     
                       
                         # 
                          
                         
                             
                         
                          
                         of 
                          
                         
                             
                         
                          
                         predicted 
                          
                         
                             
                         
                          
                         label 
                          
                         
                             
                         
                          
                         equals 
                          
                         
                             
                         
                          
                         true 
                          
                         
                             
                         
                          
                         label 
                       
                       
                         total 
                          
                         
                             
                         
                          
                         # 
                          
                         
                             
                         
                          
                         of 
                          
                         
                             
                         
                          
                         samples 
                       
                     
                     . 
                   
                 
               
               
                 
                   ( 
                   24 
                   ) 
                 
               
             
           
         
       
     
     The counting error is within 1 person for 98.6% of the testing cases. Additionally, the disclosed system can perfectly detect whether the monitoring area is occupied or not. The accuracy however, decreases with more people present. This is as expected since the more people there are, the more likely their breathing traces may merge together and the more likely occasional motion may happen, both leading to counting errors.  FIG. 12A  shows that the disclosed testing result in the car can achieve a comparable performance with that in the LAB, which demonstrates the independence of the disclosed system on the environment. 
     To further evaluate the disclosed system, one may compare it with the most relevant TR-BREATH which also estimates multi-person breathing rates using commercial WiFi. TR-BREATH employs root-MUSIC for breathing rate estimation and uses the affinity propagation algorithm to estimate crowd number. In order to make fair comparison, quasi-bilateral filter is used to filter out the outliers of original TR-BREATH estimations. The estimation accuracy of TR-BREATH in LAB and car are shown in  FIG. 11B  and  FIG. 12B  respectively. As seen, TR-BREATH shows a comparable performance in the car testing scenarios. The performance in the LAB environments is much worse, with an overall accuracy of 70.68%. The disclosed approach improves the overall performance by 16.46% and 3.32% for LAB and car testing scenario respectively, attributed to its three core techniques: adaptive SC combination, iterative dynamic programming, and trace concatenation. 
       FIG. 13  shows the confusion matrix of people recognition, where the PDFs of each individual are shown in  FIG. 10 . One can see that when the subject has a distinct breathing rate, it corresponds to a high recognition rate (i.e., subject  1  and subject  2 ). But for the case that the two subjects have very similar breathing rate ranges, it is hard to distinguish from each other (i.e., subject  3  and subject  4 ), and this is also the reason for underestimations in the people counting system. 
     Performance Gain of Individual Modules: how each independent module improves the performance of the disclosed system is discussed below. Apart from the confusion matrix and accuracy, here one may additionally adopt true positive (TP) rate, which is calculated as: 
     
       
         
           
             
               
                 
