Patent Publication Number: US-11653435-B2

Title: System level occupancy counting in a lighting system with a single transmitter and multiple receivers

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is related to U.S. patent application Ser. No. 15/870,057, filed on Jan. 12, 2018, entitled “System Level Occupancy Counting in a Lighting System with Multiple Transmitters and a Single Receiver,” published as U.S. Patent Publication No. 2019/0220729 on Jul. 18, 2019; and U.S. patent application Ser. No. 15/870,003, filed on Jan. 12, 2018, entitled “System Level Occupancy Counting in a Lighting System,” issued as U.S. Pat. No. 11,170,296 on Nov. 9, 2021. 
     BACKGROUND 
     In recent years, a number of systems and methods have been proposed for occupancy counting within a particular area. Examples of such systems include video sensor monitoring systems, radio frequency identification (RFID) systems, global positioning systems (GPS), and wireless communication systems among others. Some of these systems, such as RFID and GPS, utilize various radio frequency (RF) based technologies. However, many of these occupancy counting systems have several disadvantages. For example, the video sensor monitoring system requires a considerable number of dedicated sensors that are expensive and the system requires a large amount of memory for storing data. The RFID systems rely on occupants carrying an RFID tag/card that can be sensed by the RFID system to monitor the occupants. The GPS system uses orbiting satellites to communicate with the terrestrial transceiver to determine a location of the occupant in the area. However, such systems are generally less effective indoors or in other environments where satellite signals may be blocked, reducing accuracy of detecting the occupant in the area. 
     Electrically powered artificial lighting has become ubiquitous in modern society. Since the advent of electronic light emitters, such as lighting emitting diodes (LEDs), for general lighting type illumination application, lighting equipment has become increasingly intelligent with incorporation of sensors, programmed controller and network communication capabilities. Automated control, particularly for enterprise installations, may respond to a variety of sensed conditions, such a daylight or ambient light level or occupancy. Commercial grade lighting systems today utilize special purpose sensors and related communications. 
     There also have been proposals to detect or count the number of occupants in an area based on effects on an RF signal received from a transmitter due to the presence of the occupant(s) in the area. These RF wireless communication systems generally count the number of occupants in the area based on change in signal characteristics of a data packet transmitted by a single receiver and a single transmitter over the wireless network. However, an inaccurate count of the occupants in the area can occur when multiple receivers are receiving the RF signals from one or more transmitters. Further, none of the proposals for detecting or counting the number of occupants provide for the transmission and receipt of the RF signals in the lighting system. 
     SUMMARY 
     The examples disclosed herein improve over RF-based sensing technologies by counting number of occupants in space. 
     Some examples disclosed herein include a radio frequency (RF) based system level occupancy counting in a space. In such examples, occupancy count is determined based on measurements of RF perturbations in an area or space. An example algorithm involves establishing a relationship between the RF perturbations occurring in real time with a pre-determined number of occupancy count prior to the real time. The relationship is compared with the RF perturbations in real time to determine the occupancy count in the area at real time. 
     Other examples disclosed herein include heuristically counting number of occupants in a space. In such examples, occupancy count is determined based on measurements of RF perturbations in an area or space. An example machine learning algorithm involves determining optimized heuristic algorithm heuristic algorithm coefficients associated with the RF perturbations to provide occupancy count in the area at a time. The optimized heuristic algorithm heuristic algorithm coefficients are utilized in the example machine learning algorithm to provide the occupancy count in the area at real time. In one example, prior to the real time occupancy count, learning occurs to optimize the heuristic algorithm coefficients, for example, prior to shipping of a product or as part of commissioning. In another example, learning occurs in real time operation, thus resulting in an on-going learning process to further optimize the heuristic algorithm coefficients. 
     An example system includes a plurality of lighting elements. Each of the plurality of lighting elements is a luminaire and includes a light source to illuminate an area. The system also includes a wireless communication transmitter for wireless radio frequency (RF) spectrum transmission in the area, including RF spectrum transmission at a plurality of times. The transmitter is integrated into one of the lighting elements. The system also includes a plurality of wireless communication receivers configured to receive RF spectrum signals of transmissions from the transmitter through the area at the plurality of times. Each of the plurality of the receivers is configured to generate an indicator data of a signal characteristic of received RF spectrum signal at each of the plurality of times. Each of the plurality of receivers is integrated into one of the lighting elements. The system further includes a processing circuitry coupled to obtain the indicator data of RF spectrum signal generated at each of the plurality of times from each of the plurality of receivers. The processing circuitry is configured to at each respective one of the plurality of times, for each respective one of the plurality of receivers; apply one of a plurality of heuristic algorithm coefficients to each indicator data of an RF spectrum signal from the transmitter received by the respective receiver at the respective time; based on results of the application of the heuristic algorithm coefficients, generate an indicator data metric value for each of the indicator data generated by the respective receiver for the respective time; and process each of the indicator data metric value to compute a plurality of metric values associated with the respective receiver for the respective time. Each of the plurality of metric values provide a measurement of each of a plurality of a probable number of occupants in the area for the respective time. The processing circuitry is also configured to combine the plurality of metric values associated with each of the plurality of receivers to compute an output metric value for each of the plurality of probable number of occupants in the area for the respective time. At each respective one of the plurality of times, the processing circuitry is configured to determine an occupancy count in the area at the respective time based on the computed output metric values for each of the plurality of probable number of occupants in the area. 
     An example method includes obtaining, in a lighting system, an indicator data generated at each of a plurality of times from each of a plurality of receivers configured to receive radio frequency (RF) spectrum signals from a RF transmitter in an area. The lighting system includes a plurality of lighting elements. At each respective one of the plurality of times in the lighting system, the method also includes applying a plurality of heuristic algorithm coefficients to each indicator data from each of the plurality of receivers for the respective time, based on results of the application of the heuristic algorithm coefficients to the indicator data, generating an indicator data metric value for the indicator data generated by the respective receiver for the respective time, processing each of the indicator data metric for each of the indicator data to compute a plurality of metric values for the respective receiver for the respective time. Each of the plurality of metric values provide a measurement of each of a plurality of a probable number of occupants in the area for the respective time. The method further includes combining the plurality of metric values for the respective receiver to compute an output value for each of the plurality of probable number of occupants in the area for the respective time; and determining an occupancy count in the area at the respective time based on the computed output metric values for each of the plurality of probable number of occupants in the area. 
     Another example system includes a plurality of lighting elements. Each of the plurality of lighting elements is a luminaire and includes a light source to illuminate an area. The system also includes a wireless communication transmitter for wireless radio frequency (RF) spectrum transmission in an area, including RF transmission at a plurality of times. The transmitter is integrated into one of the lighting elements. The system also includes a plurality of wireless communication receivers integrated into other of the lighting elements and configured to receive RF spectrum signals of transmissions from the transmitter through the area at the plurality of times. Each of the plurality of the receivers is configured to generate an indicator data of a signal characteristic of received RF spectrum signal at each of the plurality of times. The system further includes a processing circuitry coupled to obtain the indicator data of the RF spectrum signal generated at each of the plurality of times from each of the plurality of receivers. The processing circuitry is configured to process the indicator data from the plurality of lighting elements to determine an occupancy count in the area at each of the plurality of times. 
     Additional objects, advantages and novel features of the examples 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 objects and advantages of the present subject matter may be realized and attained by means of the methodologies, instrumentalities and combinations particularly pointed out in the appended claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The drawing figures depict one or more implementations in accordance with the present teachings, by way of example only, not by way of limitation. In the figures, like reference numerals refer to the same or similar elements. 
         FIG.  1 A  illustrates an example of a wireless topology of a lighting system with a single transmitter and multiple receivers. 
         FIG.  1 B  illustrates an example of a wireless topology of a lighting system with a single receiver and multiple transmitters. 
         FIG.  2 A  is a functional block diagram illustrating an example of an occupancy count system based on the wireless topology of  FIG.  1 A . 
         FIG.  2 B  is a functional block diagram illustrating another example of an occupancy count system based on the wireless topology of  FIG.  1 A . 
         FIG.  2 C  is a functional block diagram illustrating a further example of an occupancy count system based on the wireless topology of  FIG.  1 A . 
         FIG.  2 D  is a functional block diagram illustrating another example of an occupancy count system based on the wireless topology of  FIG.  1 B . 
         FIG.  2 E  is a functional block diagram illustrating another example of an occupancy count system based on the wireless topology of  FIG.  1 B . 
         FIG.  2 F  is a functional block diagram illustrating further example of an occupancy count system based on the wireless topology of  FIG.  1 B . 
         FIG.  3    illustrates an example of a wireless topology of a lighting system with multiple transmitters and multiple receivers. 
         FIG.  4 A  is a functional block diagram depicting an example of a heuristic occupancy count system based on the wireless topology of  FIG.  3   . 
         FIG.  4 B  is a functional block diagram illustrating another example of a heuristic occupancy count system based on the wireless topology of  FIG.  3   . 
         FIG.  4 C  is a functional block diagram illustrating further example of a heuristic occupancy count system based on the wireless topology of  FIG.  3   . 
         FIG.  5    illustrates an example of a neural network for heuristically determining occupancy count in a lighting system. 
         FIG.  6 A  is a high-level flow chart illustration of an example of a method for a system level determination of an occupancy count. 
         FIG.  6 B  is a high-level flow chart illustration of an example of a method for heuristically determining an occupancy count. 
         FIG.  7    is a functional block diagram illustrating an example relating to a lighting system of networked devices that provide a variety of lighting capabilities and may implement RF-based occupancy counting. 
         FIG.  8    is a block diagram of an example of a lighting device that operates in and communicates via the lighting system of  FIG.  7   . 
         FIG.  9    is a block diagram of an example of a wall switch type user interface element that operates in and communicates via the lighting system of  FIG.  7   . 
         FIG.  10    is a block diagram of an example of a sensor type element that operates in and communicates via the lighting system of  FIG.  7   . 
         FIG.  11    is a block diagram of an example of a plug load controller type element that operates in and communicates via the lighting system of  FIG.  7   . 
         FIG.  12    provides a functional block diagram illustration of a host or server type general purpose computer hardware platform that may be configured to implement some or all of the functional processing examples described with respect to  FIGS.  1 - 6   . 
         FIG.  13    provides functional block diagram illustrations of a user terminal type general purpose computer hardware platforms that may be configured to implement some or all of the functional processing examples described with respect to  FIGS.  1 - 6   . 
     
    
    
     DETALED 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 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. 
     Although there have been suggestions to control lighting based on RF wireless counting results, prior RF-based counting systems have not themselves been integrated as part of a lighting system of which the lighting operation is controlled as a function of the count. Also, prior RF-based counting systems have not themselves been integrated as part of machine learning (ML) in a lighting system of which the lighting operation are controlled as a function of the count. 
     There is also room for improvement in the RF wireless counting algorithms for lighting system control. For example, a ML algorithm in the lighting system may enable a more rapid and real time response so that an occupant entering a previously empty area perceives that the system instantly turns ON the light(s) in the area. As another example, the ML algorithm may offer improved counting accuracy, e.g. to reduce false positives in determining a number of occupants in the area. 
     Also, there is a need to manage the area based on the occupant count. other control and manage functions in the area such as heating, ventilation and air conditioning (HVAC), heat mapping, smoke control, equipment control, security control, etc. instead of or in addition to lighting control. 