                   
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     Impact of SNR Boosting Algorithm 
     Here, one may compare the SNR boosting algorithm with the commonly used one, i.e., selecting the SCs whose maximum energy are above a certain threshold (hereafter, it is called fixed threshold algorithm). For fair comparison, one may choose the 30% of the maximum link energy as the threshold for both of the methods. Furthermore, the energy of each link is normalized before link combination, thus the parameters used in later process for both methods are also the same. It turns out that the disclosed algorithm shows better performance. 
     Impact of IDP Estimation Algorithm 
     In this experiment, one may show the benefits of the IDP. One may compare the performance with a local estimation algorithm that estimates the number of people based on the spectrum at current timestamp only. For fair comparison, the quasi-bilateral filter is also applied to the local estimation algorithm. The results shows that IDP considerably improves the performance for both datasets, which demonstrates the gains contributed by leveraging time diversity in counting. 
     Impact of Quasi-Bilateral Filter 
     In this experiment, one may show the effect of the designed quasi-bilateral filter on the performance of the people counting system.  FIG. 11C  and  FIG. 12C  shows the confusion matrix of people counting system without filtering on datasets collected in LAB and car respectively. By comparing the result with  FIG. 11A  and  FIG. 12A , one can see that the quasi-bilateral filter can improve the performance in most cases, especially when the number of people is larger than 3 in the observation area. The reason is that when the number of subjects increases, more motion interference will be introduced. Furthermore, it is more likely that different breathing traces will merge. Even though one may utilize the time domain as well as frequency diversity by IDP, estimation error still can occur. Quasi-bilater filter is a post-processing method that will further utilize the divisity in time domain and thus correct the estimate outliers. 
     To further investigate the impact of spatial separation as well as respiration rate difference of human subjects, one may perform experiments with 3 participants sitting with different spatial separations, as shown in  FIG. 14 . Considering the volume of a human subject, the minimum distance is set as 70 cm. The distance between Tx and Rx is 3.2 m. To ensure a constant breathing rate separation during the experiments, each of the subjects performs controlled breathing according to a metronome. The breathing rate separations of [0.5, 1, 1.5, 2] BPM are evaluated, respectively.  FIG. 15  shows the performance of the disclosed system, where the 4-tuple (*; *; *; *) denotes the detection accuracy and the relative breathing rate accuracy with the 3 users at location a, b, and c respectively. One can see that the breathing rate separation has a significant impact on the performance, while the impact of the spatial separation is negligible. The detection rate raises more than 30% when the breathing rates separation increases from 0.5 BPM to 1 BPM. The system achieves 100% detection rate once the breathing rate separation is above 1.5 BPM. Besides, as long as the breathing rate trace has been detected, the disclosed system can accurately estimate the breathing rate, and the breathing estimation accuracy is above 94.7% for all of the test case. 
     Random body motion is one of the most challenging problems for wireless vital sign monitoring. To combat the impact of slight motion, the present teaching discloses an adaptive subcarrier selection algorithm as well as iterative dynamic programming to extract the breathing rate trace. However, it is hard to accurately extract the breathing signal when continuous large motion such as walking is present due to the inherent limitation of wireless sensing. As long as there is no continuous large motion, which is usually the case for most wireless monitoring applications, the disclosed system can correctly pick up the breathing rate traces. 
     There are indeed dedicated systems designed to detect the dip events of RSS of WiFi systems when humans are walking and estimate the crowd number. Gait information can also be extracted from WiFi systems to do human recognition. However, those systems are specifically designed for the case when the subjects need to keep walking. The disclosed system can perform crowd counting and recognition when the subjects are static. 
     Recall the experiments performed in a car to verify that the disclosed system is independent of the environment, during which the car engine is on but the car is not moving. 
     The disclosed respiration tracking method performs well with the slightly vibration introduced by the engine, however, it may not work well in a moving car since the vibration from a running car is large enough to overwhelm the minute vital signals. However, once the car is static, e.g., waiting before the traffic light, the disclosed system can track the respiration rate traces for crowd counting and human recognition. Handling car vibration during driving is a great common challenge faced by various sensing techniques, not only RF-based but also vision-based approaches. 
     The present teaching also proposes a new breathing detection and people counting engine (Breathing3). This Breathing3 engine assumes that there are multiple antenna links, say, N1 links. For each link, it obtains a time series of channel information (TSCI) (e.g. CI may be channel state information, CSI), with N2 components for each CI. There are N1 TSCI. Each TSCI can be decomposed into N2 components TSCI. Thus, there are N1×N2 component TSCI. The CI may comprise N2 components: frequency information (e.g. CFR) or time information (e.g. CIR). Each CI is associated with a time stamp. A transformation may be applied to a CI with N2 components to convert it to a CI with N2 transformed components. For example, frequency transform may be applied to a CI with N2 time component to transform it into a CI with N2 frequency component. Similarly, inverse frequency transform may be applied to a CI with N2 frequency component to transform it into a CI with N2 time component. A component TSCI may be formed by a particular component (e.g. the first component, or the second component, etc.) of all the CI in a TSCI. Thus, there are N1*N2 component TSCI, each associated with one of the N2 components and one of the N1 links. 
     Breathing3 divides the time axis into overlapping time windows. For each sliding time window and for each CIC index, it performs a time-frequency transform (TFT, e.g. short-time Fourier Transform (STFT) or wavelet, etc.). A total of N1×N2 TFS is performed in the sliding time window, one for each component TSCI in the corresponding sliding time window. The sliding time window length may be adjusted over time—large when high breathing precision is need, medium size when normal precision is ok and small when low precision is sufficient. Sometimes, the sounding signal may be delayed momentarily due to network traffic/congestion causing the CI sampling/extraction (e.g. done by a wireless IC) to have irregular time intervals (i.e. time stamps of CI are irregular). The sounding signal may be a wireless signal from Type 1 device to Type 2 device, and may be a training of impulses/sounding pulses sent at regular time interval over a period of time. Thus, sampling time correction may be applied to ensure that the CI are sampled at regular intervals. Correction may be achieved by performing temporal interpolation at the desired sampling time instances. Sometimes each TSCI may be sampled at different sampling frequency (e.g. one sampled at 300 Hz, another one at 150 Hz and still another one at 105 Hz). Sampling time correction may be applied. All TSCI may be corrected such that all are sampled at the same sampling frequency and sampling instances. 
     For the sliding time window, Breathing3 forms a number of characteristics intermediate time-frequency transform (CITFT), and then combines them into a combined time-frequency transform (CTFT). The CITFT may be computed for each link such that, for each time-frequency index (of the TFT) and for each link (one of the N1 links, between a pair of TX and RX antennas), the CITFT may be computed as a first characteristics value among the N2 TFT values of that link with the time-frequency index and any component index. There are N1 such CITFT. For the time-frequency index (of the TFT), the CTFT is a second characteristic value of the N1 CITFT. The CITFT may be computed for each component such that, for each time-frequency index (of the TFT) and for each component (one of the N2 components of each CI), the CITFT may be computed as a first characteristics value among the N2 TFT values of that link with the time-frequency index and any component index. There are N2 such CITFT. For the time-frequency index (of the TFT), the CTFT is a second characteristic value of the N2 CITFT. The sliding time window length may be adjusted over time. For example, the sliding time window length is large when high breathing precision is needed, has a medium size when normal precision is ok, and is small when low precision is sufficient. 
     The characteristics may be the TFT value with maximum magnitude, minimum magnitude, average magnitude, a percentile magnitude, maximum phase, minimum phase, average phase, a percentile phase, mean, medium, mode, trimmed mean, weighted average, or another characteristics value. The characteristics may also be the maximum magnitude, the minimum magnitude, the average magnitude, the percentile magnitude, the maximum phase, the minimum phase, the average phase, the percentile phase, the mean, the medium, the mode, the trimmed mean, the weighted average, or the another characteristics. The characteristics may be the TFT value with maximum magnitude, minimum magnitude, average magnitude, a percentile magnitude, maximum phase, minimum phase, average phase, a percentile phase, mean, medium, mode, trimmed mean, weighted average, or another characteristics value after a nonlinear function is applied to the TFT value. The nonlinear function may be logarithm, an exponential function, a polynomial function or another nonlinear function. The characteristics may also be the maximum magnitude, the minimum magnitude, the average magnitude, the percentile magnitude, the maximum phase, the minimum phase, the average phase, the percentile phase, the mean, the medium, the mode, the trimmed mean, the weighted average, or the another characteristics after the nonlinear function is applied to the TFT value. 
     For example, each CI may be a 128-point CFR. TFT may be 512-point STFT (with frequency index, i, being from 0 to 127). The characteristics may be the value with maximum magnitude. Suppose there are N1=2×3=6 links. Then for each STFT frequency index (e.g. i=1), there are 6 STFT values (one for each of N1 link). The CTFT at the frequency index i=1 is simply the STFT at i=1 with maximum magnitude. If a sliding time window is short enough (e.g. 1 second), the human breathing can be approximated as a periodic function which corresponds to a dominant peak in the CTFT and the frequency or period associated with the dominant peak is the corresponding breathing frequency or breathing period. Thus, in Breathing3, for each sliding time window, dominant peaks of the CTFT are determined. A number of breathing rates (which should be equal to the number of people present) are computed based on the time-frequency index (e.g. frequency of STFT) associated with dominant peaks of CTFT. In addition, the number of people present is deduced from the number of breathing rate. 
     Sometimes, false peaks may occur due to noise or other conditions. To suppress false peaks, one may note that a true peak (i.e. a true breathing rate of a person) should NOT happen only at one time instance but should last over time forming a “breathing trace” of the peak over time. One can associate each sliding time window with a time t (e.g. its starting time). When time difference between adjacent sliding time window is small, the breathing of any human should not change abruptly. Thus, the breathing trace should be slowly varying (or consistent). Thus, in Breathing3, any breathing trace candidate that changes abruptly (or very fast) are suppressed, if not eliminated. For example, the breathing trace may be obtained by dynamic programming with a cost function that penalizes fast breath rate changes. 
     In Breathing3, dominant peaks of multiple sliding time window in a testing period from T1 to T2 (i.e. T1&lt;=t&lt;=T2, or sliding time windows with starting time between T1 and T2) are considered together in search of long-term “consistent” breathing. A number of breathing traces are obtained each by connecting adjacent dominant peaks (one peak from each sliding time window) in the candidate time period (e.g. using dynamic programming). A dominant peak may appear in more than one breathing traces. 
     A constraint may be applied that a breathing trace must begin at T1 and end at T2. As such, different testing period may be considered so that one can detect new breathing trace (e.g. when a person just enters a room) and disappearing breathing traces (e.g. when a person leaves the room). The constraint may be relaxed so that a breathing trace can begin or end at any time within the testing period. 
     Cost function may be constructed such that abrupt-changing or fast changing breathing rates have high cost while smooth, continuous or slow-changing breathing rates have low cost. In Breathing3, a number of people may be associated with the number of breathing traces. At any time, the instantaneous number of people may be associated with the instantaneous number of breathing trace at that time. 
     In various embodiments of the present teaching, a driver authentication or recognition may be performed based on a frequency hopping method for monitoring and recognition, e. g. as disclosed in the following clauses. 
     Clause 1: A method of a channel-hopping target recognition system, comprising: for each of at least one known target in a venue in a respective training time period: transmitting, by an antenna of a first Type 1 heterogeneous channel-hopping wireless device (wireless transmitter), a respective training channel-hopping wireless signal to at least one first Type 2 heterogeneous channel-hopping wireless device (wireless receiver) through a wireless multipath channel impacted by the known target at the location in the venue in the training time period, wherein the wireless multipath channel comprises N1 channels, with N1 greater than or equal to one, wherein the respective training channel-hopping wireless signal hops among the N1 channels, obtaining, asynchronously by each of the at least one first Type 2 device based on the training channel-hopping wireless signal, N1 time series of training channel information (training CI), each time series of training CI (training TSCI) associated with one of the N1 channels of the wireless multipath channel between the first Type 2 device and the first Type 1 device in the training time period, wherein the N1 training TSCI are asynchronous due to channel-hopping and can be merged to form a combined time series of training CI (combined training TSCI), and pre-processing the N1 training TSCI; training at least one classifier for the at least one known target based on the respective N1 training TSCI of each of the at least one known target, wherein the at least one classifier to comprise at least one of: linear classifier, logistic regression, probit regression, Naive Bayes classifier, nonlinear classifier, quadratic classifier, K-nearest-neighbor, decision tree, boosted tree, random forest, learning vector quantization, linear discriminant analysis, support vector machine, neural network, perceptron, deep neural network, supervised learning, unsupervised learning, discriminative method, generative method, reinforced learning, Markov decision process, clustering, dimension reduction, K-mean, bagging, boosting, AdaBoost, stochastic gradient descent, and another classifier; and for a current target in the venue in a current time period, transmitting, by an antenna of a second Type 1 heterogeneous channel-hopping wireless device, a current channel-hopping wireless signal to at least one second Type 2 heterogeneous channel-hopping wireless device through the wireless multipath channel impacted by the current target in the venue in the current time period, wherein the current channel-hopping wireless signal hops among the N1 channels, obtaining, asynchronously by each of the at least one second Type 2 device based on the current channel-hopping wireless signal, N1 time series of current channel information (current TSCI), each current TSCI associated with one of the N1 channels of the wireless multipath channel between the second Type 2 device and the second Type 1 device in the current time period, wherein the N1 current TSCI are asynchronous due to channel-hopping and can be merged to form a combined time series of current CI (combined current TSCI), pre-processing the N1 current TSCI, and applying the at least one classifier to: classify at least one of: the N1 current TSCI, some of the N1 current TSCI, a particular current TSCI, a portion of the particular current TSCI, a combination of the portion of the particular current TSCI and another portion of an additional TSCI, a portion (in time) of the N1 current TSCI, and a combination of the portion of the N1 current TSCI and another portion of an additional N1 TSCI, and associate the current target with at least one of: one of the at least one known target, a variant of the known target, an unknown target, and another target, wherein each target comprises at least one of: a subject, a human, a baby, an elderly person, a patient, a pet, a dog, a cat, an object, an object comprising a particular material, a machine, a device, an apparatus, a tool, a part, a component, a liquid, a fluid, a mechanism, a change, a presence, an absence, a motion, a periodic motion, a transient motion, a movement, a location, a change of the subject, a gesture of a human, a gait of a human, a movement of a human, a change of the object, a movement of the object, a layout, an arrangement of objects, and an event, wherein a training TSCI associated with a first Type 2 device and a current TSCI associated with a second Type 2 device have at least one of: different starting times, different time durations, different stopping times, different counts of items in their respective time series, different sampling frequencies, different sampling periods between two consecutive items in their respective time series, different sounding rate, different sounding period, different order of channel-hopping, different duration of remaining in a particular channel, different timing, different channels for hopping, and channel information (CI) with different features. 
     Clause 2: The method of the channel-hopping target recognition system of Clause 1, further comprising: aligning a first section (of a first time duration) of a first set of TSCI and a second section (of a second time duration) of a second set of TSCI, and determining a mapping between items of the first section and items of the second section, wherein the first set of TSCI is associated with a subset of the N1 channels and the second set of TSCI is associated with the same subset of the N1 channels. 
     Clause 3: The method of the channel-hopping target recognition system of Clause 2, wherein: the first set of TSCI is pre-processed by a first operation; the second set of TSCI is pre-processed by a second operation; and at least one of: the first operation, and the second operation, comprises at least one of: combining, grouping, subsampling, re-sampling, interpolation, filtering, transformation, feature extraction, and pre-processing. 
     Clause 4: The method of Clause 2, further comprising: mapping a first item of the first section to a second item of the second section, wherein at least one constraint is applied on at least one function of at least one of: the first item of the first section of the first set of TSCI; another item of the first set of TSCI; a time stamp of the first item; a time difference of the first item; a time differential of the first item; a neighboring time stamp of the first item; another time stamp associated with the first item; the second item of the second section of the second set of TSCI; another item of the second set of TSCI; a time stamp of the second item; a time difference of the second item; a time differential of the second item; a neighboring time stamp of the second item; and another time stamp associated with the second item. 
     Clause 5: The method of Clause 4: wherein the at least one constraint to comprise at least one of: a difference between the time stamp of the first item and the time stamp of the second item is bounded by at least one of: an adaptive upper threshold and an adaptive lower threshold, a difference between a time differential of the first item and a time differential of the second item is bounded by at least one of: an adaptive upper threshold and an adaptive lower threshold, and a difference between a time difference between the first item and another item of the first section and a time difference between the second item and another item of the second section is bounded by at least one of: an adaptive upper threshold and an adaptive lower threshold. 
     Clause 6: The method of Clause 1, further comprising: determining an active section (of a time duration) of a set of TSCI adaptively; and determining a starting time and an ending time of the active section, wherein determining the active section comprises: computing a tentative section of the set of TSCI, and determining the active section by removing a beginning non-active portion and an ending non-active portion of the tentative section. 
     Clause 7: The method of Clause 6, wherein determining the section further comprises: determining the beginning portion of the tentative section by: considering items of the tentative section with increasing time stamp as a current item iteratively, one item at a time, computing recursively an activity measure associated with at least one of: the current item associated with a current time stamp, past items of the tentative section with time stamps not larger than the current time stamp, and future items of the tentative section with time stamps not smaller than the current time stamp, and adding the current item to the beginning portion of the tentative section when a first criterion associated with the activity measure is satisfied; and determining the ending portion of the tentative section by: considering items of the tentative section with decreasing time stamp as a current item iteratively, one item at a time, iteratively computing and determining at least one activity measure associated with at least one of: the current item associated with a current time stamp, past items of the tentative section with time stamps not larger than the current time stamp, and future items of the tentative section with time stamps not smaller than the current time stamp, and adding the current item to the ending portion of the tentative section when a second criterion associated with the at least one activity measure is satisfied. 