     Further, there is room for improvement for accurate determination of a number of the occupant(s) in a region among multiple different regions of the area. False positives may occur when detecting number of occupant (s) in a specific region or sub-area when multiple transmitters are transmitting the RF signals from multiple different regions of the area. For example, a ML algorithm may offer improved occupancy count accuracy, e.g. to reduce false positives in determining the number of occupant(s) in the actual sub-area of interest in the facility. 
     The examples described below and shown in the drawings integrate RF wireless based occupancy count capabilities in one or more lighting devices or into lighting devices and/or other elements forming a lighting system. Examples of an occupancy count system address some or all of the concerns noted above regarding rapid real time detection of changes in occupancy count and/or improved count performance, such as reduction or even elimination of false positive of occupancy count. These advantages and possibly other advantages may be more readily apparent from the detailed description below and illustration of aspects of the examples in the drawings. 
     Referring to  FIG.  1 A , an example of a wireless topology  101  of a lighting element, which includes a single wireless communication transmitter (Tx) and a number of wireless communication receivers (Rx) in physical space/area  105 . In one implementation, an indoor environment is described, but it should be readily apparent that the systems and methods described herein are operable in external environments as well. Specifically, in this example, the area  105  is a room. In one implementation, although, not shown, the area  105  may also include corridors, additional rooms, hallways etc. 
     As illustrated in the example in  FIG.  1 A , the area  105  includes three intelligent system nodes  132 ,  134 ,  136 . Each such system node has an intelligence capability to transmit a signal or receive a signal and process data. In one example, at least one system node includes a light source and is configured as a lighting device or luminaire. In another example, a system node includes a user interface component and is configured as a lighting controller. In another example a system node includes a switchable power connector and is configured as a plug load controller. In a further example, a system node includes detector as well as related circuitry and is configured as a lighting related sensor. 
     System node  132  includes a transmitter T 1  and system nodes  134  and  136  include receivers R 1  and R 2  respectively. In one implementation, occupancy count in the area  105  is detected according to an occupancy counting procedure as will be described below with respect to  FIGS.  2 A,  2 B and  2 C  below. 
     In the wireless topology  101 , the T 1  in the area  105  transmits a RF spectrum (RF) signal for some number (plurality &gt;1) of times. The transmission may be specifically for the occupancy count, although the present teachings also apply to implementations using the RF wireless transmissions for other purposes, such as system network communications (as discussed later regarding other examples). Each of the receivers R 1 -R 2  receives the transmissions of the RF signal through the area  105  for each of the plurality of times from T 1 . Accordingly, each of the R 1  and R 2  is configured to detect a metric of the received RF, which the system (e.g. at one or more of the nodes or another processor in communication with the receivers) uses to determine occupancy count based on the RF spectrum (RF) signals received from the T 1  in the area  105 . 
     Referring to  FIG.  2 A , there is shown a functional block diagram of an example of an occupancy counting system (system)  200  configured to function on a radio frequency (RF) wireless communication network. As illustrated, the occupancy counting system  200  includes a plurality of lighting elements  202   a - 202   n  disposed within the physical space/area  105  such as a room, corridor, etc. as described above with respect to  FIG.  1   . In one implementation, an indoor environment is described, but it should be readily apparent that the systems and methods described herein are operable in external environments as well. 
     In one implementation, the system  200  includes the three intelligent system nodes  132 ,  134  and  136  as described with respect to  FIG.  1 A  above. As discussed above, each such system node has an intelligence capability to transmit and receive data and process the data. Each system node, for example, may include a receiver (R) and/or a transmitter (T) along with another component used in lighting operations. In one example, a system node includes a light source and is configured as a lighting device. In another example, a system node includes a user interface component and is configured as a lighting controller. In another example the system node includes a switchable power connector and is configured as a plug load controller. In a further example, a system node includes a detector as well as related circuitry and is configured as a lighting related sensor. 
     The system node  132  includes a T 1 , and each of the system nodes  134  and  136  includes a R 1  and R 2  respectively. In the implementation shown in  FIG.  2 A , each of the system nodes  132 ,  134  and  136  is integrated in one of the lighting elements  202   a - 202   n  such that the system node  132  is integrated in the lighting element  202   a , the system node  134  is integrated in the lighting element  202   b  and the system node  136  is integrated in the lighting element  202 . Even though the system nodes  132 ,  134  and  136  are shown to be integrated in the lighting elements  202   a ,  202   b  and  202   n  respectively, it should be apparent that the system nodes  132 ,  134  and  136  are integrated in different lighting devices among the lighting devices  202   a - 202   n . In another alternate implementation, two or more of the system nodes  132 ,  134  and  136  may be integrated in the same lighting element. For example, the system node  132  and the system node  134  may both be incorporated in the lighting element  202   a ; or in another example, the system node  134  and the system node  136  may both be incorporated in the lighting element  202   b.    
     As described above, the Tx is configured to transmit RF signals and each of the Rx is configured to receive signals from the Tx. In one implementation, each of the lighting elements  202   a - 202   n  includes a light source  206 , and is configured as a luminaire, for example, may take the form of a lamp, light fixture, or other luminaire that incorporates the light source, where the light source by itself contains no intelligence or communication capability, such as one or more LEDs or the like, or a lamp (e.g. “regular light bulbs”) of any suitable type. The light source  206  is configured to illuminate some or all of the area  105 . In one example, each of some number of individual light sources  206  is configured to illuminate a portions or a regions of the area  105 . Typically, a system will include one or more other system nodes, such as a wall switch, a plug load controller, or a sensor. 
     In one implementation, the system  200  includes processing circuitry  216  coupled to the receivers R 1  and R 2 . In one implementation, the processing circuitry is coupled to one or more of the lighting elements  202   a - 202   n . In an alternate implementation, the processing circuitry  216  is coupled to the system  200  via a network (not shown). In one implementation, the processing circuitry  216  is implemented in a processor executing software or firmware configured to determine occupancy count in the area  105 , although other circuitry or processor-based implementations may be used. In one implementation, the processing circuitry  216  is implemented in firmware of a processor in the R 1  node and/or in the R 2  node. 