     Clause 8: The method of Clause 7: wherein at least one of the first criterion and the second criterion comprises at least one of: the activity measure is smaller than an adaptive upper threshold, the activity measure is larger than an adaptive lower threshold, the activity measure is smaller than an adaptive upper threshold consecutively for at least a predetermined amount of consecutive time stamps, the activity measure is larger than an adaptive lower threshold consecutively for at least an additional predetermined amount of consecutive time stamps, the activity measure is smaller than an adaptive upper threshold consecutively for at least a predetermined percentage of the predetermined amount of consecutive time stamps, the activity measure is larger than an adaptive lower threshold consecutively for at least another predetermined percentage of the additional predetermined amount of consecutive time stamps, another activity measure associated with another time stamp associated with the current time stamp is smaller than another adaptive upper threshold and is larger than another adaptive lower threshold, at least one activity measure associated with at least one respective time stamp associated with the current time stamp is smaller than respective upper threshold and larger than respective lower threshold, and a percentage of time stamps with associated activity measure smaller than respective upper threshold and larger than respective lower threshold in a set of time stamps associated with the current time stamp exceeds a threshold; and wherein the activity measure associated with an item at time T1 comprises at least one of: a first function of the item at time T1 and an item at time T1−D1, wherein D1 is a pre-determined positive quantity, a second function of the item at time T1 and an item at time T1+D1, a third function of the item at time T1 and an item at time T2, wherein T2 is a pre-determined quantity, and a fourth function of the item at time T1 and another item. 
     Clause 9: The method of Clause 8: wherein at least one of: the first function, the second function, the third function, and the fourth function, is at least one of: a function F1(x, y, . . . ) with at least two scalar arguments: x and y, a function F2(X, Y, . . . ) with at least two vector arguments: X and Y, and a function F3(X1, Y1, . . . ) with at least two arguments: X1 and Y1; wherein the function F1 is a function of at least one of the following: x, y, (x−y), (y−x), abs(x−y), x{circumflex over ( )}a1, y{circumflex over ( )}b1, abs(x{circumflex over ( )}a1−y{circumflex over ( )}b1), (x−y){circumflex over ( )}a1, (x/y), (x+a1)/(y+b1), (x{circumflex over ( )}a1/y{circumflex over ( )}b1), and ((x/y){circumflex over ( )}a1−b1), wherein a1 and b1 are predetermined quantities; wherein both X and Y are n-tuples such that X=(x_1, x_2, . . . , x_n) and Y=(y_1, y_2, . . . , y_n); the function F2 is a function of at least one of the following: x_i, y_i, (x_i−y_i), (y_i−x_i), abs(x_i−y_i), x_i{circumflex over ( )}a2, y_i{circumflex over ( )}b2, abs(x_i{circumflex over ( )}a2−y_i{circumflex over ( )}b2), (x_i−y_i){circumflex over ( )}a2, (x_i/y_i), (x_i+a2)/(y_i+b2), (x_i{circumflex over ( )}a2/y_i{circumflex over ( )}b2), and ((x_i/y_i){circumflex over ( )}a2−b2); wherein i, ranging from 1 to n, is a component index of the n-tuples X and Y; wherein both X1 and Y1 are n-tuples comprising N components such that X1=(x1_1, x1_2, . . . , x1_N) and Y1=(y1_1, y1_2, . . . , y1_N); wherein the function F3 comprises a component-by-component summation of another function of at least one of the following: x1_j, y1_j, (x1_j−y1_j), (y1_j−x1_j), abs(x1_j−y1_j), x1_j{circumflex over ( )}a3, y1_j{circumflex over ( )}b3, abs(x1_j{circumflex over ( )}a3−y1_j{circumflex over ( )}b3), (x1_j−y1_j){circumflex over ( )}a3, (x1_j/y1_j), (x1_j+a3)/(y1_j+b3), (x1_j{circumflex over ( )}a3/y1_j{circumflex over ( )}b3), and ((x1_j/y1_j){circumflex over ( )}a3−b3); and wherein j, ranging from 1 to N, is a component index of the n-tuples X1 and Y1. 
     Clause 10: The method of Clause 2, further comprising: computing the mapping using dynamic time warping (DTW), wherein the DTW comprises a constraint on at least one of: the mapping, the items of the first set of TSCI, the items of the second set of TSCI, the first time duration, the second time duration, the first section, and the second section. 
     Clause 11: The method of Clause 1, further comprising: aligning a first section (of a first time duration) of a first set of TSCI and a second section (of a second time duration) of a second set of TSCI; computing a map comprising a plurality of links between first items of the first section and second items of the second section, wherein each of the plurality of links associates a first item with a first time stamp with a second item with a second time stamp; computing a mismatch cost between the aligned first section and the aligned second section; applying the at least one classifier based on the mismatch cost, wherein the mismatch cost comprises at least one of: an inner product, an inner-product-like quantity, a quantity based on correlation, a quantity based on covariance, a discriminating score, a distance, a Euclidean distance, an absolute distance, an L_1 distance, an L_2 distance, an L_k distance, a weighted distance, a distance-like quantity and another similarity value, between the first vector and the second vector, and a function of: an item-wise cost between a first item of the first section of the first CI time series and a second item of the second section of the second CI time series associated with the first item by a link of the map, and a link-wise cost associated with the link of the map, wherein the aligned first section and the aligned second section are represented respectively as a first vector and a second vector that have same vector length, and wherein the mismatch cost is normalized by the vector length. 
     Clause 12: The method of Clause 11, further comprising: applying the at least one classifier to a plurality of first sections of the first set of TSCI and a plurality of respective second sections of the second set of TSCI; obtaining at least one tentative classification result, each tentative classification result being associated with a respective first section and a respective second section; and associating the current target with at least one of: the known target, the unknown target and the another target, based on a largest number of the at least one tentative classification result associated with at least one of: the known target, the unknown target and the another target. 
     Clause 13: The method of Clause 1, further comprising: training a projection for each CI using a dimension reduction method based on the N1 training TSCI associated with each known target, wherein the dimension reduction method comprises at least one of: principal component analysis (PCA), PCA with different kernel, independent component analysis (ICA), Fisher linear discriminant, vector quantization, supervised learning, unsupervised learning, self-organizing maps, auto-encoder, neural network, and deep neural network; applying the projection to each respective CI; training the at least one classifier based on the projection and the N1 training TSCI associated with each known target; classifying, by the at least one classifier, the N1 current TSCI based on the projection; and associating the N1 current TSCI with at least one of: the known target, the variant of the known target, the unknown target, and the another target. 
     Clause 14: The method of Clause 13, further comprising: a re-training comprising at least one of: re-training the projection using at least one of: the dimension reduction method, and an additional dimension reduction method, based on at least one of: the at least one classifier before the re-training, the projection before the re-training, the N1 training TSCI associated with each known target, the N1 current TSCI, and additional training TSCI, wherein the additional dimension reduction method comprises at least one of: a simplified dimension reduction method, principal component analysis (PCA), PCA with different kernels, independent component analysis (ICA), Fisher linear discriminant, vector quantization, supervised learning, unsupervised learning, self-organizing maps, auto-encoder, neural network, and deep neural network, and re-training the at least one classifier based on at least one of: the re-trained projection, the N1 training TSCI associated with each known target, the result of the application of the at least one classifier, and the N1 current TSCI; and classifying N1 next TSCI associated with the N1 channels based on at least one of: the re-trained projection, and the at least one re-trained classifier. 
     Clause 15: The method of Clause 1, further comprising: training a projection for each of a set of combined training CI using a dimension reduction method based on the N1 training TSCI associated with each known target, wherein each combined CI of a known target is associated with a particular time stamp, and is a combination of N1 CI with a CI associated with each of the N1 channels, each CI being computed from a time window of the corresponding training TSCI of the known target around to the particular time stamp, wherein the dimension reduction method comprises at least one of: principal component analysis (PCA), PCA with different kernel, independent component analysis (ICA), Fisher linear discriminant, vector quantization, supervised learning, unsupervised learning, self-organizing maps, auto-encoder, neural network, and deep neural network; applying the projection to each combined CI; training the at least one classifier based on the projection, the set of combined training CI of each known target, and the N1 training TSCI associated with each known target; and classifying, by the at least one classifier, the N1 current TSCI based on the projection. 
     Clause 16: The method of Clause 15, further comprising: a retraining comprising at least one of: re-training the projection using at least one of: the dimension reduction method, and an additional dimension reduction method, based on at least one of: the projection before the re-training, the set of combined training CI of each known target, the N1 training TSCI associated with each known target, the combined current TSCI, the N1 current TSCI, and additional training TSCI, wherein the additional dimension reduction method comprises at least one of: a simplified dimension reduction method, principal component analysis (PCA), PCA with different kernels, independent component analysis (ICA), Fisher linear discriminant, vector quantization, supervised learning, unsupervised learning, self-organizing maps, auto-encoder, neural network, and deep neural network, and re-training the at least one classifier based on at least one of: the re-trained projection, the set of combined training CI of each known target, the N1 training TSCI associated with each known target, the combined current TSCI, the N1 current TSCI, and the additional training TSCI; and classifying N1 next TSCI associated with the N1 channels based on at least one of: the re-trained projection, and the at least one re-trained classifier. 
     Clause 17: The method of Clause 1, further comprising: for each of at least one first section (of a first time duration) of the combined current TSCI: for each of the at least one known target: determining a respective second section (of a respective second time duration) of a respective representative combined training TSCI of the respective target, aligning the first section and the respective second section, and computing a mismatch cost between the aligned first section and the aligned respective second section, applying the at least one classifier, and obtaining a tentative classification of the first section based on the mismatch costs; obtaining a classification of the at least one first section result based on at least one of: the at least one tentative classification of each first section, the mismatch cost of each known target for each first section, the combined current TSCI, the combined training TSCI, and associating the at least one first section with at least one of: a known target, an unknown target and another target. 
     Clause 18: The method of Clause 17, further comprising: computing how many times each known target achieves a smallest mismatch cost; and associating the at least one first section with at least one of: a known target that achieves the smallest mismatch cost for most times, a known target that achieves a smallest overall mismatch cost, wherein an overall mismatch cost is a weighted average of at least one mismatch cost associated with the at least one first section, a known target that achieves a smallest cost based on another overall cost, and an unknown target, wherein the at least one first section is associated with the unknown target in at least one of the following situations: no target achieves a mismatch cost lower than a first threshold T1 in a sufficient percentage of the at least one first section, and no target achieves an overall mismatch cost lower than a second threshold T2. 
     Clause 19: The method of Clause 17; wherein the representative combined training CI time series associated with the known target is obtained based on the combined training TSCI associated with the known target and additional combined training TSCI associated with the known target. 
     Clause 20: The method of Clause 17: wherein the representative combined training TSCI associated with the known target is a particular combined training TSCI among the set of all possible combined training TSCI that minimizes an aggregate mismatch with respect to a training set of TSCI; wherein the training set of TSCI comprises the combined training TSCI associated with the known target and additional combined training TSCI associated with the known target; wherein the aggregate mismatch of a particular TSCI with respect to the training set is a function of at least one mismatch cost between the particular TSCI and each TSCI of the training set of TSCI, wherein both are aligned before the mismatch cost is computed; wherein the function comprises at least one of: average, weighed average, mean, trimmed mean, median, mode, arithmetic mean, geometric mean, harmonic mean, truncated mean, generalized mean, power mean, f-mean, interquartile mean, and another mean. 
     Clause 21: The method of Clause 20: wherein the particular combined training TSCI is in the training set of TSCI. 
     Clause 22: The method of Clause 20: wherein each TSCI is associated with a time duration; wherein a set of candidate time durations of the respective combined training TSCI are determined; wherein, for each candidate time duration, a respective optimal combined training TSCI with the candidate time duration minimizing the aggregate mismatch with respect to the training set of TSCI is computed; wherein the representative combined training TSCI is the particular optimal combined training TSCI with the particular time duration among the set of candidate time duration that minimizes the aggregate mismatch. 
     Clause 23: The method of Clause 22: wherein fast computation is applied in the search of the particular time duration, and the particular optimal combined training TSCI with the particular time duration. 
     Clause 24: The method of Clause 1, further comprising: determining a respective time window of a respective training TSCI for the training of a classifier for the at least one known target. 
     Clause 25: The method of Clause 1, further comprising: re-training a classifier for the at least one known target adaptively based on at least one of: a current TSCI, the combined current TSCI, a previous current TSCI and a pervious combined current TSCI. 
     Clause 26: The method of clause 25, further comprising: determining a time window associated with at least one of: the current TSCI, the combined current TSCI, the previous current TSCI and the previous combined current TSCI, for the re-training of the classifier for the at least one known target. 
     Clause 27: The method of Clause 1: wherein the venue is a vehicle and the current target is a passenger in the vehicle; wherein the at least one known target comprises a number of known passengers of the vehicle; wherein the at least one classifier to associate the current target with a known passenger. 
     Clause 28: The method of Clause 27: wherein at least two known targets comprise a particular known passenger with different postures in the vehicle; wherein the different postures comprise a body part of the particular known passenger at least one of: different positions, different orientation and different shape; wherein the at least one classifier to associate the current target with a passenger posture. 
     Clause 29: The method of Clause 27: wherein at least two known targets comprise a particular known passenger doing different movement in the vehicle; wherein the different movement comprise at least one of: a driver movement, driving straight, turning left, turning right, stepping on accelerator, stepping on brake, changing gear, adjusting turning signal, adjusting windshield wiper setting, adjusting visor, adjusting dashboard switches, adjusting mirror, adjusting window, reaching to the back, reaching to the side, reaching to center console, putting on a cap, adjusting seat, driving attentively, driving in a sleepy manner, a passenger movement, sitting quietly looking forward, looking sideway, sleeping, talking, checking phone, working on a laptop, stretching, adjusting window, and another movement; wherein the at least one classifier to associate the current target with a particular passenger movement. 
     Clause 30: The method of Clause 27: wherein at least two known targets comprise a particular known passenger in different states; wherein the states comprise at least one of: an emotional state, normal, depressed, excited, a physiological state, sleepy, alert, relax, tense; wherein the at least one classifier to associate the current target with a particular passenger state. 
     Clause 31: The method of Clause 27: wherein at least two known targets comprise a particular known passenger sitting at different locations in the vehicle; wherein the at least one classifier to associate the current target with a particular location in the vehicle. 
     Clause 32: The method of Clause 1: wherein the venue is a vehicle and the current target comprises two passengers in the vehicle; wherein at least two known targets are “single” targets each comprising a single known passenger of the vehicles; wherein the at least one classifier to associate the current target with two of the at least two single targets. 
     Clause 33: The method of Clause 32: wherein at least two known targets are single targets each comprising a particular known passenger with at least one of: different postures, different movement, different state, and another difference; wherein the at least one classifier to associate the current target with at least one of: a passenger posture, a passenger movement, a passenger state and another characteristics. 
     Clause 34: The method of Clause 1: wherein the venue is a vehicle and the current target comprises two passengers in the vehicle; wherein at least two known targets are “double” targets each comprising two known passengers of the vehicles; wherein the at least one classifier to associate the current target with one of the double targets. 
     Clause 35: The method of Clause 34: wherein at least two known double targets comprise a particular known passenger with at least one of: different postures, different movement, different state, and another difference. 
     Clause 36: The method of Clause 1: wherein the venue is a vehicle and the current target comprises a first number of passengers in the vehicle; wherein at least two known targets are “multi-targets” each comprising a respective second number of known passengers of the vehicle; wherein the second number is a non-negative integer not less than 0 and not greater than the first number; wherein the at least one classifier to associate the current target with at least one multi-target. 
     Clause 37: The method of Clause 36: wherein at least two of the known multi-targets comprise a particular known passenger with at least one of: different postures, different movement, different state, and another difference. 
     Clause 38: The method of Clause 1: wherein the venue is a vehicle and the current target comprises an unknown number of passengers in the vehicle; wherein at least two known targets are “multi-targets” each comprising a number of known passengers of the vehicles; wherein the at least one classifier to associate the current target with at least one multi-target, and an estimate of the unknown number based on the number of known passengers associated with each of the at least one multi-target. 
     Clause 39: The method of Clause 1: wherein the venue is a vehicle and the current target comprises an unknown number of passengers in the vehicle; wherein at least two known targets are “multi-targets” each comprising a number of known passengers of the vehicles; wherein the at least one classifier to associate the current target with an estimate of the unknown number. 
     Clause 40: The method of Clause 1: wherein the venue is a vehicle and the current target is a passenger at a particular position in the vehicle; wherein the at least one known target comprises a number of known passengers of the vehicle at a number of known positions in the vehicle; wherein the at least one classifier to associate the current target with the particular position of the vehicle. 
     Clause 41: The method of Clause 27: wherein the passenger sits at the driver seat of the vehicle. 
     Clause 42: The method of Clause 27: wherein the current motion happens before the vehicle is started comprising the passenger opening the driver-side front door, entering the vehicle and sitting at the driver seat of the vehicle. 
     Clause 43: The method of Clause 27: wherein, after the vehicle is turned off, the passenger sitting at the driver seat of the vehicle opens the driver-side front door, and exits the vehicle. 
     Clause 44: The method of Clause 27: wherein the current motion happens before the vehicle is started comprising the passenger opening the passenger-side front door, entering the vehicle and sitting at the seat next to the driver&#39;s seat of the vehicle. 
     Clause 45: The method of Clause 27: wherein the passenger sitting at the seat of the vehicle next to the driver seat opens the passenger-side front door and exits the vehicle. 
     Clause 46: The method of Clause 27: wherein the current motion happens before the vehicle is started comprising the passenger opening a back door, entering the vehicle and sitting at a seat in the second row of the vehicle. 
     Clause 47: The method of Clause 27: wherein the current motion happens before the vehicle is started comprising the passenger opening a back door, entering the vehicle and sitting at a position behind the second row of the vehicle. 
     Clause 48: The method of Clause 27: wherein the current motion happens before the vehicle is started comprising the opening of a front door, the passenger entering the vehicle and sitting at a position behind the first row of the vehicle. 
     Clause 49: The method of Clause 1: wherein the venue is a vehicle; wherein at least one classifier is trained or re-trained for: a number of known targets each being the vehicle being one of a number of known candidate vehicles, a number of known targets each being the vehicle in a known state, a target being the vehicle with all doors and windows closed, a number of known targets each being the vehicle with all doors closed and one window opened to a known degree, a number of known targets each being the vehicle with all doors closed and a number of windows opened to respective known degrees, a number of known targets each being the vehicle with driver door opened to a known degree and the other doors closed, a number of known targets each being the vehicle with front passenger door opened to a known degree and the other doors closed, a number of known targets each being the vehicle with a back door opened to a known degree and the other doors closed, a number of known targets each being the vehicle with a number of doors opened to respective known degrees and the other doors closed, a number of known targets each being the vehicle with tail gate opened and the other doors closed, a number of known targets each being the vehicle with seats at respective known positions, known angles and known settings, a number of known targets each being the vehicle with accessories at respectively known settings, a number of known targets each being the vehicle with a number of seats occupied by passengers, a number of known targets each being the vehicle with a number of car-seats installed, and a number of known targets each being the vehicle with a number of child booster seats installed. 
     Clause 50: The method of Clause 1: wherein the venue is a vehicle; wherein at least one classifier is trained or re-trained based on at least one of: TSCI of the vehicle obtained recently when the vehicle is not in a trip, TSCI of the vehicle obtained in a current trip, TSCI of the vehicle obtained in a recent trip, TSCI of the vehicle obtained in an immediate past trip, TSCI of the vehicle obtained in a recent trip when the vehicle is a particular known vehicle, TSCI of the vehicle obtained in a recent trip when the vehicle is in a particular state, TSCI of the vehicle obtained in a recent trip when a particular known driver is driving, TSCI of the vehicle obtained in a recent trip when a particular known passenger is riding in the vehicle, TSCI of the vehicle obtained in a recent trip when a particular known passenger is in at least one of: a particular position, a particular posture, a particular movement, and a particular state, in the vehicle. TSCI of the vehicle obtained in a recent trip when a particular group of known passengers are riding in the vehicle, and TSCI of the vehicle obtained in a recent trip when a particular group of seats are occupied in the vehicle. 
     Clause 51: The method of Clause 27: wherein the at least one classifier is applied within a time window around a moment when the driver door is opened and closed. 
     Clause 52: The method of Clause 27: wherein the at least one classifier is applied within a time window around a moment when the vehicle engine is started. 
     Clause 53: The method of Clause 27: wherein the at least one classifier is applied within a time window around a moment when the vehicle engine is stopped. 
     Clause 54: The method of Clause 27: wherein the at least one classifier is applied while the vehicle is in motion. 
     Clause 55: The method of Clause 27: wherein the at least one classifier is applied when a button of the vehicle is pressed. 
     Clause 56: The method of Clause 27: wherein the at least one classifier is applied upon receiving a control signal. 
     Clause 57: The method of Clause 27, further comprising: adjusting at least one component of the vehicle based on the known passenger. 
     Clause 58: The method of Clause 27, further comprising: adjusting at least one component of the vehicle based on a preference or a previous setting or a condition or a characteristics of the known passenger. 
     Clause 59: The method of Clause 27, further comprising: adjusting a driver seat setting of the vehicle based on a preference or a previous setting or a condition or a characteristics associated with the known passenger. 
     Clause 60: The method of Clause 27, further comprising: adjusting a seat setting of the vehicle based on a preference or a previous setting or a condition or a characteristics of the known passenger. 
     Clause 61: The method of Clause 27, further comprising: adjusting a driver seat setting of the vehicle based on a preference or a previous setting or a condition or a characteristics of a known driver, wherein the recognized passenger is the known driver. 
     Clause 62: The method of Clause 27, further comprising: adjusting an entertainment system setting of the vehicle based on a preference or a previous setting or a condition or a characteristics of the known passenger. 
     Clause 63: The method of Clause 27, further comprising: adjusting an air conditioning system setting of the vehicle based on a preference or a previous setting or a condition or a characteristics of the known passenger. 
     Clause 64: The method of Clause 27, further comprising: adjusting a vehicle subsystem setting of the vehicle based on a preference or a previous setting or a condition or a characteristics of the known passenger. 
     Clause 65: The method of Clause 32 or Clause 33 or Clause 34 or Clause 35, further comprising: adjusting a vehicle subsystem setting of the vehicle based on a preference or a previous setting or a condition or a characteristics of two passenger. 
     Clause 66: The method of Clause 36 or Clause 37, further comprising: adjusting a vehicle subsystem setting of the vehicle based on a preference or a previous setting or a condition or a characteristics of the first number of passengers. 
     Clause 67: The method of Clause 1: wherein N1 is equal to 1 such that there is no channel-hopping over time. 
     Clause 68: The method of Clause 1: wherein N1 is equal to 1 at least for a period of time such that there is no channel-hopping during the period of time. 
     In various embodiments of the present teaching, monitoring a rhythmic motion like breathing may be performed according to the following clauses. 
     Clause A1: A method/software/apparatus/system of a rhythmic motion monitoring system, comprising: obtaining a number, N1, of time series of channel information (CI) of a wireless multipath channel of a venue using a processor, a memory communicatively coupled with the processor and a set of instructions stored in the memory, wherein the N1 time series of CI (TSCI) are extracted from a wireless signal transmitted between a Type 1 heterogeneous wireless device (wireless transmitter) with at least one antenna and a Type 2 heterogeneous wireless device (wireless receiver) with at least one antenna in the venue through the wireless multipath channel, wherein each of the N1 TSCI is associated with an antenna of the Type 1 device and an antenna of the Type 2 device, wherein each CI has N2 components such that each TSCI can is decomposed into N2 time series of CIC (TSCIC), each TSCIC comprising a particular component of all the CI of the TSCI, wherein the wireless multipath channel is impacted by a rhythmic motion of an object in the venue; and monitoring the rhythmic motion of the object based on the N1*N2 TSCIC, and triggering a response action based on the monitoring of the rhythmic motion of the object. 
     Clause A2: The method/apparatus/system of the rhythmic motion monitoring system of clause A1: wherein each CI to comprise at least one of: N2 frequency-domain components, and N2 time-domain components, wherein each CI is associated with a time stamp. 
     Clause A3: The method/apparatus/system of the rhythmic motion monitoring system of clause A2: wherein a frequency transform is applied to each CI with N2 time-domain components to transform it to another CI with N2 frequency-domain components. 
     Clause A4: The method/apparatus/system of the rhythmic motion monitoring system of clause A2: wherein an inverse frequency transform is applied to each CI with N2 frequency-domain components to transform it to another CI with N2 time-domain components. 
     Clause A5: The method/apparatus/system of the rhythmic motion monitoring system of clause A2, further comprising: re-sampling the CI to ensure that the CI are uniformly sampled (time stamp evenly spaced in time). 
     Clause A6: The method/apparatus/system of the rhythmic motion monitoring system of clause A1, further comprising: segmenting each TSCI into overlapping segments of CI, each overlapping segment comprising CI with time stamp in a sliding time window, wherein each overlapping segment is associated with a time stamp; monitoring the rhythmic motion of the object in each overlapping segment. 
     Clause A7: The method/apparatus/system of the rhythmic motion monitoring system of clause A1, further comprising: segmenting each TSCIC into overlapping segments of CIC, each segment comprising CIC with time stamp in a sliding time window; monitoring the rhythmic motion of the object based on the N1*N2 TSCIC in each overlapping segment. 
     Clause A8: The method/apparatus/system of the rhythmic motion monitoring system of clause A7, further comprising: computing a short-time transformation (STT) of each of the N1*N2 TSCIC in each overlapping segment, wherein the STT to comprise at least one of: autocorrelation function, cross-correlation function, auto-covariance function, cross-covariance function, linear transform applied to a limited time period, orthogonal transform, inverse transform, power-of-2 transform, sparse transform, graph-based transform, graph signal processing, fast transform, a transform combined with zero padding, Fourier transform, discrete Fourier transform, discrete time Fourier transform, discrete Fourier transform, wavelet transform, Laplace transform. Hilbert transform, Hadamard transform, slant transform, trigonometric transform, sine transform, cosine transform, another transform, spectrum, spectrum magnitude, spectrum phase, spectrum warping, polynomial warping, square warping, square-root warping, harmonic product spectrum (HPS), sub-harmonic summation (SHS), subharmonic-to-harmonic ratio (SHR), harmonic sieve (HS), average magnitude difference function (AMDF), average squared difference function (ASDF), cepstrum (CEP), average peak-to-valley distance (APVD), sawtooth-waveform inspired pitch estimator (SWIPE), harmonics weighting, harmonics limitation, harmonic discarding, frequency scale warping, frequency emphasis, time scale warping, temporal emphasis, windowing, preprocessing, postprocessing, an operation, a function of operands, filtering, linear filtering, nonlinear filtering, lowpass filtering, bandpass filtering, highpass filtering, median filtering, rank filtering, quartile filtering, percentile filtering, mode filtering, finite impulse response (FIR) filtering, infinite impulse response (IIR) filtering, moving average (MA) filtering, autoregressive (AR) filtering, autoregressive moving averaging (ARMA) filtering, selective filtering, adaptive filtering, folding, grouping, energy computation, interpolation, decimation, subsampling, upsampling, resampling, cyclic padding, padding, zero padding, sorting, thresholding, soft thresholding, hard thresholding, clipping, soft clipping, time correction, time base correction, phase correction, magnitude correction, phase cleaning, magnitude cleaning, matched filtering, Kalman filtering, particle filter, enhancement, restoration, denoising, smoothing, signal conditioning, intrapolation, extrapolation, importance sampling, Monte Carlo sampling, compressive sensing, representing, merging, combining, splitting, scrambling, error protection, forward error correction, spectral analysis, linear transform, nonlinear transform, frequency transform, inverse frequency transform, Fourier transform, wavelet transform, Laplace transform, Hilbert transform, Hadamard transform, trigonometric transform, sine transform, cosine transform, power-of-2 transform, sparse transform, graph-based transform, graph signal processing, fast transform, a transform combined with zero padding, feature extraction, decomposition, projection, orthogonal projection, non-orthogonal projection, over-complete projection, eigen-decomposition, singular value decomposition (SVD), principle component analysis (PCA), independent component analysis (ICA), first derivative, second order derivative, high order derivative, convolution, multiplication, division, addition, subtraction, integration, maximization, minimization, local maximization, local minimization, optimization of a cost function, vector addition, vector subtraction, vector multiplication, vector division, inverse, norm, distance, similarity score computation, neural network, recognition, labeling, training, clustering, machine learning, supervised learning, unsupervised learning, semi-supervised learning, comparison with another TSCI, quantization, vector quantization, matching pursuit, compression, encryption, coding, storing, transmitting, normalization, temporal normalization, frequency domain normalization, classification, clustering, labeling, tagging, learning, detection, estimation, learning network, mapping, remapping, expansion, storing, retrieving, transmitting, receiving, representing, merging, combining, splitting, tracking, monitoring, time varying processing, conditioning averaging, weighted averaging, arithmetic mean, geometric mean, harmonic mean, weighted mean, trimmed mean, median, mode, averaging over selected frequency, averaging over antenna links, logical operation, permutation, combination, sorting, AND, OR, XOR, union, intersection, another operation, and another transformation; monitoring the rhythmic motion of the object based on STT of the N1*N2 TSCIC in each overlapping segment. 
     Clause A9: The method/apparatus/system of the rhythmic motion monitoring system of clause A7, further comprising: adjusting the length of the overlapping segments over time based on a precision requirement of the frequency of the rhythmic motion. 
     Clause A10: The method/apparatus/system of the rhythmic motion monitoring system of clause A7, further comprising: adjusting the sampling time of the CI before the short-time frequency transform such that the CI and CIC are uniformly sampled such that the time stamps of the CI in each TSCI and the CIC in each TSCIC are uniformly spaced in time. 
     Clause A11: The method/apparatus/system of the rhythmic motion monitoring system of clause A10: wherein the sampling time of a CI is adjusted by interpolating a respective re-sampled CI at a desirable time stamp based on the CI and neighboring CI. 
     Clause A12: The method/apparatus/system of the rhythmic motion monitoring system of clause A10: wherein the sampling time of a CIC is adjusted by interpolating a respective re-sampled CIC at a desirable time stamp based on the CIC and neighboring CIC. 
     Clause A13: The method/apparatus/system of the rhythmic motion monitoring system of clause A1, further comprising: monitoring the rhythmic motion of the object by computing at least one analytics associated with the rhythmic motion of the object based on at least one of: the N1 TSCI and the N1*N2 TSCIC, wherein the at least one analytics to comprise at least one of: a frequency, a period, a periodicity parameter, a rhythm, an intensity, a phase, a musical note, a pitch, an expression with a rhythm, a musical rhythm, a punctuated rhythm, a beat, a pace, a walking rhythm, an exercise rhythm, a sports rhythm, a vibration parameter, an oscillation parameter, a pulsation parameter, a relaxing parameter, a motor parameter, an impulsive rhythm, an explosive rhythm, a dominant rhythm, a foreground rhythm, a background rhythm, a random rhythm, a chaotic rhythm, a stochastic rhythm, a breathing rate, a breathing period, a heart rate, a vital sign, a change of the breathing rate, a change of the heart rate, a change of the vital sign, a count, a count associated the rhythmic motion of the object, a count of sources of rhythmic motion, a count of the object and other objects, a count of people, a change in the count, a tag, a tag associated with the rhythmic motion, a tag associated with the object, an activity associated with the rhythmic motion, a change in the tag, a location, a location associated with the rhythmic motion, a location associated with the object, a change in the location, a time, a timing, a starting time/timing, a stopping time/timing, a pausing time/timing, an interruption time/timing, a repeating/hourly/daily/weekly/monthly/yearly activity pattern, a repeating timing, movement pattern, a repeating trend, a daily activity associated with the rhythmic motion, a daily activity, a spontaneous activity, a variation, a variation of the frequency, a variation of pitch, prosody, a variation of the period, a variation of rhythm, a variation of intensity, a variation of phase, a variation of parameter, a relationship between two rhythms, a cause-and-effect between two rhythms, and another rhythm parameter. 
     Clause A14: The method/apparatus/system of the rhythmic motion monitoring system of clause A1, further comprising: monitoring the rhythmic motion of the object by computing at least one analytics associated with the rhythmic motion of the object based on a processing of at least one of: the N1 TSCI and the N1*N2 TSCIC, wherein the processing to comprise at least one of: preprocessing, postprocessing, an operation, a function of operands, filtering, linear filtering, nonlinear filtering, lowpass filtering, bandpass filtering, highpass filtering, median filtering, rank filtering, quartile filtering, percentile filtering, mode filtering, finite impulse response (FIR) filtering, infinite impulse response (IIR) filtering, moving average (MA) filtering, autoregressive (AR) filtering, autoregressive moving averaging (ARMA) filtering, selective filtering, adaptive filtering, folding, grouping, energy computation, interpolation, decimation, subsampling, upsampling, resampling, cyclic padding, padding, zero padding, sorting, thresholding, soft thresholding, hard thresholding, clipping, soft clipping, time correction, time base correction, phase correction, magnitude correction, phase cleaning, magnitude cleaning, matched filtering, Kalman filtering, particle filter, enhancement, restoration, denoising, smoothing, signal conditioning, intrapolation, extrapolation, importance sampling, Monte Carlo sampling, compressive sensing, representing, merging, combining, splitting, scrambling, error protection, forward error correction, spectral analysis, linear transform, nonlinear transform, frequency transform, inverse frequency transform, Fourier transform, wavelet transform, Laplace transform, Hilbert transform, Hadamard transform, trigonometric transform, sine transform, cosine transform, power-of-2 transform, sparse transform, graph-based transform, graph signal processing, fast transform, a transform combined with zero padding, feature extraction, decomposition, projection, orthogonal projection, non-orthogonal projection, over-complete projection, eigen-decomposition, singular value decomposition (SVD), principle component analysis (PCA), independent component analysis (ICA), first derivative, second order derivative, high order derivative, convolution, multiplication, division, addition, subtraction, integration, maximization, minimization, local maximization, local minimization, optimization of a cost function, vector addition, vector subtraction, vector multiplication, vector division, inverse, norm, distance, similarity score computation, neural network, recognition, labeling, training, clustering, machine learning, supervised learning, unsupervised learning, semi-supervised learning, comparison with another TSCI, quantization, vector quantization, matching pursuit, compression, encryption, coding, storing, transmitting, normalization, temporal normalization, frequency domain normalization, classification, clustering, labeling, tagging, learning, detection, estimation, learning network, mapping, remapping, expansion, storing, retrieving, transmitting, receiving, representing, merging, combining, splitting, tracking, monitoring, time varying processing, conditioning averaging, weighted averaging, arithmetic mean, geometric mean, harmonic mean, weighted mean, trimmed mean, median, mode, averaging over selected frequency, averaging over antenna links, logical operation, permutation, combination, sorting, AND, OR, XOR, union, intersection, doing nothing, and another operation. 
     Clause A15: The method/apparatus/system of the rhythmic motion monitoring system of clause A8, further comprising: monitoring the rhythmic motion of the object by computing at least one analytics associated with the rhythmic motion of the object based on STT of the N1*N2 TSCIC, wherein the at least one analytics to comprise at least one of: a frequency, a period, a periodicity parameter, a rhythm, an intensity, a phase, a musical note, a pitch, an expression with a rhythm, a musical rhythm, a punctuated rhythm, a beat, a pace, a walking rhythm, an exercise rhythm, a sports rhythm, a vibration parameter, an oscillation parameter, a pulsation parameter, a relaxing parameter, a motor parameter, an impulsive rhythm, an explosive rhythm, a dominant rhythm, a foreground rhythm, a background rhythm, a random rhythm, a chaotic rhythm, a stochastic rhythm, a breathing rate, a breathing period, a heart rate, a vital sign, a change of the breathing rate, a change of the heart rate, a change of the vital sign, a count, a count associated the rhythmic motion of the object, a count of sources of rhythmic motion, a count of the object and other objects, a count of people, a charge in the count, a tag, a tag associated with the rhythmic motion, a tag associated with the object, an activity associated with the rhythmic motion, a change in the tag, a location, a location associated with the rhythmic motion, a location associated with the object, a change in the location, a time, a timing, a starting time/timing, a stopping time/timing, a pausing time/timing, an interruption time/timing, a repeating/hourly/daily/weekly/monthly/yearly activity pattern, a repeating timing, movement pattern, a repeating trend, a daily activity associated with the rhythmic motion, a daily activity, a spontaneous activity, a variation, a variation of the frequency, a variation of pitch, prosody, a variation of the period, a variation of rhythm, a variation of intensity, a variation of phase, a variation of parameter, a relationship between two rhythms, a cause-and-effect between two rhythms, and another rhythm parameter. 