     In one implementation, the system  208  includes a controller  218  coupled to the processing circuitry  216 . In one implementation the controller  218  may be the same or an additional processor configured to control operations of elements in the system  200  in response to determination of occupancy count in the area  105 . For example, in an alternate implementation, the controller  218  is configured to process a signal to control operation of one or more light sources  206   a - 206   n . In one alternate implementation, the controller  218  is configured to turn ON one or more light sources  206   a - 206   n  upon the occupancy count of one or more determined by the processing circuitry  216 . In one implementation, the controller  218  is configured to turn OFF one or more light sources  206   a - 206   n  upon the occupancy count of zero determined by the processing circuitry  216 . In another implementation, upon the occupancy count in the area  105 , the controller  218  may be configured to provide other control and management functions in the area such as heating, ventilation and air conditioning (HVAC), heat mapping, smoke control, equipment control, security control, etc. instead of or in addition to control of the light source(s). Accordingly, the system  200  is configured to function on the RF wireless communications network in accordance with an implementation of a local control of light source(s) in the lighting element(s), as well as other automation control of energy, equipment, operational and management, as discussed above, of the area. 
     In yet another implementation, the controller  218  communicates the occupancy count to the lighting network via a data packet. The data packet is received by one or more luminaires in the lighting network, which are configured to turn ON or OFF the light source(s)  206  based on the occupancy count provided in the data packet. The luminaire or another node on the lighting network may receive the packet and respond to provide automation of other energy control, equipment control, operational control and management systems (e.g. HVAC, heat mapping, smoke control, equipment control and security control) in the area. Accordingly, the system  200  communicates the occupancy count with other networks. In another alternate implementation, the controller  218  is coupled to the system  200  via a network (not shown). Accordingly, the system  200  is configured to function on the RF wireless communication network in accordance with an implementation of a global control of light source(s), as well as other automation control of energy, equipment, operational and management, as discussed above, of the area in lighting element(s). 
     In one implementation, the system nodes typically include a processor, memory and programming (executable instructions in the form of software and/or firmware). Although the processor may be a separate circuity (e.g. a microprocessor), in many cases, it is feasible to utilize the central processing unit (CPU) and associated memory of a micro-control unit (MCU) integrated together with a transceiver in the form of a system on a chip (SOC). Such an SOC can implement the wireless communication functions as well as the intelligence (e.g. including any processing or controller capabilities) of the system node. 
     In examples discussed in more detail later, system nodes often may include both a transmitter and a receiver (sometimes referenced together as a transceiver), for various purposes. At times, such a transceiver-equipped node may use its transmitter as part of an occupancy counting operation; and at other times such a transceiver-equipped node may use its receiver as part of an occupancy counting operation. Such transceiver equipped nodes also typically include a processor, memory and programming (executable instructions in the form of software and/or firmware). Although the processor may be a separate circuity (e.g. a microprocessor), in many cases, it is feasible to utilize the central processing unit (CPU) and associated memory of a micro-control unit (MCU) integrated together with physical circuitry of a transceiver in the form of a system on a chip (SOC). Such an SOC can implement the wireless communication functions as well as the intelligence (e.g. including any processing or controller capabilities) of the system node. 
     Although the system nodes  132 ,  134  and  136  of  FIG.  2 A  illustrate an implementation of a single Tx and a single Rx in each of the nodes, the system  200  may include other implementations such as multiple Txs in one or more nodes. Also,  FIG.  2 A  illustrates the implementation of a single Rx in each of the nodes, the system  200  may include other implementations such as multiple Rxs in one or more nodes. In the illustrated implementation, the system  200  includes multiple lighting elements  206   a - 206   n  with either the Tx or the Rx, however, the multiple lighting elements  206   a - 206   n  of the system  200  may include one or more Txs and one or more Rxs (see  FIG.  7   ). 
     For discussion of an initial example of a RF-based occupancy counting operation, assume that the system  200  includes just the elements shown in  FIG.  2 A . In one example, each of the system nodes  132 ,  134  and  136  includes the capabilities to communicate over two different RF bands, although the concepts discussed herein are applicable to devices that communicate with luminaires and other system elements via a single RF band. Hence, in the dual band example, the Tx/Rx may be configured for sending and receiving various types of data signals over one band, e.g. for the RF transmission and reception leading to occupancy counting. The other band may be used or for pairing and commissioning messages over another band and/or for communications related to detection of RF or higher level occupancy counting functions, e.g. between receivers R 1  and R 2  and the controller  220  or the processing circuitry  216 . For example, the Tx and Rx are configured as a 900 MHz transmitter and receiver for communication of a variety of system or user data, including lighting control data, for example, commands to turn lights ON/OFF, dim up/down, set scene (e.g., a predetermined light setting), and sensor trip events. Alternatively, the Tx and Rx may be configured as a 2.4 GHz transmitter and receiver for Bluetooth low energy (BLE) communication of various messages related to commissioning and maintenance of a wireless lighting system and/or to communicate results of processing functions in relation to occupant counting. 
     In one implementation, benefits of the system include the ability to take advantage of Tx and the Rx (e.g. Tx and RF Rx) already installed in a location in the area  105 , and because the system passively monitors signal broadcasts in the area  105  at a plurality of times, the occupancy counting functionality does not require (does not on) the occupants to carry any device. 