     Clause A16: The method/apparatus/system of the rhythmic motion monitoring system of clause A15, further comprising: computing a combined analytics as a function of N1*N2 analytics, each analytics associated with a respective TSCIC, wherein the function to comprise at least one of: scalar function, vector function, discrete function, continuous function, polynomial function, characteristics, feature, magnitude, phase, exponential function, logarithmic function, trigonometric function, transcendental function, logical function, linear function, algebraic function, nonlinear function, piecewise linear function, real function, complex function, vector-valued function, inverse function, derivative of function, integration of function, circular function, function of another function, one-to-one function, one-to-many function, many-to-one function, many-to-many function, zero crossing, absolute function, indicator function, mean, mode, median, range, statistics, variance, arithmetic mean, geometric mean, harmonic mean, weighted mean, trimmed mean, conditional mean, percentile, maximum, minimum, square, cube, root, power, sine, cosine, tangent, cotangent, secant, cosecant, elliptical function, parabolic function, hyperbolic function, game function, zeta function, absolute value, thresholding, limiting function, floor function, rounding function, sign function, quantization, piecewise constant function, composite function, function of function, time function processed with an operation (e.g. filtering), probabilistic function, stochastic function, random function, ergodic function, stationary function, deterministic function, periodic function, transformation, frequency transform, inverse frequency transform, discrete time transform, Laplace transform, Hilbert transform, sine transform, cosine transform, triangular transform, wavelet transform, integer transform, power-of-2 transform, sparse transform, projection, decomposition, principle component analysis (PCA), independent component analysis (ICA), neural network, feature extraction, moving function, function of moving window of neighboring items of time series, filtering function, convolution, mean function, variance function, statistical function, short-time transform, discrete transform, discrete Fourier transform, discrete cosine transform, discrete sine transform, Hadamard transform, eigen-decomposition, eigenvalue, singular value decomposition (SVD), singular value, orthogonal decomposition, matching pursuit, sparse transform, sparse approximation, any decomposition, graph-based processing, graph-based transform, graph signal processing, classification, labeling, learning, machine learning, detection, estimation, feature extraction, learning network, feature extraction, denoising, signal enhancement, coding, encryption, mapping, remapping, vector quantization, lowpass filtering, highpass filtering, bandpass filtering, matched filtering, Kalman filtering, preprocessing, postprocessing, particle filter, FIR filtering, IIR filtering, autoregressive (AR) filtering, adaptive filtering, first order derivative, high order derivative, integration, smoothing, median filtering, mode filtering, sampling, random sampling, resampling function, downsampling, upsampling, interpolation, extrapolation, importance sampling, Monte Carlo sampling, compressive sensing, statistics, short term statistics, long term statistics, mean, variance, autocorrelation function, cross correlation, moment generating function, time averaging, weighted averaging, special function, transcendental function, Bessel function, error function, complementary error function. Beta function, Gamma function, integral function, Gaussian function, Poisson function, and another function. 
     Clause A17: The method/apparatus/system of the rhythmic motion monitoring system of clause A8, further comprising: computing a number of intermediate STT (ISTT) based on the STT of the N1*N2 TSCIC; monitoring the rhythmic motion of the object based on the number of ISTT. 
     Clause A18: The method/apparatus/system of the rhythmic motion monitoring system of clause A17, further comprising: computing N1 ISTT, each ISTT based on N2 TSCIC; for each of the N1 TSCI, the ISTT associated with the respective TSCI is a function of the STT of the respective N2 TSCIC in the overlapping segment, each of the respective N2 TSCIC being associated with one of the N2 CIC, wherein the function to comprise at least one of: a pointwise function, a sliding function, a localized function, a sliding localized function, a section-by-section function, a pitch estimation function, a hybrid function, scalar function, vector function, discrete function, continuous function, polynomial function, characteristics, feature, magnitude, phase, exponential function, logarithmic function, trigonometric function, transcendental function, logical function, linear function, algebraic function, nonlinear function, piecewise linear function, real function, complex function, vector-valued function, inverse function, derivative of function, integration of function, circular function, function of another function, one-to-one function, one-to-many function, many-to-one function, many-to-many function, zero crossing, absolute function, indicator function, mean, mode, median, range, statistics, variance, arithmetic mean, geometric mean, harmonic mean, weighted mean, trimmed mean, conditional mean, percentile, maximum, minimum, square, cube, root, power, sine, cosine, tangent, cotangent, secant, cosecant, elliptical function, parabolic function, hyperbolic function, game function, zeta function, absolute value, thresholding, limiting function, floor function, rounding function, sign function, quantization, piecewise constant function, composite function, function of function, time function processed with an operation (e.g. filtering), probabilistic function, stochastic function, random function, ergodic function, stationary function, deterministic function, periodic function, transformation, frequency transform, inverse frequency transform, discrete time transform, Laplace transform, Hilbert transform, sine transform, cosine transform, triangular transform, wavelet transform, integer transform, power-of-2 transform, sparse transform, projection, decomposition, principle component analysis (PCA), independent component analysis (ICA), neural network, feature extraction, moving function, function of moving window of neighboring items of time series, filtering function, convolution, mean function, variance function, statistical function, short-time transform, discrete transform, discrete Fourier transform, discrete cosine transform, discrete sine transform, Hadamard transform, eigen-decomposition, eigenvalue, singular value decomposition (SVD), singular value, orthogonal decomposition, matching pursuit, sparse transform, sparse approximation, any decomposition, graph-based processing, graph-based transform, graph signal processing, classification, labeling, learning, machine learning, detection, estimation, feature extraction, learning network, feature extraction, denoising, signal enhancement, coding, encryption, mapping, remapping, vector quantization, lowpass filtering, highpass filtering, bandpass filtering, matched filtering, Kalman filtering, preprocessing, postprocessing, particle filter, FIR filtering, IIR filtering, autoregressive (AR) filtering, adaptive filtering, first order derivative, high order derivative, integration, smoothing, median filtering, mode filtering, sampling, random sampling, resampling function, downsampling, upsampling, interpolation, extrapolation, importance sampling, Monte Carlo sampling, compressive sensing, statistics, short term statistics, long term statistics, mean, variance, autocorrelation function, cross correlation, moment generating function, time averaging, weighted averaging, special function, transcendental function, Bessel function, error function, complementary error function, Beta function, Gamma function, integral function, Gaussian function, Poisson function, and another function. 
     Clause A19: The method/apparatus/system of the rhythmic motion monitoring system of clause A17, further comprising: computing N2 ISTT, each ISTT based on N1 TSCIC; for each of the N2 CIC, the ISTT associated with the respective CIC is a function of the STT of the respective N1 TSCIC in the overlapping segment, each of the respective N1 TSCIC being associated with one of the N1 TSCI, wherein the function to comprise at least one of: a pointwise function, a sliding function, a localized function, a sliding localized function, a section-by-section function, a pitch estimation function, a hybrid function, scalar function, vector function, discrete function, continuous function, polynomial function, characteristics, feature, magnitude, phase, exponential function, logarithmic function, trigonometric function, transcendental function, logical function, linear function, algebraic function, nonlinear function, piecewise linear function, real function, complex function, vector-valued function, inverse function, derivative of function, integration of function, circular function, function of another function, one-to-one function, one-to-many function, many-to-one function, many-to-many function, zero crossing, absolute function, indicator function, mean, mode, median, range, statistics, variance, arithmetic mean, geometric mean, harmonic mean, weighted mean, trimmed mean, conditional mean, percentile, maximum, minimum, square, cube, root, power, sine, cosine, tangent, cotangent, secant, cosecant, elliptical function, parabolic function, hyperbolic function, game function, zeta function, absolute value, thresholding, limiting function, floor function, rounding function, sign function, quantization, piecewise constant function, composite function, function of function, time function processed with an operation (e.g. filtering), probabilistic function, stochastic function, random function, ergodic function, stationary function, deterministic function, periodic function, transformation, frequency transform, inverse frequency transform, discrete time transform, Laplace transform, Hilbert transform, sine transform, cosine transform, triangular transform, wavelet transform, integer transform, power-of-2 transform, sparse transform, projection, decomposition, principle component analysis (PCA), independent component analysis (ICA), neural network, feature extraction, moving function, function of moving window of neighboring items of time series, filtering function, convolution, mean function, variance function, statistical function, short-time transform, discrete transform, discrete Fourier transform, discrete cosine transform, discrete sine transform, Hadamard transform, eigen-decomposition, eigenvalue, singular value decomposition (SVD), singular value, orthogonal decomposition, matching pursuit, sparse transform, sparse approximation, any decomposition, graph-based processing, graph-based transform, graph signal processing, classification, labeling, learning, machine learning, detection, estimation, feature extraction, learning network, feature extraction, denoising, signal enhancement, coding, encryption, mapping, remapping, vector quantization, lowpass filtering, highpass filtering, bandpass filtering, matched filtering, Kalman filtering, preprocessing, postprocessing, particle filter, FIR filtering, IIR filtering, autoregressive (AR) filtering, adaptive filtering, first order derivative, high order derivative, integration, smoothing, median filtering, mode filtering, sampling, random sampling, resampling function, downsampling, upsampling, interpolation, extrapolation, importance sampling, Monte Carlo sampling, compressive sensing, statistics, short term statistics, long term statistics, mean, variance, autocorrelation function, cross correlation, moment generating function, time averaging, weighted averaging, special function, transcendental function, Bessel function, error function, complementary error function, Beta function, Gamma function, integral function, Gaussian function, Poisson function, and another function. 
     Clause A20: The method/apparatus/system of the rhythmic motion monitoring system of clause A17, further comprising: computing a combined STT (CSTT) based on the number of ISTT; monitoring the rhythmic motion of the object based on the CSTT. 
     Clause A21: The method/apparatus/system of the rhythmic motion monitoring system of clause A17, further comprising: computing a combined STT (CSTT) as a function of the number of ISTT: monitoring the rhythmic motion of the object based on the CSTT, wherein the function to comprise at least one of: scalar function, vector function, discrete function, continuous function, polynomial function, characteristics, feature, magnitude, phase, exponential function, logarithmic function, trigonometric function, transcendental function, logical function, linear function, algebraic function, nonlinear function, piecewise linear function, real function, complex function, vector-valued function, inverse function, derivative of function, integration of function, circular function, function of another function, one-to-one function, one-to-many function, many-to-one function, many-to-many function, zero crossing, absolute function, indicator function, mean, mode, median, range, statistics, variance, arithmetic mean, geometric mean, harmonic mean, weighted mean, trimmed mean, conditional mean, percentile, maximum, minimum, square, cube, root, power, sine, cosine, tangent, cotangent, secant, cosecant, elliptical function, parabolic function, hyperbolic function, game function, zeta function, absolute value, thresholding, limiting function, floor function, rounding function, sign function, quantization, piecewise constant function, composite function, function of function, time function processed with an operation (e.g. filtering), probabilistic function, stochastic function, random function, ergodic function, stationary function, deterministic function, periodic function, transformation, frequency transform, inverse frequency transform, discrete time transform, Laplace transform, Hilbert transform, sine transform, cosine transform, triangular transform, wavelet transform, integer transform, power-of-2 transform, sparse transform, projection, decomposition, principle component analysis (PCA), independent component analysis (ICA), neural network, feature extraction, moving function, function of moving window of neighboring items of time series, filtering function, convolution, mean function, variance function, statistical function, short-time transform, discrete transform, discrete Fourier transform, discrete cosine transform, discrete sine transform, Hadamard transform, eigen-decomposition, eigenvalue, singular value decomposition (SVD), singular value, orthogonal decomposition, matching pursuit, sparse transform, sparse approximation, any decomposition, graph-based processing, graph-based transform, graph signal processing, classification, labeling, learning, machine learning, detection, estimation, feature extraction, learning network, feature extraction, denoising, signal enhancement, coding, encryption, mapping, remapping, vector quantization, lowpass filtering, highpass filtering, bandpass filtering, matched filtering, Kalman filtering, preprocessing, postprocessing, particle filter, FIR filtering, IIR filtering, autoregressive (AR) filtering, adaptive filtering, first order derivative, high order derivative, integration, smoothing, median filtering, mode filtering, sampling, random sampling, resampling function, downsampling, upsampling, interpolation, extrapolation, importance sampling, Monte Carlo sampling, compressive sensing, statistics, short term statistics, long term statistics, mean, variance, autocorrelation function, cross correlation, moment generating function, time averaging, weighted averaging, special function, transcendental function, Bessel function, error function, complementary error function. Beta function, Gamma function, integral function, Gaussian function, Poisson function, and another function. 
     Clause A22: The method/apparatus/system of the rhythmic motion monitoring system of clause A17, further comprising: monitoring the rhythmic motion of the object by computing at least one analytics based on the number of ISTT. 
     Clause A23: The method/apparatus/system of the rhythmic motion monitoring system of clause A20, further comprising: monitoring the rhythmic motion of the object by computing at least one analytics based on at least one of: the CSTT and the number of ISTT. 
     Clause A24: The method/apparatus/system of the rhythmic motion monitoring system of one of clause A13 to clause A24 (i.e. one of the 10 claims) further comprising: wherein each analytics is associated with a time stamp, a time window associated with the time stamp, the N1 TSCI restricted to the time window and the N1*N2 TSCIC restricted to the time window; grouping a first analytics with a first time stamp and a second analytics with a second time stamp, wherein the second time stamp is adjacent to the first time stamp. 
     Clause A25: The method/apparatus/system of the rhythmic motion monitoring system of clause A24 further comprising: grouping the first analytics and the second analytics based on a cost associated with the first analytics and the second analytics. 
     Clause A26: The method/apparatus/system of the rhythmic motion monitoring system of clause A24 further comprising: grouping the first analytics and the second analytics based on a similarity score between the first analytics and the second analytics. 
     Clause A27: The method/apparatus/system of the rhythmic motion monitoring system of clause A24 further comprising: grouping the first analytics and the second analytics based on at least one of: a similarity score between the first analytics and the second analytics, and a state transition cost between a first state associated with the first analytics and a second state associated with the second analytics. 
     Clause A28: The method/apparatus/system of the rhythmic motion monitoring system of clause A24 further comprising: grouping a number of analytics with different time stamps into a time trace of analytics. 
     Clause A29: The method/apparatus/system of the rhythmic motion monitoring system of clause A28 further comprising: adding a number of analytics with different time stamps into a time trace of analytics by iteratively adding a later analytics to an existing time trace of analytics. 
     Clause A30: The method/apparatus/system of the rhythmic motion monitoring system of clause A28 further comprising: grouping the number of analytics into the time trace of analytics based on a cost function. 
     Clause A31: The method/apparatus/system of the rhythmic motion monitoring system of clause A30 further comprising: grouping the number of analytics into the time trace of analytics based on a cost function and an initial condition. 
     Clause A32: The method/apparatus/system of the rhythmic motion monitoring system of clause A30 further comprising: grouping the number of analytics into the time trace of analytics based on a cost function and an ending condition. 
     Clause A33: The method/apparatus/system of the rhythmic motion monitoring system of clause A30 further comprising: grouping the number of analytics into the time trace of analytics based on a cost function and a boundary condition of the analytics. 
     Clause A34: The method/apparatus/system of the rhythmic motion monitoring system of clause A28: wherein the cost function is based on at least one of: a similarity score between two analytics, a state transition cost between a first state associated with a first analytics and a second state associated with a second analytics, and a state transition cost based on the first state associated with the first analytics and a state history associated with the first analytics. 
     Clause A35: The method/apparatus/system of the rhythmic motion monitoring system of clause A28: wherein the cost function favors consecutive analytics with large similarity and penalizes consecutive analytics with small similarity. 
     Clause A36: The method/apparatus/system of the rhythmic motion monitoring system of clause A28: wherein the cost function favors consecutive analytics with no state change and penalizes consecutive analytics with state change. 
     Clause A37: The method/apparatus/system of the rhythmic motion monitoring system of clause A28 further comprising: computing at least one time trace of analytics. 
     Clause A38: The method/apparatus/system of the rhythmic motion monitoring system of clause A37 further comprising: computing a count of the object and other objects based on the at least one time trace of analytics. 
     Clause A39: The method/apparatus/system of the rhythmic motion monitoring system of clause A38 further comprising: computing a count of the object and other objects based on a count of the at least one time trace of analytics. 
     Clause A40: The method/apparatus/system of the rhythmic motion monitoring system of clause A38 further comprising: computing a count of the object and other objects based on a count of the at least one time trace of analytics that satisfies a condition. 
     Clause A41: The method/apparatus/system of the rhythmic motion monitoring system of clause A38 further comprising: computing a count based on a count of the at least one time trace of analytics. 
     Clause A42: The method/apparatus/system of the rhythmic motion monitoring system of clause A1: wherein the response action to comprise at least one of: presenting at least one analytics associated with the rhythmic motion of the object computed based on at least one of: the TSIC, and the TSCIC; presenting an analytics of the object; creating a presentation based on the rhythmic motion of the object; transmitting an analytics of the rhythmic motion of the object to a user device; transmitting a message to the user device. 
     In various embodiments of the present teaching, monitoring and tracking a dynamic analytics trace may be performed according to the following clauses. 
     Clause B1: A method/software/apparatus/system of an analytics trace finding system, comprising: obtaining at least one time series of channel information (CI) of a wireless multipath channel of a venue using a processor, a memory communicatively coupled with the processor and a set of instructions stored in the memory, wherein the at least one time series of CI (TSCI) is extracted from a wireless signal transmitted between a Type 1 heterogeneous wireless device (wireless transmitter) and a Type 2 heterogeneous wireless device (wireless receiver) in the venue through the wireless multipath channel; computing a first number of analytics associated with a first time stamp based on the at least one TSCI; computing a second number of analytics associated with a second time stamp based on the at least one TSCI; grouping a first analytics with the first time stamp and a second analytics with the second time stamp; and triggering a response action based on the grouping. 
     Clause B2: The method/software/apparatus/system of the analytics trace finding system of clause B1, further comprising: grouping the first analytics and the second analytics based on a cost associated with the first analytics and the second analytics. 
     Clause B3: The method/software/apparatus/system of the analytics trace finding system of clause B1, further comprising: grouping the first analytics and the second analytics based on a similarity score associated with the first analytics and the second analytics. 
     Clause B4: The method/software/apparatus/system of the analytics trace finding system of clause B1, further comprising: grouping the first analytics and the second analytics based on at least one of: a similarity score between the first analytics and the second analytics, and a state transition cost between a first state associated with the first analytics and a second state associated with the second analytics. 
     Clause B5: A method/software/apparatus/system of an analytics trace finding system, further comprising: obtaining at least one time series of channel information (CI) of a wireless multipath channel of a venue using a processor, a memory communicatively coupled with the processor and a set of instructions stored in the memory, wherein the at least one time series of CI (TSCI) is extracted from a wireless signal transmitted between a Type 1 heterogeneous wireless device (wireless transmitter) and a Type 2 heterogeneous wireless device (wireless receiver) in the venue through the wireless multipath channel; for each of a series of time stamps, computing a respective number of analytics for the time stamp based on the at least one TSCI; computing at least one analytics trace based on the analytics, each analytics trace being a time series of analytics (TSA) within a respective time segment, wherein the TSA has one analytics for each time stamp in the time segment. 
     Clause B6: The method/software/apparatus/system of the analytics trace finding system of clause B5, further comprising: computing each analytics trace based on a cost associated with the TSA. 
     Clause B7: The method/software/apparatus/system of the analytics trace finding system of clause B6: wherein the cost to comprise at least one of: a similarity score, and a state transition cost. 
     Clause B8: The method/software/apparatus/system of the analytics trace finding system of clause B6: wherein the cost to comprise at least one of: a similarity score between two analytics, a state transition cost between a first state associated with a first analytics and a second state associated with a second analytics, a state transition cost based on the first state associated with the first analytics and a state history associated with the first analytics, and a cumulative cost over the respective time segment. 
     Clause B9: The method/software/apparatus/system of the analytics trace finding system of clause B6: wherein the cost favors consecutive analytics with large similarity and penalizes consecutive analytics with small similarity. 
     Clause B10: The method/software/apparatus/system of the analytics trace finding system of clause B6: wherein the cost favors consecutive analytics with no state change and penalizes consecutive analytics with state change. 
     Clause B11: The method/software/apparatus/system of the analytics trace finding system of clause B5, further comprising: computing each analytics trace based on at least one of: an initial condition, an ending condition, a boundary condition, and another condition. 
     Clause B12: The method/software/apparatus/system of the analytics trace finding system of clause B5: computing each analytics trace based on at least one of: an initial condition associated with an initial portion of the respective time segment, an ending condition associated with an ending portion of the respective time segment, a condition associated a boundary of the respective time segment, a condition associated with a time of the respective time segment, and another condition. 
     Clause B13: The method/software/apparatus/system of the analytics trace finding system of clause B5, further comprising: adding a new analytics to a current TSA, wherein time stamp associated with the new analytics is later than all time stamps of the current TSA. 
     Clause B14: The method/software/apparatus/system of the analytics trace finding system of clause B5, further comprising: updating a current TSA based on a new analytics, wherein time stamp associated with the new analytics is later than all time stamps of the current TSA. 
     Clause B15: The method/software/apparatus/system of the analytics trace finding system of clause B5, further comprising: determining that an analytics at a time stamp belongs to more than one analytics traces, being in more than one respective TSA. 
     Clause B16: The method/software/apparatus/system of the analytics trace finding system of clause B5, further comprising: computing the at least one analytics trace based on at least one of: brute force searching, fast searching, genetic searching, divide-and-conquer searching, dynamic programming and another algorithm. 
     Clause B17: The method/software/apparatus/system of the analytics trace finding system of clause B5, further comprising: computing at least one cost for at least one candidate analytics trace for at least one candidate time segment, computing the at least one analytics trace based on all the candidate analytics trace and the associated cost. 
     Clause B18: The method/software/apparatus/system of the analytics trace finding system of clause B17, further comprising: identifying a candidate analytics trace as one of the at least one analytics trace when the associated at least one cost satisfies at least one condition. 
     Clause B19: The method/software/apparatus/system of the analytics trace finding system of clause B17: wherein the at least one condition to comprise at least one of: an associated cost is smaller than an upper threshold and larger than a lower threshold, each of the associated at least one cost is smaller than a respective upper threshold and larger than a respective lower threshold, an associated cost is local minimum, a combined cost is minimum, and another condition. 
     Clause B20: The method/software/apparatus/system of the analytics trace finding system of clause B5, further comprising: computing at least one count based on the at least one analytics trace. 
     Clause B21: The method/software/apparatus/system of the analytics trace finding system of clause B5, further comprising: computing at least one count based on a count of the at least one analytics trace. 
     Clause B22: The method/software/apparatus/system of the analytics trace finding system of clause B5, further comprising: computing at least one count based on a count of the at least one analytics trace that satisfied a condition. 
     Clause B23: The method/software/apparatus/system of the analytics trace finding system of clause B5, further comprising: computing at least one count of people in the venue based on the at least one analytics trace. 
     Clause B24: The method/software/apparatus/system of the analytics trace finding system of clause B5, further comprising: computing at least one count of people in the venue based on a count of the at least one analytics trace. 
     Clause B25: The method/software/apparatus/system of the analytics trace finding system of clause B5, further comprising: computing at least one count of people in the venue based on a count of the at least one analytics trace that satisfied a condition. 
     Clause B26: The method/software/apparatus/system of the analytics trace finding system of clause B5, further comprising: computing at least one count of objects in the venue based on the at least one analytics trace. 
     Clause B27: The method/software/apparatus/system of the analytics trace finding system of clause B5, further comprising: computing at least one count of objects in the venue based on a count of the at least one analytics trace. 
     Clause B28: The method/software/apparatus/system of the analytics trace finding system of clause B5, further comprising: computing at least one count of objects in the venue based on a count of the at least one analytics trace that satisfied a condition. 
     Clause B29: The method/software/apparatus/system of the analytics trace finding system of clause B5: wherein the analytics to comprise at least one of: a frequency, a period, a periodicity parameter, a rhythm, an intensity, a phase, a musical note, a pitch, an expression with a rhythm, a musical rhythm, a punctuated rhythm, a beat, a pace, a walking rhythm, an exercise rhythm, a sports rhythm, a vibration parameter, an oscillation parameter, a pulsation parameter, a relaxing parameter, a motor parameter, an impulsive rhythm, an explosive rhythm, a dominant rhythm, a foreground rhythm, a background rhythm, a random rhythm, a chaotic rhythm, a stochastic rhythm, a motion, a rhythmic motion, a breathing rate, a breathing period, a heart rate, a vital sign, a change of the breathing rate, a change of the heart rate, a change of the vital sign, a transient motion, a movement, an activity, a gait, a gesture, a handwriting, a pattern, a trace, a history, a sign of danger, a fall-down, a person, an information of the person, an object, an information of the object, a device, an identity, a count, a count associated a rhythmic motion, a count of sources of rhythmic motion, a count of objects, a count of vehicles, a count of people, a count of pets, a count of babies, a count of juveniles, a count of objects in a certain state, a count of stations in a certain state, a count of booth without occupancy, a change in the count, a scalar, a vector, a change, a rate of change, a derivative, an aggregate, an integration, a sum, a weighted mean, a trimmed mean, a moving average, a filtering, a statistics, a variance, a correlation, a covariance, a cross correlation, a cross covariance, an autocorrelation, a tag, a tag associated with a motion, a tag associated with an object, an activity associated with the rhythmic motion, a change in the tag, a state, an event, an indicator of a state, an indicator of an event, SLEEP, NON-SLEEP, REM, NREM, AWAKE, MOTION, NO-MOTION, BATHROOM-VISIT, a presence/an absence, an emotional state, a movement parameter, a location, a location associated with a map, a location associated with a motion, a location associated with an object, a change in the location, a distance, a displacement, a speed, a velocity, an acceleration, an angle, an angular speed, an angular acceleration, a trajectory, a time, a timing, a starting time/timing, a stopping time/timing, a pausing time/timing, an interruption time/timing, a repeating/hourly/daily/weekly/monthly/yearly activity pattern, a repeating timing, movement pattern, a repeating trend, a daily activity associated with the rhythmic motion, a daily activity, a spontaneous activity, a variation, a variation of the frequency, a variation of pitch, prosody, a variation of the period, a variation of rhythm, a variation of intensity, a variation of phase, a variation of parameter, a relationship between two rhythms, a cause-and-effect between two rhythms, and another rhythm parameter. 
     Clause B30: The method/software/apparatus/system of the analytics trace finding system of clause B5, further comprising: identifying at least one of: an event, a movement, an action, an object based on the at least one analytics trace. 
     Clause B31: The method/software/apparatus/system of the analytics trace finding system of clause B5, further comprising: triggering a response action based on the at least one analytics trace. 
     Clause B32: The method/software/apparatus/system of the analytics trace finding system of clause B5, further comprising: computing at least one count based on the at least one analytics trace; triggering a response action based on at least one of: the at least one analytics trace and the at least one count. 
     In one example, the disclosed system may be used to obtain a quantity of people in a venue with a rich-scattering environment, e.g. an amusement park, a hospital, a room, a building, a bus, an airplane, a cruise ship, a train, etc. The disclosed system may find a trace of motion analytics of people in the venue, based on channel information of a wireless multipath channel impacted by the people&#39;s motion. The trace may be a time trace/time trend, or a location trace/trajectory. For example, the disclosed system may find a trace of breathing rate or heartbeat rate of people in the venue, and determine the quantity of people in the venue based on the trace. 
     In another example, the disclosed system may be used to recognize an identity of a person at a location with a rich-scattering environment, e.g. a door, a gate, a monitored area in a building, etc. For each of a plurality of candidate persons in front of a door, the disclosed system may obtain a rate distribution of rhythmic motion (e.g. breathing, heartbeat) of the candidate person based on a training dataset. When a visitor is at the door, the disclosed system may compute a trace of motion analytics of the visitor, based on channel information of a wireless multipath channel impacted by the visitor&#39;s rhythmic motion. For example, the disclosed system may find a trace of breathing rate or heartbeat rate of the visitor at the door, and determine a likelihood function for the trace to be associated with each respective candidate person in database, based on the rate distribution of rhythmic motion of the respective candidate persons. The disclosed system may recognize the visitor to be a candidate person that maximizes the likelihood function. In one embodiment, if the maximized likelihood is still below a threshold, the disclosed system determines that the visitor is not recognized. 
     In yet another example, the disclosed system may be used to recognize an identity of a person in a car, e.g. whether the person is a particular driver in the database. For example, after a driver enters the car, the entering action of the driver may be related to the driver&#39;s habit and may be used for training a classifier and for driver recognition. For example, some drivers may enter the car and wait. Some drivers may rest hands on steering wheel. Some drivers may wiggle body for a nice comfortable position. Some drivers may put down a coffee. Some drivers may put down a bag. Some drivers may put a smart phone (with map app running) on dash board. Some drivers may press a button on dash board. Some drivers may check and adjust mirror. Some drivers may insert car key. Some drivers may check and work on the phone, such as enter destination on map. Similarly, the car-exiting action of the driver may also be related to the driver&#39;s habit and may be used for training a classifier and for driver recognition. When a person enters or exits a car, the disclosed system can detect a motion and/or posture of the person based on channel information of a wireless multipath channel impacted by the people&#39;s motion and/or posture, and determine whether the person is a driver of the car based on whether the detected motion and/or posture matches a stored motion and/or posture of the driver in the database. 
     The present teaching also discloses processing, compilation, organization, grouping and presentation of time-stamped data for a visual display or other feedback or user-interface (UI) device. Various embodiments of the present teaching are regarding the processing, compilation, organization, grouping and presentation of time-stamped data for a visual display (e.g. computer monitor, smart phone display, tablet, TV, projector, animation, etc.) or other feedback or user-interface (UI) device (e.g. voice presentation via smart phones, computers, tablets, sound-enabled devices, a smart speaker such as Amazon Echo/Alexa, or vibration, or haptic device). 
     In one embodiment, each time-stamped data item may comprise a scalar, a duration, a timing, an ordered pair, an n-tuple, a coordinate, a location, a direction, an angle, an attribute, a description, a trend, a behavior, a motion, a movement, a gesture (e.g. handwriting, hand sign, keystroke, facial expression), a vital sign, a feature, an object, an identification, a characteristics, a phenomenon, an event (e.g. fall-down), a state, a transition, a status, a stage (e.g. sleep stage, awake, REM, NREM, etc.), a relationship, a vector, a matrix, a classification, a detection, a decision, a conclusion, a set, a group, a collection, an element, a subset, and/or any mixture of these. The time stamped data may be associated with one or more time series of channel information (CI). The time-stamped data may comprise one or more analytics obtained/determined/computed based on the one or more time series of CI (e.g. channel state information, or CSI) extracted from a wireless signal transmitted from a Type 1 heterogeneous wireless device to a Type 2 heterogeneous wireless device via a wireless multipath channel of a venue. 
     In one embodiment, a Type 1 device may transmit the wireless signal to multiple Type 2 devices. A Type 2 device may receive multiple wireless signals from multiple Type 1 devices, each wireless signal from a corresponding Type 1 device. A Type 1 device and a Type 2 device may be the same device (i.e. operating like a radar system). A Type 1 device and a Type 2 device may be attached to/in/on/of a machine. The wireless signal may be a series of probe signals. The probe signals may be sent at regular, basically regular, or irregular time intervals. The probe signal may or may not be transmitted with data. The probe signal may be a data packet. Each probe signal when received may be time stamped. 
     In an example, one (or more) Type 1 device and one (or more) Type 2 device may be placed around a bed (or anywhere) to monitor the motion and breathing of one (or more) person lying on the bed in the bedroom. For a bed with two people sleeping, a Type 1 device may be placed on one end (e.g. the left) and another Type 1 device on another end (e.g. the right) to monitor the motion and breathing of two people simultaneously. The Type 2 device may be placed near the bed (e.g. at the front, at the back, underneath the mattress/bed, above the bed), or at another location in the house. 
     In another example, the Type 1 device(s) and Type 2 device(s) may be placed at various places (e.g. at ceiling, on a wall, on the floor, on a table/furniture) of a house, an apartment, a warehouse, a parking lot, a building, a mall, a stadium, a station, an interchange, an office, a room, a meeting room, a warehouse, a facility, a public facility, a bathroom, a toilet, a staircase, a lift, etc. The Type 1 device(s) and/or Type 2 device(s) may be embedded in another device such as TV, remote control, set-top box, audio device, speaker, camera, router, access point, appliance, refrigerator, smoke detector, stove, furniture, chair, sofa, desk, table, vacuum cleaner, smoke detector, lock, tool, WiFi-enabled device, computer, printer, monitor, keyboard, mouse, mouse pad, computer accessory, tablet, phone, clock, alarm clock, thermometer, thermostat, light device, light switch, power socket, power plug, lamp, bedside lamp, bed, computer, phone, tablet, smart plug, charger, extension device, power meter, toy, child item, baby item, baby monitor, adult item, elderly person item, health care item, IoT device, another home device, an office device, a factory device, etc. 
     In one embodiment, there are N1 (e.g. N1=2 or 6 or 100 or 100000) time series of analytics (TSA), each item of each time series being associated with a time stamp. The analytic may be a motion intensity index, a presence/absence, an approaching, a receding, a motion sequence, a motion indicator, a motion direction, a location, a distance, a speed, an acceleration, a timing, a duration, a time period, a periodic motion analytic, a frequency, a period, a transform, a function/transformation of another analytic, a regularity, a transient measure, a manifestation, a revelation, a sign, a vital sign, an impact, a change, a deformation, a hand signal, a gesture signal, a health symptom, a duration, a count, a classification of motion, a breathing parameter/characteristics/statistics, a gait, a hand motion, gesture, a body language, a dancing move, a formation, an event, a state, status, a stage, an indicator of a motion/an event/a condition/a situation/a state, a digital representation (e.g. taking on value of 0 and 1), a continuous/analog representation (e.g. taking on any value between A and B, where A may be 0 or another value, B may be 1 or another value), etc. Some, if not all, analytics may be obtained/determined/computed based on the channel information (CI). 
     Any TSA may be sampled/computed/obtained at regular or irregular time interval. In a TSA, the analytics may be obtained (sampled) regularly for some time, irregularly for some time, intermittently for some time or spontaneously for some time. The analytics may be sampled at a low rate (e.g. 10 Hz) in a time period (e.g. 1 hour), and at a higher rate (e.g. 1000 Hz) in another time period (e.g. 5 minutes). A temporal change in the sampling may be in response to a change (e.g. in environment, detected motion/event/sign). For example, the sampling rate may be low in a standby mode and may be changed to high in an alarming mode or danger mode. For a particular time t, all or some or none of the N1 TSA may have an item associated with the time stamp (i.e. t). 
     There are two ways to present the N1 TSA. In the first way (same-graph presentation), there is one graph with N1 curves (basically N1 graphs superimposed on each other), with the y-axis (or y- and z-axes if an analytics is 2-dimensional, or M-dimensional if an analytics has M dimension) representing the N1 analytics and the x-axis representing time. To maximize the visualization of each analytics, the range of the y-axis may be mapped to different ranges of different analytics (e.g. from 0 to 1 for first analytics, from −10 to 10 for second analytics, from 0 to 100 for the third analytics, from 0 to 10 million for the fourth analytics and so on) while the x-axis is the time axis common to all the N1 curves. If a vertical line is drawn at a particular time t, it intersects with each curve at a point. Thus there are N1 intersection points on the vertical line, one for each curve. 
     In the second way of presenting the N1 TSA (separate-graph presentation), there are N1 separate graphs, one for each analytics. For ease of comparison, suppose the x-axes (time axes) of all graphs are the same/identical, and suppose that all graphs are time synchronized, with essentially same “width” so that they can be conveniently stacked. In each graph, there is only one curve of the analytics (e.g. it may be identical to the respective curve of the analytics drawn in the same-graph presentation with same x-axis and y-axis). The N1 graphs are stacked/placed vertically (e.g. positioned one on top of another), with the y-axis of the graphs co-linear (in a straight line) and the range of the y-axis of each graph mapped to the same respective range as in the same-graph presentation. If a vertical line is drawn at time t in a graph, there is only one intersection in each graph—because there is only one curve. If a vertical line is drawn at time t through the N1 graphs, there will be N1 intersection points—one in each graph. 
     In one embodiment of the present teaching, the N1 TSA may be presented in a novel hybrid way (hybrid presentation), with characteristics of both the same-graph and separate-graph presentation. In one way, the N1 TSA may be combined to be a single combined TSA and the combined TSA may be presented in a single combined graph with a single combined curve. Recall that in the separate-graph presentation, there may be N1 curves in N1 graphs (1 curve for each graph) stacked/placed vertically. All the graphs may have the same time axis or x-axis (synchronized). In the hybrid presentation, all the N1 graphs in the separate-group presentation may be merged into a “combined graph”. The common time axis may be partitioned to form M partitions (e.g. partition 1 from time t_0 to time t_1, partition 2 from t_1 to t_2, . . . , partition M from time t_{M−1} to t_M). The M partitions may or may not span the whole time axis. In other words, there may or may not be gaps between adjacent partitions. The length (or duration) of different partitions may be different. 
     In the hybrid presentation, for each partition, only one of the N1 curves may be selected (to form part of the combined curve) and displayed, while the rest of the N1 curves (the remaining N1−1 curves) may not be displayed. Alternatively, a new combined TSA may be formed with the analytics in each partition chosen from the corresponding TSA associated with the selected curve. The hybrid presentation is equivalent to displaying the new combined TSA. 
     One may define an indicator function I(t) which takes on integer values in the range of 1 to N1. For each partition, the indicator function value is the value of the selected curve. For example, I(t)=k if the k{circumflex over ( )}{th} curve is the selected curve at time t. One may define I_k(t), with k=1, . . . , N1, to be an indicator function of the selection of the k{circumflex over ( )}{th} curve, taking on a value of 1 if the k{circumflex over ( )}{th} curve is selected at time t, and a value of 0 otherwise. Then mathematically, 
         I ( t )=sum_{ k= 1}{circumflex over ( )}{ N 1} k*I _ k ( t )
 