     At a high level, the T 1  transmits a RF spectrum (RF) signal at a plurality of times. The transmission may be specifically for the occupancy counting. In some cases, however, where the transmitter is in another lighting device or other lighting system element (e.g. a sensor or a wall switch), the transmissions maybe regular lighting related communications, such as reporting status, sending commands, reporting sensed events, etc. Each of the R 1 -R 2  receives the transmissions of the RF signal from the T 1  through the area  105  during each of the plurality of times. Each of the R 1 -R 2  generates an indicator data of one or more characteristics of the received RF signal at each of the plurality of times. Some of examples of the characteristics include but are not limited to received signal strength indicator (RSSI) data, bit error rate, packet error rate, phase change etc. or a combination of two or more thereof. The RSSI data represents measurements of signal strength of the received RF. The bit error rate is rate of incorrect bits in received RF signals versus total number of bits in the transmitted RF signals. The packet error rate is rate of incorrect packets in received RF signals versus total number of packets the transmitted RF signals. Phase change is a change of phase of a received RF signal compared to previous reception of the RF signal (typically measured between the antennas spaced apart from each other). For the purposes of the present description, we use RSSI data as the characteristics of the RF signals for processing by the R 1 -R 2  receivers to generate as the indicator data. Each of the R 1 -R 2  measures the signal strength of the RF signal received from transmitter T 1  and generates the RSSI data based on the signal strength. The signal strength of each of the RF signal varies over time based whether an occupant exists or there are a number of occupants (plural) in each path between the T 1  and R 1  or R 2  in the area  105 . 
     For each time, each of the receivers R 1 -R 2  supplies the generated indicator data of one or more characteristics of the received RF signal to the processing circuitry  216 . In one implementation using RSSI as the characteristic of interest, the processing circuitry  216  obtains the generated RSSI data at each of the plurality of times from the various receivers R 1 -R 2  and processes the RSSI data to determine occupancy count in the area  105 . 
     In one implementation, the processing circuitry  216  processes the generated RSSI data utilizing a RF signal computation to determine occupancy count in the area  105  in real time. In one implementation, the RF signal is a line-of-sight (LOS) signal and blocking occurs when at least one occupant crosses the path between one of the R 1   134  and/or the R 2   136  and the T 1   132  in the area  105  or is located directly (or close enough) between the one of the R 1   134  and/or the R 2   136  and the T 1   132  (i.e., along the so-called line-of-sight path between the receiver and the transmitter). Similarly, LOS blockage also describes multiple simultaneous occupant crossings or multiple occupants located on the LOS path. LOS blocking causes a measurable decrease in the amplitude or strength of the RF signal received by the R 1   134  and/or R 2   136  for the duration of time the occupant remains in a blocking position. 
     In another implementation using RSSI, the received RF signal includes a multi-path signal which is generated based on a multi-path (MP) scattering/fading. In such an implementation, occupant(s) impact the receive signal as a result of changes they cause in the multi-path (MP) scattering/fading. The MP scattering does not require occupants to be located along a LOS path. Although MP scattering may not decrease the amplitude/signal strength as dramatically as LOS blocking, MP scattering results in a decrease in amplitude/signal strength that is related to the number of occupants located in the area  105 . 
     In a further implementation, the RF signal reception and associated RSSI measurements and processing thereof are based on both the LOS blockage and the MP scattering. 
     In one implementation, the RF signal computation generates theoretical or mathematical models that provide for a pre-determined number of occupants in the area  105  at a time prior to the real time. The theoretical model describes RSSI data or a function of the RSSI data of the RF signals received from the transmitter by the various receivers as they relate to various numbers of possible occupants. Theoretical models may take into account one or more ways in which occupants impact the received signal. For example, modeling may include mathematical modeling of the LOS blocking as a function of potential number of occupants, mathematical modeling of the multi-path (MP) scattering/fading as a function of potential number of people, or a combination of both LOS/MP analysis. In one example, mathematical modeling or LOS, MP or LOS/MP may involve deriving an expression for the probability density function (PDF), probability mass function (PMF), or other statistical or probabilistic function as they relate to various numbers of occupants. In other examples, mathematical analysis can involve other spatio-temporal analysis (mathematical analysis of multiple links over space and time) or other probabilistic spatio-temporal analysis (probabilistic analysis of multiple links over space and time) of the RSSI data. In some examples, the analysis makes use of modeling occupant behavior within the area. In one example, for instance, the speed or average speed of occupants may be assumed and used in the mathematical modeling. In another example, any knowledge of spatial preferences or popular areas can be used in the mathematical modeling. Theoretical models generated are stored, for example in a memory unit (not shown) and subsequently compared to the generated RSSI data for occupancy count in the real time. 
     In one implementation, the processing circuitry  216  compares the generated RSSI data from the plurality of receivers in real time with thresholds or the like produced by the mathematical model. More particularly, in one implementation, the processing circuitry  216  analyzes the generated RSSI data to derive a probability density function (PDF) or probability mass function (PMF) representation of the generated RSSI data that can be compared with the statistical or probabilistic functions derived for the theoretical models as described above. In one implementation, the processing circuitry  216  determines a best match between the PDF/PMF representation of the generated RSSI data in real time and the theoretical or modeled attributes (or functions of the modeled attributes). A variety of methods may be utilized to find the best match or fit between the function describing the RSSI data generated in real time and the function describing the theoretical (modeled) attributes, such as Kullback-Leibler (KL) divergence. 
     In another implementation, the processing circuitry  216  processes the generated RSSI data utilizing a heuristic algorithm to determine an occupancy count in the area  105 . The processing circuitry applies the heuristic algorithm to the indicator data of the RF signals from each of the plurality of receivers to compute an output metric value for each of a plurality of probable number of occupants in the area. The processing circuitry  216  also compares each one of the plurality of computed output metric values with another one of the plurality of computed output metric values to identify one of the plurality of computed output metric values as having a largest value and indicates that the probable number of occupants associated with the computed metric value having the largest value is the current estimate of the occupancy count in the area  105 . Details of the utilizing of the heuristic algorithm are provided herein below. 
     In one implementation that takes advantage of the machine learning (ML) capability of the heurist algorithm, the system  200  includes a trusted detector  230 , which provides a known occupancy count value (similar to the “known answer” as discussed above). Input from the trusted detector  230  enables the processor or the like running the heuristic algorithm to “learn” which outcomes are accurate versus outcomes that are not accurate, so as to improve performance. The trusted detector  230  in the example may be a standard occupancy sensor, such as passive infrared occupancy detector, a high resolution camera, low resolution (pixel) camera, a camera based occupancy counting system, ultra-wide band (UWB) radar other radar systems, or sonar systems. Specifically, the trusted detector  230  provides a known occupancy count value for an accurate occupancy count in the area  105  at each of the multiple times. In one implementation, the known occupancy count value is pre-determined prior to heuristically determining the occupancy count in the area  105 . 
     In one implementation, the processing circuitry  216  obtains the indicator data of the RF signal generated for multiple times (ta-tn) from each of the R 1  and R 2 . The processing circuitry  216  applies one of a heuristic algorithm heuristic algorithm coefficient heuristic algorithm coefficient among a set of heuristic algorithm heuristic algorithm coefficients to each of the indicator data from each of the R 1  and R 2  to generate an indicator data metric value for each of the indicator data from each of the R 1  and R 2  for the times ta-tn. Each heuristic algorithm heuristic algorithm coefficient among the set of heuristic algorithm heuristic algorithm coefficients may be randomly selected at an initial stage of training. In one implementation, a heuristic algorithm heuristic algorithm coefficient is a variable. In one implementation, a value of the heuristic algorithm heuristic algorithm coefficient applied to an indicator data from R 1  is the same as the value of the heuristic algorithm heuristic algorithm coefficient applied to another indicator data that is from R 2 . In another implementation, a value of a first heuristic algorithm heuristic algorithm coefficient applied to an indicator data from the R 1  is different from value of another (second) heuristic algorithm heuristic algorithm coefficient applied to another indicator data from R 2 . In one implementation, the processing circuitry  216  processes the indicator data metric values to compute metric values associated with each of the R 1  and R 2  at each of the times ta-tn. The metric values provide a measurement of each of a plurality of a probable or possible number of occupants in the area for each of the times ta-tn. Some examples of the measurements may include but not limited to percentage, decimal, ratio, rates etc. In one implementation, the processing circuitry  216  combines/adds the metric values associated with R 1  with metric values associated with R 2  to compute an output metric value for each of the plurality of probable number of occupants in the area for each of the times ta-tn. In one implementation, the processing circuity  216  compares each of the plurality of output metric values with one another to determine which of the plurality of output metric values has the highest value. The processing circuitry  216  determines that the probable number of occupants in the area with the largest output metric value as the occupancy count in the area for each of the times ta-tn. In one implementation, the processing circuitry  216  compares the occupancy count in the area with the known occupancy count value generated by the trusted detector for each of the ta-tn. Specifically, the processing circuitry  216  compares the occupancy count in the area at each of the ta-tn with the known occupancy count value, for example, an output of the trusted detector  230 , to determine an accurate occupancy count in the area as described in greater detail below. In one implementation, the system  202  includes a learning module  220  coupled to the processing circuitry  216  to determine whether the set of heuristic algorithm coefficients are optimized heuristic algorithm coefficients based on the comparison by the processing circuitry  216  at the times ta-tn to detect an accurate occupancy count in the area. In one implementation, upon determination, that the set of heuristic algorithm coefficients are optimized heuristic algorithm coefficients, the learning module  220  instructs the processing circuitry  216  to utilize the optimized heuristic algorithm coefficients in real time. In one implementation, upon determination, that the set of heuristic algorithm coefficients are not optimized heuristic algorithm coefficients, the learning module  220  instructs the processing circuitry  216  to update one or more heuristic algorithm coefficients among the set of heuristic algorithm coefficients and utilize the updated one or more heuristic algorithm coefficients in a next time. The above implementations are described in greater detail below. 
     In one implementation, the processing circuitry  216  determines that the occupancy count at a time t 1  among the times ta-tn is same as the known occupancy count value. In one implementation, the learning module  220  determines, that the set of heuristic algorithm coefficients are determined to be optimized heuristic algorithm coefficients to be applied to the indicator data for the time t 1  to determine the accurate occupancy count. In one implementation, the learning module  220  instructs the processing circuitry  216  to utilize the optimized heuristic algorithm coefficients to apply to each indicator data among the plurality of indicator data from each of the plurality of receivers for the time t 1  to detect the occupancy count in real time. Accordingly, the processing circuitry  216  applies the optimized heuristic algorithm coefficients to determine the occupancy count in real time. 
     In another implementation, the processing circuitry  216  determines that the occupancy count at a time t 1  among the times ta-tn is different than the known occupancy count value. The learning module  220  determines that the set of heuristic algorithm coefficients are not optimized heuristic algorithm coefficients and thus updates the one or more heuristic algorithm coefficients among the set of the heuristic algorithm coefficients to generate updated set of heuristic algorithm coefficients. The learning module  220  instructs the processing circuitry  216  to utilize the updated set of heuristic algorithm coefficients in a next time. The processing circuitry  216  applies the updated heuristic algorithm coefficients to corresponding indicator data from each of the R 1  and R 2  to generate an updated indicator data metric value for each of the indicator data from each of the R 1  and R 2  at the time t 1 . In one implementation, the processing circuitry  216  processes each of the updated indicator data metric values to compute updated occupancy count at t 1 . In one implementation, the processing circuitry  216  determines that the updated occupancy count at the time t 1  is the same as the known occupancy count value. As such, the learning module  220  determines that the updated set of heuristic algorithm coefficients are optimized heuristic algorithm coefficients to be applied to the indicator data for the time t 1  to determine the accurate occupancy count in real time. In another implementation, the processing circuitry  216  determines that the updated occupancy count is different than the known occupancy count value. The processing circuitry  216  and the learning module  220  repeats the above process for t 1  until the occupancy count is same as the known occupancy count value to determine that the set of heuristic algorithm coefficients corresponding to the indicator data from each of the R 1  and R 2  are the optimized heuristic algorithm coefficients for the t 1  among the ta-tn to accurately determine the occupancy count at real time. Accordingly, the processing circuitry  216  applies the optimized heuristic algorithm coefficients to determine the occupancy count in real time. 