     Let f_k(t) be the function corresponding to the k{circumflex over ( )}{th} curve. Then the displayed function f(t) in the hybrid presentation may effectively be: 
         f ( t )=sum_{ k= 1}{circumflex over ( )}{ N 1} f _ k*I _ k ( t )
 
     Alternatively, the indicator function, I(t), may itself be displayed in the hybrid presentation to indicate which curve (TSA) is active, dominant, or selected, or highlighted, especially when the analytics are indicator of some mutually exclusive states (e.g. REM, NREM and AWAKE sleep states, or SLEEP and NO-SLEEP states, or MOTION and NO-MOTION states), or events (rest room visit). 
     Alternatively, all the N1 curves may be displayed in a first manner (e.g. in a non-dominant manner, in a subtle manner, in a background manner, and/or in less eye-catching manner, with light color, pastel color, grey color, unsaturated color, broken line, dotted line, lower intensity, smaller line thickness, broken/dotted line type, less intensity (e.g. zero intensity, i.e. not displayed), higher transparency (e.g. not visible, half-visible), and/or intermittent line type, etc.). For each partition, the selected curve may be displayed in a second manner (e.g. in a dominant manner, in a non-subtle manner, in a foreground manner, and/or in more eye-catching manner, with dark color, strong color, black, saturated color, solid line, higher intensity, larger line thickness, strong line type, more intensity, lower transparency, and/or continuous line type, etc.) instead of the first manner. This is similar to displaying the N1 TSA as N1 curves in the first manner and the new combined TSA as a curve in the second manner. 
     In the alternative way of hybrid display, the N1 curves may still be displayed similar to how they would be displayed in the separate-graph presentation. They may be stacked and placed vertically, similar to the separate-graph presentation. Each may or may not be displayed with its x-axis (or time axis), where the N1 x-axis may be replaced by a single line (with/without markings to show time scale) to indicate the location of axis. 
     Suppose the separation of adjacent graphs is P. Then, stacking the N1 graphs is similar to forming and displaying the function 
         f ( t )=sum_{ k= 1}{circumflex over ( )}{ N 1}( f _ k+k*P )* I _ k ( t ),
 