     In one implementation, the occupancy count is determined for each of the indicator data at each of the ta-tn and compared with the known occupancy count value to determine the optimized heuristic algorithm coefficients for each of the ta-tn to detect an accurate occupancy count in the area  105  of  FIG.  1 A  at each of the ta-tn. In one implementation, the optimized set of heuristic algorithm coefficients for each of the ta-tn are utilized by the processing circuitry  216  to detect accurate occupancy count in the area  105  of  FIG.  1 A  at real time. 
     Referring to  FIG.  2 B , there is shown a functional block diagram of an example of an occupancy counting system (system)  201  configured to function on a radio frequency (RF) wireless communication network. In one implementation, the system  201  is similar to the system  200  of  FIG.  2 A  except the processing circuitry  216  is coupled to the one or more of the lighting elements via a network  240 . In one implementation, the network  240  is a wireless communication network. In one example, the network  240  is a BLE mesh. In one implementation, the network  240  is a wired network. In one implementation, the processing circuitry  216  is a cloud computing system which includes a plurality of processing servers/machines, which work together or independently to process the indicator data to determine the occupancy count in the area  105 . In an alternate implementation, the controller  218  is coupled to the processing circuitry  216  via the network  240 . In such alternate implementation, the controller  218  is a cloud computing system which includes a plurality of processing servers/machines, which work together or independently to control operations of one or more elements (e.g. light source  206   a - 206   n ) of the lighting elements  202   a - 202   n  and/or provide automation of other energy control, equipment control, operational control and management systems (e.g. HVAC, heat mapping, smoke control, equipment control and security control) in the area based on determination of the occupancy count by the processing circuitry  216 . Accordingly, implementation of the system  201  is configured to globally control the light source(s) of the lighting element(s), as well as other automation control of energy, equipment, operational and management, as discussed above, of the area in the lighting system. 
     Referring to  FIG.  2 C , there is shown a functional block diagram of an example of an occupancy counting system (system)  202  configured to function on a radio frequency (RF) wireless communication network. In one implementation, the system  202  is similar to the system  200  of  FIG.  2 A  except the processing circuitry  216  is integrated in a lighting element  202 . The processing circuitry  216  functions to process the indicator data to determine the occupancy count in the area  105  as discussed in detail above. The system  202  also includes plurality of lighting elements  202   a - 202   n  including the lighting element  202 . Although, not illustrated, in an alternate implementation, the processing circuitry  216  is integrated in one of the plurality of lighting elements  202   a - 202   n . Each of the plurality of lighting elements includes a corresponding light source among a plurality of light sources  202   a - 202   n.    
     Referring to  FIG.  1 B , an example of a wireless topology  103  of a lighting system includes a single wireless communication receiver (Rx) and a number of wireless communication transmitters (TXs) in physical space/area  105 . In one implementation, an indoor environment is described, but it should be readily apparent that the systems and methods described herein are operable in external environments as well. Specifically, in this example, the area  105  is a room. In one implementation, although, not shown, the area  105  may also include corridors, additional rooms, hallways etc. As illustrated in the example in  FIG.  1 B , the area  105  includes three intelligent system nodes, out of which two are Tx  132 , and Tx  133 , and one is the Rx  136 . As discussed above, each such system node has an intelligence capability to transmit a signal or receive a signal and process data. In one example, at least one system node includes a light source and is configured as a lighting device or luminaire. In another example, a system node includes a user interface component and is configured as a lighting controller. In another example a system node includes a switchable power connector and is configured as a plug load controller. In a further example, a system node includes detector as well as related circuitry and is configured as a lighting related sensor. In one implementation, occupancy count in the area  105  is detected according to an occupancy counting procedure as will be described below with respect to  FIGS.  2 D,  2 E and  2 F  below. 
     In the wireless topology  103 , the T 1  and T 2  in the area  105  transmits a RF spectrum (RF) signal for some number (plurality &gt;1) of times. The transmission may be specifically for the occupancy count, although the present teachings also apply to implementations using the RF wireless transmissions for other purposes, such as system network communications (as discussed later regarding other examples). The R 1  receives the transmissions of the RF signals through the area  105  for each of the plurality of times from T 1  and T 2 . Accordingly, the R 1  is configured to detect a metric of the received RF, which the system (e.g. at one or more of the nodes or another processor in communication with the receivers) uses to determine occupancy count based on the RF signals received from the T 1  and the T 2  in the area  105 . 
     Referring to  FIG.  2 D , there is shown a functional block diagram of an example of an occupancy counting system (system)  250  configured to function on a radio frequency (RF) wireless communication network. As illustrated, the occupancy counting system  250  includes a plurality of lighting elements  202   a - 202   n  disposed within the physical space/area  105  such as a room, corridor, etc. as described above with respect to  FIG.  1 B . In one implementation, an indoor environment is described, but it should be readily apparent that the systems and methods described herein are operable in external environments as well. 