     such that adjacent “curves” are separated by a distance of P. If one chooses not to display the f_k and set P=1, the displayed function will be the indicator function I(t): 
         I ( t )=sum_{ k= 1}{circumflex over ( )}{ N 1} k*I _ k ( t ).
 
     More generally, the function displayed may be 
         f ( t )=sum_{ k= 1}{circumflex over ( )}{ N 1}( f _ k+a _ k )* I _ k ( t ),
 
     for some a_k values. In various embodiments, a_k can be k*P but can also be irregular. 
     Between the partitions, the curves may or may not be connected using a line (e.g. a straight line, a curve, etc.). If there is no gap between two adjacent partitions, the curves in the two adjacent partitions may be connected by a vertical line. In this way, there may be only one combined curve in the combined graph, with the line segment in any time partition being the line segment of one of the N1 curves. The combined curve may resemble a continuous function moving among the different graphs (or different curves). If a vertical line is drawn at time t (of a particular partition), it intersects with the combined curve at only one point (on the selected curve associated with the partition). At time t, the selected graph may be considered the “current” graph. The selected curve may be considered the “current” curve. The partition/segment may be considered the “current segment”. The segments and the axis may be labeled. In an example, N1=6 TSA in a well-being monitoring application with two Type 1 devices and one Type 2 device in the home of a user living alone. A Type 1 device and the Type 2 device may be placed next to the user&#39;s bed. The other Type 1 device may be placed in a rest room. There are two wireless links: one between the first Type 1 device and the Type 2 device, and one between the second Type 1 device and the Type 2 device. One (or more, if more than one antenna/device) time series of channel information (TSCI) may be obtained for each wireless link based on a wireless signal being transmitted from the respective Type 1 device to the Type 2 device. For each wireless link, analytics (e.g. motion, breathing, etc.) may be computed based on the respective TSCI. 
     In this example, there may be N1=6 analytics, comprising 6 indicators of: (I1) REM sleep, (I2) NREM sleep, (I3) awake, (I4) restroom, (I5) in-house activity, and (I6) no presence. In general, each indicator may take on values of 1 and 0. An indicator value of 1 may mean the description is active/happening/assertive, while a value of 0 may mean not active/not happening/not assertive. When (I1) is 1, REM (rapid eye movement) sleep may be detected (happening). When (I1) is zero, REM sleep may not be detected (not happening). The first three analytics, (I1) to (I3), may represent different stages of sleep (REM, NREM or non-REM, AWAKE), active when the user is in SLEEP state (as opposed to NO-SLEEP state) typically taking turns to be asserted during bed time of a user. In a way, (I1) to (I3) are three sub-states of the SLEEP state. That is, when the user has a good sleep, the AWAKE stage may be absent. These three analytics may be obtained from some sleep analysis procedure based on the TSCI. In some situations, these three analytics may be combined as one combined sleep analytics taking on four values: REM, NREM, AWAKE and NOT ASLEEP. Typically, a function such as the combined sleep analytics may be decomposed into, or represented as, a weighted sum of simple indicator functions. Analytics (I4) may be asserted when activity (e.g. motion) is detected in the rest room. Analytics (I5) may be asserted when activity is detected in the rest of the house. Analytics (I6) may be asserted when no activity is detected. Typically, only one indicator is active while the others are not active. 
     In a separate-graph presentation, there may be 6 graphs, each with a function (a curve). Let f_1(t) be the function for analytics (I1), f_2(t) for (I2), . . . , and f_6(t) for (I6). In the hybrid display, the combined function may be displayed with the original 6 graphs stacked and labeled. For example the curve of (I1) may be labeled as “REM”; (I2) curve may be labeled as “NREM”, (I3) curve may be labeled as “Awake”, (I4) curve may be labeled as “Activities”, (I5) curve may be labeled as “Bathroom”, and (I6) curve may be labeled as “No activity”. Different sections of the combined function may be labeled. For example, the user may go to bed at 9 pm with the combined function taken on (I4) immediately before 9 pm and (I1) soon after 9 pm. The transition from (I4) to (I1) may be a vertical line labeled as “Go to bed”. Periods of (I5) may be labeled as “Bathroom”. A similar process may go on. 
     Each indicator may be associated with a value, e.g. (I1) associated with a_1, (I2) associated with a_2, (I3) associated with a_3, (I4) associated with a_4, (I5) associated with a_5, and (I6) associated with a_6. The combined function (or combined curve) may take on these values. The combined curve may be represented as (a_1+f_1(t))*I_1(t)+(a_2+f_2(t))*I_2(t)+(a_3+f_3(t))*I_3(t)+(a_4+f_4(t))*I_4(t)+(a_5+f_5(t))*I_5(t)+(a_6+f_6(t))*I_6(t). A possible combination is a_1=P, a_2=2P, a_3=3P, a_4=4P, a_5=5P, a_6=6P for some P so that the N1 graphs are spaced apart (e.g. with corresponding x-axis at a distance of P apart). Another possible combination is a_1=a_2=a_3=a_4=a_5=a_6, in which case the hybrid presentation may degenerate into same-graph presentation. 
     In another embodiment, the analytics may be 2-dimensional and the TSA may be presented as a curve in a 3-dimensional space (with x-axis being time, and y- and z-axes being the analytics) instead of a curve in 2-dimensional space (with x-axis being time and y-axis being the analytics). The N1 curves in 3-D space corresponding to the N1 TSA may be stacked/placed in parallel. The time axis may be divided in the M partitions. In each partition, only one of the N1 curves may be selected/displayed, while the other (N1−1) curves are not displayed. In yet another embodiment, the analytics may be K-dimensional and the TSA may be presented as a curve in K-dimensional space. The N1 curves corresponding to the N1 TSA may be spaced apart. The time axis may be divided in the M partitions. In each partition, only one of the N1 curves may be selected/displayed/animated/highlighted, while the other (N1−1) curves may not be selected/displayed/animated/highlighted. 
     The time-stamped data may be presented in a graphical user interface (GUI). The GUI may have a button which when clicked triggers a new page to show the combined curve, e.g. combined curve of (I1), (I2), (I3), (I4), (I5) and (I6). The time scale (or time period) may be user selectable (e.g. 7-day, 24-hour period, 12-hour period, 8-hour period, 1-hour, 30-minute, 15-minute, 5-minute, 1-minute). The user may click on a section of the combined curve corresponding to a particular time partition with a particular selected curve. The click may cause a new page to appear showing the selected curve. In the above example, when the user clicks on the combined graph where (I2) NREM sleep is selected, the new page may show the selected curve, (I2) NREM sleep. Alternatively, the new page may show the selected curve, (I2) NREM sleep, together with some related curves such as (I1) REM sleep, or (I3) AWAKE, because together (I1), (I2) and (I3) are sub-states of the SLEEP state. In this case, the combined curve of (I1), (I2) and (I3) may be display. Alternatively, (I1), (I2) and (I3) may be displayed using the traditional same-graph presentation, or the traditional separate-graph presentation. While the combined curve (e.g. of (I1), (I2), (I3), (I4), (I5) and/or (I6)) is shown, the user may select a subset of the curves, for example, (I1), (I2) and (I3). This may cause a new page to appear showing a combined curve of (I1), (I2) and (I3). Alternatively, the new page may show (I1), (I2) and (I3) using the same-graph presentation, or the separate-graph presentation. 
     The GUI may show/display analytics such as (a) time for bed, (b) wake up time, (c) total time of sleep, (d) number of awakening during main sleep, (e) sleep score of main sleep, (f) number of times not at home or in room, (g) number of bathroom visits, (h) activity time duration, (i) no-activity time duration, (j) bathroom time duration. The analytics may be computed for a user-selectable time scale (e.g. 8 hours, 12 hours, 24 hours, 3 days, 7 days, 14 days, 1 month, 3 months, 6 months, 1 year). The instantaneous analytics may be displayed. An emoticon (or some graphics showing good versus bad) may be displayed when the analytics is average, above average or below average. A history of the analytics may be displayed for a time period (e.g. past week) at the user-selectable time scale. For example, the number of bath room visits may be displayed for a week, or a month, or a year to show long term trend and any anomaly. 
     In another view of GUI, sleeping states may be displayed for a time window (e.g. 7 days). For each day, the sleeping may be represented by a colored bar. Period of NO-SLEEP, SLEEP, REM, NREM and AWAKE may be represented by different colors. For example, NO-SLEEP may be transparent, AWAKE may have a light color, NREM may have a darker color, and REM may have a darkest color. The time window may be changed by the user (e.g. previous 7 day, previous 7 days, next 7 days, next 7 days, etc.). The GUI may have a button which when clicked causes a new page to appear showing a monthly view, or a weekly view, or a daily view, or an hourly view, or a timed view. 
       FIG. 19  illustrates an exemplary day view showing separate instances of sleep, according to some embodiments of the present teaching. A user can toggle back and forth using the arrows to view the previous or next days&#39; sleep (this also includes naps—there can be more than one sleep in a day). On the top, a hypnogram is displayed. These are the different stages of sleep over the course of a night. On the bottom key sleep statistics are displayed. Sleep Score is calculated using some proposed custom equation that takes into account total sleep time and the time in each stage. It is to give users a holistic view of how they slept. 
       FIG. 19A  and  FIG. 19B  illustrate exemplary weekly views showing a 24 hour scale, according to some embodiments of the present teaching. Sleep of each day(s) is displayed horizontally. The user can view sleep start time, sleep end time, and the different stages throughout the night, represented with different shades of green (see legend). The user can zoom-in on chart to get a better view of these sleep stages. As shown, the X-axis changes to a smaller scale. 
       FIG. 20A  and  FIG. 20B  illustrate exemplary home views showing real-time breathing rate and movement index, according to some embodiments of the present teaching. Breathing rate is in breaths per minute, which will appear as a line that slides horizontally and is constantly changing. Movement index shows a rough picture of a sleeping person&#39;s motion. The point is for it to show large movements (such as tossing and turning) that would cause the breathing rate to drop off. This can enable the user to know that the sleeping person has not actually stopped breathing. There may be just motion that disrupts the breathing signal. Movement index will appear as vertical bars. 
       FIGS. 21-27  illustrate more exemplary views of lifelog display, according to some embodiments of the present teaching. In one embodiment, in each of  FIGS. 18-27 , the elements on each display may be associated with each other. For example, the hypnogram shown in  FIG. 18  is for sleep monitoring data within a day. But once the user clicks on the “week” button at the bottom of the display in  FIG. 18 , the hypnogram will automatically be changed to show sleep monitoring data within a week. In one embodiment, after receiving an input from a user via a GUI displayed in any of  FIGS. 18-27 , the system performs data processing based on the input and generates updated data for display via the GUI. For example, after the user clicks the “Services” button at the bottom of  FIG. 27 , and selects one or more services, the system may associate the user&#39;s sleep data and/or other health or life related data to these services. As such, the system can present the user with these services (e.g. automatic 911 calling, reminder for sleeping, getting up, running, taking medicine, etc.) based on the user&#39;s sleep and/or life data logs. In addition, the system may collect, via the Type 1 and Type 2 devices described above, more life data of the user related to these services to improve user experience of these services. The data collection can be periodically based on a predetermined period, and/or dynamically in response to a user&#39;s input. 
     The following numbered clauses provide additional implementation examples. 
     Clause E1: A method/system/software/device of the presentation system, comprising: determining more than one time series of analytics (TSA) based on a processor, a memory communicatively coupled with the processor and a set of instructions stored in the memory; determining a common time axis for the more than one TSA; presenting the more than one TSA synchronously and jointly in a hybrid manner based on the common time axis. 
     Clause E2: The method/system/software/device of the presentation system of Clause E1: wherein a first TSA is at least one of: dependent, independent, synchronous, and asynchronous, with respect to a second TSA. 
     Clause E3: The method/system/software/device of the presentation system of Clause E1: wherein sampling of a first TSA is at least one of: dependent, independent, synchronous, and asynchronous, with respect to sampling of a second TSA. 
     Clause E4: The method/system/software/device of the presentation system of Clause E1: wherein a sampling attribute of a first TSA is at least one of: the same as, similar to, and different from, the sampling attribute of a second TSA; wherein the attribute comprises at least one of: time, frequency, period, interval, timing, time lag, time stamp, regularity, repetitiveness, variability, impulsiveness, pause, lapse, time-out, duration, source, type, sensor, memory, size, buffering, storage, mechanism, carrier frequency, carrier bandwidth, carrier band, modulation, precision, dynamic range, representation, fixed point, floating point, little endian, big endian, encapsulation, coding, encryption, scrambling, filtering, transformation, preprocessing, processing, postprocessing, noise floor, denoising, uncertainty, environment control, sensing condition, sensing setting, background attribute, dependence, inter-dependence, co-dependence, triggering, priority, instantaneous behavior, short-term behavior, long-term behavior, and another sensing attribute. 
     Clause E5: The method/system/software/device of the presentation system of Clause E1, further comprising: wherein an analytics comprises at least one of: scalar, vector, matrix, n-tuple, collection, set, subset, element, group, collection, mixture, Boolean, label, description, alphanumeric quantity, labeled quantity, time quantity, frequency quantity, statistical quantity, event quantity, sliding quantity, time-stamped quantity, processed quantity, attribute, motion intensity index, motion statistics, TRRS, presence/absence, approaching, receding, motion sequence, motion indicator, motion direction, security information, safety information, intrusion, alarm, alert, location, localization, distance, speed, acceleration, angle, angular speed, angular acceleration, timing, duration, time period, periodic motion analytic, frequency, period, transform, function/transformation of another analytic, distance measure of another two analytics, regularity, dependence, transient measure, manifestation, revelation, sign, vital sign, breathing rate, heart rate, impact, change, deformation, hand signal, gesture signal, health symptom, duration, count, classification of motion, health condition, biometric, sleep parameter, sleep score, sleep duration, sleep timing, sleep interruption, in-sleep, non-sleep, sleep stage, rapid-eye-movement (REM), non-REM (NREM), awake, detection/recognition/verification/tracking/monitoring/tracking/counting/locationing/localization/navigation/guidance/occurrence/co- occurrence/relationship/filtering/processing/preprocessing/postprocessing/correction/activation/accessing/parameter/characteristics/feature/representation/statistics/state/status/stage/condition/situation/indicator/transition/cha nge/timing/classification/information of, or deduction/inference/observation/summarization/decision/conclusion with respect to, at least one of: intruder, people, user, pet, human, child, older adult, patient, intruder, pet, animal, object, material, tool, machine, device, car, defect, fault, motion, movement, motion sequence, event, presence, proximity, activity, daily activity, behavior, movement, phenomenon, history, trend, variation, change, regularity, irregularity, repetitiveness, periodic motion, repeated motion, stationary motion, cyclo-stationary motion, regular motion, breathing, heartbeat, vital sign, gait, motion/feature/cycle/characteristics of body parts/hand/elbow/arm/leg/foot/limbs/head/waist/wrist/eye during walking/running/exercise/locomotion/activity/man-machine interaction, transient motion, impulsive motion, sudden motion, fall-down, danger, life threat, user-interface, gesture, hand sign, handwriting, keystroke, facial expression, facial feature, emotion, body feature, body language, dancing movement, rhythmic movement, periodic motion, channel information (CI), channel state information (CSI), channel impulse response (CIR), channel frequency response (CFR), signal strength, angle-of-arrival (AoA), time-of-arrival (ToA), beamforming information, spectrum, derived analytics based on CI, and another analytics. 
     Clause E6: The method/system/software/device of the presentation system of Clause E1, further comprising: computing at least one hybrid, synchronous, and joint (HSJ) presentation based on the more than one TSA and the common time axis, wherein HSJ presentation comprises at least one of: a same-graph presentation, a separate-graph presentation and a hybrid presentation; presenting the at least one HSJ presentation on a device. 
     Clause E7: The method/system/software/device of the presentation system of Clause E6, further comprising: partitioning the common time axis into a number of time segments, wherein the HSJ presentation is at least one of: a graphical representation, a figure, and a plot, of the TSHA, wherein each time segment of the TSHA in the HSJ presentation is associated with at least one of: a line, line type, line color, line width, line attribute, area, region, shading color, shading type, shading texture, shading attribute, boundary, boundary type, boundary color, boundary width, boundary attribute, surface, surface color, surface type, surface texture, surface shading, surface attribute, animation, flashing, fade-in, fade-out, transition effect, label, symbol, graphical effect, voice, volume, user-interface setting, music, sound effect, and another presentation attribute. 
     Clause E8: The method/system/software/device of the presentation system of Clause E7, further comprising: wherein the number of time segments are consecutive and disjoint. 
     Clause E9: The method/system/software/device of the presentation system of Clause E6, further comprising: computing a time series of hybrid analytics (TSHA) based on at least one of: the more than one TSA, and the common time axis, wherein each hybrid analytics is associated with a time stamp; generating a HSJ presentation based on the TSHA. 
     Clause E10: The method/system/software/device of the presentation system of Clause E9, further comprising: wherein the HSJ presentation is at least one of: a graphical representation, an animation, a figure and a plot, of the TSHA. 
     Clause E11: The method/system/software/device of the presentation system of Clause E10, further comprising: storing at least one of: the more than one TSA, the TSHA, and the HSJ presentation, and the TSHA; communicating at least one of: the more than one TSA, the TSHA, and the HSJ presentation to the device. The TSHA may be indicator function of respective time segments (being constant in the respective time segments and taking on value (analytics ID) unique to the TSA. 
     Clause E12: The method/system/software/device of the presentation system of Clause E9, further comprising: partitioning the common time axis into a number of time segments; for each of the number of time segments: associating the time segment with one of the more than one TSA, and constructing the time segment of the TSHA based on the association. 
     Clause E13: The method/system/software/device of the presentation system of Clause E12: wherein the number of time segments are consecutive and disjoint. 
     Clause E14: The method/system/software/device of the presentation system of Clause E12, further comprising: associating each TSA with a unique analytics ID, each analytics ID being a real number; for each of the number of time segments: assigning at least one hybrid analytics of the TSHA in the time segment to be the analytics ID associated with the time segment. 
     Clause E15: The method/system/software/device of the presentation system of Clause E14: wherein there are N1 TSA; wherein the unique analytics ID is one of N1 consecutive integers. 
     Clause E16: The method/system/software/device of the presentation system of Clause E14: wherein there are N1 TSA; wherein the unique analytics ID is one of N1 equally spaced integers. The TSHA may be individual TSA restricted to respective time segments. 
     Clause E17: The method/system/software/device of the presentation system of Clause E9, further comprising: partitioning the common time axis into a number of time segments; for each of the number of time segments: associating each respective time segment with one of the more than one TSA, and constructing the respective time segment of the TSHA based on the respective time segment of the associated TSA. 
     Clause E18: The method/system/software/device of the presentation system of Clause E17, further comprising: for each of the number of time segments: constructing hybrid analytics in the respective time segment of the TSHA by copying analytics from the respective time segment of the associated TSA. 
     Clause E19: The method/system/software/device of the presentation system of Clause E6, further comprising: computing more than one graphs using the common time axis, each associated with a TSA; synchronizing the more than one graphs by restricting the graphs to a common time window and a common time scale such that they have a similar width; stacking the more than one synchronized graphs such that the time axes of the graphs are parallel and aligned; generating a HSJ by merging (or joining) the more than one stacked synchronized graphs. 
     Clause E20: The method/system/software/device of the presentation system of Clause E19, further comprising: scaling the TSA associated with each graph such that all stacked synchronized graphs have a similar height. 
     Clause E21: The method/system/software/device of the presentation system of Clause E20, further comprising: partitioning the common axis into a number of time segments; associating each time segment with one of the more than one TSA; constructing a highlighted graph by copying, for each respective time segment, respective stacked synchronized graph associated with the respective time segment; generating the HSJ by presenting the highlighted graph in a dominant way and the stacked synchronized graphs in a subservient way. 
     Clause E22: The method/system/software/device of the presentation system of Clause E21, further comprising: wherein each of: the highlighted graph and the stacked synchronized graphs, in a time segment is associated respectively with at least one of: a line, line type, line color, line width, line attribute, area, region, shading color, shading type, shading texture, shading attribute, boundary, boundary type, boundary color, boundary width, boundary attribute, surface, surface color, surface type, surface texture, surface shading, surface attribute, animation, flashing, fade-in, fade-out, transition effect, label, symbol, graphical effect, voice, volume, user-interface setting, music, sound effect, and another presentation attribute. 
     Clause E23: The method/system/software/device of the presentation system of Clause E22, further comprising: wherein a segment of the highlighted graph is at least one of: connected, and not connected, with a neighboring segment of the highlighted graph; wherein the connection, if any, is associated with a presentation attribute. 
     Clause E24: The method/system/software/device of the presentation system of Clause E21, further comprising: stacking the more than one synchronized graphs in a user-defined order. 
     Clause E25: The method/system/software/device of the presentation system of Clause E21, further comprising: stacking a subset of the more than one synchronized graphs such that the time axes of the graphs are parallel and aligned; generating another HSJ by merging (or joining) the subset of more than one stacked synchronized graphs. 
     Clause E26: The method/system/software/device of the presentation system of Clause E21, further comprising: generating another HSJ presentation based on at least one of: another common time window, another time scale, another width, another scaling, another height, a filtering of a TSA, a processing of a TSA, a resampling of a TSA, another TSA, another graph. 
     Clause E27: The method/system/software/device of the presentation system of Clause E6, further comprising: changing the HSJ presentation on the device to another HSJ presentation based on at least one of: a key-press, a user-selection, a device user-interface, a user command, a voice command, a user request, a plan, an animation sequence, a change, a warning, and a server command. 
     Clause E28: The method/system/software/device of the presentation system of Clause E1, comprising: wherein a TSA is computed based on a time series of channel information (TSCI) of a wireless multipath channel; wherein the TSCI is extracted from a wireless signal transmitted from a Type 1 heterogeneous wireless device to a Type 2 heterogeneous wireless device through the wireless multipath channel in a venue. 
     Clause E29: The method/system/software/device of the presentation system of Clause E28, comprising: wherein the wireless multipath channel is impacted by a motion of an object in the venue; wherein the TSA is associated with a monitoring task associated the motion of the object. 
     Clause E30: The method/system/software/device of the presentation system of Clause E29, comprising: monitoring the motion of the object in the venue; wherein the presentation of the more than one TSA synchronously and jointly in the hybrid manner is associated with the monitoring of the motion of the object in the venue. 
     Clause E31: The method/system/software/device of the presentation system of Clause E30, comprising: wherein the monitoring task comprises at least one of: detection/recognition/verification/tracking/monitoring/tracking/counting/locationing/localization/navigation/guidance/occurrence/co- occurrence/relationship/filtering/processing/preprocessing/postprocessing/correction/activation/accessing/parameter/characteristics/feature/representation/statistics/state/status/stage/condition/situation/indicator/transition/cha nge/timing/classification/information of, or deduction/inference/observation/summarization/decision/conclusion with respect to, at least one of: intruder, people, user, pet, human, child, older adult, patient, intruder, pet, animal, object, material, tool, machine, device, car, defect, fault, motion, movement, motion sequence, event, presence, proximity, activity, daily activity, behavior, movement, phenomenon, history, trend, variation, change, regularity, irregularity, repetitiveness, periodic motion, repeated motion, stationary motion, cyclo-stationary motion, regular motion, breathing, heartbeat, vital sign, gait, motion/feature/cycle/characteristics of body parts/hand/elbow/arm/leg/foot/limbs/head/waist/wrist/eye during walking/running/exercise/locomotion/activity/man-machine interaction, transient motion, impulsive motion, sudden motion, fall-down, danger, life threat, user-interface, gesture, hand sign, handwriting, keystroke, facial expression, facial feature, emotion, body feature, body language, dancing movement, rhythmic movement, periodic motion, health, well-being, health condition, sleep, sleep stage, biometric, security, safety, intrusion, event, suspicious event, suspicious motion, alarm, alert, siren, location, distance, speed, acceleration, angle, angular speed, angular acceleration, locationing, and map, energy management, power transfer, wireless power transfer, geometry estimation, map learning, machine learning, machine learning, supervised learning, unsupervised learning, semi-supervised learning, clustering, feature extraction, featuring training, principal component analysis, eigen-decomposition, frequency decomposition, time decomposition, time-frequency decomposition, functional decomposition, other decomposition, training, discriminative training, supervised training, unsupervised training, semi-supervised training, neural network, augmented reality, wireless communication, data communication, signal broadcasting, networking, coordination, administration, encryption, protection, cloud computing, and another monitoring task. 
     The features described above may be implemented advantageously in one or more computer programs that are executable on a programmable system including at least one programmable processor coupled to receive data and instructions from, and to transmit data and instructions to, a data storage system, at least one input device, and at least one output device. A computer program is a set of instructions that may be used, directly or indirectly, in a computer to perform a certain activity or bring about a certain result. A computer program may be written in any form of programming language (e.g., C, Java), including compiled or interpreted languages, and it may be deployed in any form, including as a stand-alone program or as a module, component, subroutine, a browser-based web application, or other unit suitable for use in a computing environment. 
     Suitable processors for the execution of a program of instructions include, e.g., both general and special purpose microprocessors, digital signal processors, and the sole processor or one of multiple processors or cores, of any kind of computer. Generally, a processor will receive instructions and data from a read-only memory or a random access memory or both. The essential elements of a computer are a processor for executing instructions and one or more memories for storing instructions and data. Generally, a computer will also include, or be operatively coupled to communicate with, one or more mass storage devices for storing data files; such devices include magnetic disks, such as internal hard disks and removable disks; magneto-optical disks; and optical disks. Storage devices suitable for tangibly embodying computer program instructions and data include all forms of non-volatile memory, including by way of example semiconductor memory devices, such as EPROM, EEPROM, and flash memory devices; magnetic disks such as internal hard disks and removable disks; magneto-optical disks; and CD-ROM and DVD-ROM disks. The processor and the memory may be supplemented by, or incorporated in, ASICs (application-specific integrated circuits). 
     While the present teaching contains many specific implementation details, these should not be construed as limitations on the scope of the present teaching or of what may be claimed, but rather as descriptions of features specific to particular embodiments of the present teaching. Certain features that are described in this specification in the context of separate embodiments may also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment may also be implemented in multiple embodiments separately or in any suitable sub-combination. 
     Similarly, while operations are depicted in the drawings in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In certain circumstances, multitasking and parallel processing may be advantageous. Moreover, the separation of various system components in the embodiments described above should not be understood as requiring such separation in all embodiments, and it should be understood that the described program components and systems may generally be integrated together in a single software product or packaged into multiple software products. 
     Particular embodiments of the subject matter have been described. Any combination of the features and architectures described above is intended to be within the scope of the following claims. Other embodiments are also within the scope of the following claims. In some cases, the actions recited in the claims may be performed in a different order and still achieve desirable results. In addition, the processes depicted in the accompanying figures do not necessarily require the particular order shown, or sequential order, to achieve desirable results. In certain implementations, multitasking and parallel processing may be advantageous. 
     The features described above may be implemented advantageously in one or more computer programs that are executable on a programmable system including at least one programmable processor coupled to receive data and instructions from, and to transmit data and instructions to, a data storage system, at least one input device, and at least one output device. A computer program is a set of instructions that may be used, directly or indirectly, in a computer to perform a certain activity or bring about a certain result. A computer program may be written in any form of programming language (e.g., C, Java), including compiled or interpreted languages, and it may be deployed in any form, including as a stand-alone program or as a module, component, subroutine, a browser-based web application, or other unit suitable for use in a computing environment. 
     Suitable processors for the execution of a program of instructions include, e.g., both general and special purpose microprocessors, digital signal processors, and the sole processor or one of multiple processors or cores, of any kind of computer. Generally, a processor will receive instructions and data from a read-only memory or a random access memory or both. The essential elements of a computer are a processor for executing instructions and one or more memories for storing instructions and data. Generally, a computer will also include, or be operatively coupled to communicate with, one or more mass storage devices for storing data files; such devices include magnetic disks, such as internal hard disks and removable disks; magneto-optical disks; and optical disks. Storage devices suitable for tangibly embodying computer program instructions and data include all forms of non-volatile memory, including by way of example semiconductor memory devices, such as EPROM, EEPROM, and flash memory devices; magnetic disks such as internal hard disks and removable disks; magneto-optical disks; and CD-ROM and DVD-ROM disks. The processor and the memory may be supplemented by, or incorporated in, ASICs (application-specific integrated circuits). 
     While the present teaching contains many specific implementation details, these should not be construed as limitations on the scope of the present teaching or of what may be claimed, but rather as descriptions of features specific to particular embodiments of the present teaching. Certain features that are described in this specification in the context of separate embodiments may also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment may also be implemented in multiple embodiments separately or in any suitable sub-combination. 
     Similarly, while operations are depicted in the drawings in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In certain circumstances, multitasking and parallel processing may be advantageous. Moreover, the separation of various system components in the embodiments described above should not be understood as requiring such separation in all embodiments, and it should be understood that the described program components and systems may generally be integrated together in a single software product or packaged into multiple software products. 
     Particular embodiments of the subject matter have been described. Any combination of the features and architectures described above is intended to be within the scope of the following claims. Other embodiments are also within the scope of the following claims. In some cases, the actions recited in the claims may be performed in a different order and still achieve desirable results. In addition, the processes depicted in the accompanying figures do not necessarily require the particular order shown, or sequential order, to achieve desirable results. In certain implementations, multitasking and parallel processing may be advantageous.