     In one implementation, the system  250  includes the three intelligent system nodes, as described with respect to  FIG.  1 B  above. As discussed above, each such system node has an intelligence capability to transmit and receive data and process the data. Each system node, for example, may include a receiver (R) and/or a transmitter (T) along with another component used in lighting operations. In one example, a system node includes a light source and is configured as a lighting device. In another example, a system node includes a user interface component and is configured as a lighting controller. In another example the system node includes a switchable power connector and is configured as a plug load controller. In a further example, a system node includes a detector as well as related circuitry and is configured as a lighting related sensor. The system node  134  includes a R 1 , and each of the system nodes  132  and  133  includes a T 1  or T 2  respectively. In the implementation shown in  FIG.  2 D , each of the system nodes  132 ,  134  and  136  is integrated in one of the lighting elements  202   a - 202   n . Even though, the system nodes  132 ,  134  and  136  are shown to be integrated in the lighting elements  202   a ,  202   b  and  202   n  respectively, it should be apparent that the system nodes  132 ,  134  and  136  are integrated in different lighting elements among the lighting elements  202   a - 202   n . In another alternate implementation, two or more of the system nodes  132 ,  134  and  136  may be integrated in the same lighting element. For example, the system node  132  and the system node  134  may both be incorporated in the lighting element  202   a  or in another example, the system node  134  and the system node  136  may both be incorporated in the lighting element  202   b.    
     As described above, each of the Tx is configured to transmit RF spectrum (RF) signals and the Rx is configured to receive signals from each of the Tx. Similar to the system  200  in  FIG.  2 A , each of the lighting elements  202   a - 202   n  in the system  250  of  FIG.  2 D  also includes a light source  206 , and is configured as a luminaire, for example, may take the form of a lamp, light fixture, or other luminaire that incorporates the light source, where the light source by itself contains no intelligence or communication capability, such as one or more LEDs or the like, or a lamp (e.g. “regular light bulbs”) of any suitable type. The light source  206  is configured to illuminate some or all of the area  105 . In one example, each of some number of individual light sources  206  is configured to illuminate a portions or a regions of the area  105 . Typically, a system will include one or more other system nodes, such as a wall switch, a plug load controller, or a sensor. 
     The system  250  also includes processing circuitry  216 . The processing circuitry  216  is coupled to the receivers R 1 . In one implementation, the processing circuitry is coupled to one or more of the lighting elements  202   a - 202   n . In an alternate implementation, the processing circuitry  216  is coupled to the system  200  via a network (not shown). In one implementation, the processing circuitry  216  is implemented in a processor executing software or firmware configured to determine occupancy count in the area  105 , although other circuitry or processor-based implementations may be used. Similar to the system  200  in  FIG.  2 A , the system  250  in FIG.  2 D also includes a controller  218  coupled to the processing circuitry  216 . In one implementation the controller  218  may be the same or an additional processor configured to control operations of elements in the system  250  in response to determination of occupancy count in the area  105 . For example, in an alternate implementation, the controller  218  is configured to process a signal to control operation of one or more light sources  206   a - 206   n . In one alternate implementation, the controller  218  is configured to turn ON one or more light sources  206   a - 206   n  upon the occupancy count of one or more determined by the processing circuitry  216 . In one implementation, the controller  218  is configured to turn OFF one or more light sources  206   a - 206   n  upon the occupancy count of zero determined by the processing circuitry  216 . In another implementation, the controller  218  is configured to provide automation of other energy control, equipment control, operational control and management systems (e.g. HVAC, heat mapping, smoke control, equipment control and security control) in the area upon the occupancy count determined by the processing circuitry  216 . Accordingly, the system  250  is configured to function on the RF wireless communications network in accordance with an implementation of a local control of light source(s) in the lighting element(s), as well as other automation control of energy, equipment, operational and management, as discussed above, of the area in the lighting system. 
     In examples discussed in more detail later, system nodes often may include both a transmitter and a receiver (sometimes referenced together as a transceiver), for various purposes. At times, such a transceiver-equipped node may use its transmitter as part of an occupancy counting operation; and at other times such a transceiver-equipped node may use its receiver as part of an occupancy counting operation. 
     Although,  FIG.  2 D  illustrates the implementation of a single Rx and a single Tx in each of the nodes, the system  203  may include other implementations such as multiple Rx in one or more nodes and multiple Tx in one or more nodes. Further, the system  203  may include one or more Tx and one or more Rx in each of the nodes. In the illustrated implementation, the system  250  includes multiple lighting elements  206   a - 206   n  with either the Tx or the Rx, however, the multiple lighting elements  206   a - 206   n  of the system  200  may include one or more Tx and one or more Rx (see  FIG.  7   ). 
     For discussion of an initial example of a RF-based occupancy counting operation, assume that the system  250  includes just the elements shown in  FIG.  2 D . In one example, each of the system nodes  132 ,  134  and  136  includes the capabilities to communicate over two different RF bands, although the concepts discussed herein are applicable to devices that communicate with luminaires and other system elements via a single RF band. Hence, in the dual band example, the Tx/Rx may be configured for sending and receiving various types of data signals over one band, e.g. for the RF transmission and reception leading to occupancy counting. The other band may be used or for pairing and commissioning messages over another band and/or for communications related to detection of RF or higher level occupancy counting functions, e.g. between receivers R 1  and R 2  and the controller  218  or the processing circuitry  216 . For example, the Tx and Rx are configured as a 900 MHz transmitter and receiver for communication of a variety of system or user data, including lighting control data, for example, commands to turn lights ON/OFF, dim up/down, set scene (e.g., a predetermined light setting), and sensor trip events. Alternatively, the Tx and Rx may be configured as a 2.4 GHz transmitter and receiver for Bluetooth low energy (BLE) communication of various messages related to commissioning and maintenance of a wireless lighting system and/or to communicate results of processing functions in relation to occupant counting. 
     In one implementation, benefits of the system include the ability to take advantage of Tx and the Rx (e.g. RF Tx and RF Rx) already installed in a location in the area  105 , and because the system passively monitors signal broadcasts in the area  105  at a plurality of times, the occupancy counting functionality does not require (does not rely on) the occupants to carry any device. 
     At a high level, each of the T 1  and T 2  transmits a RF spectrum (RF) signal at each of a plurality of times. The transmission may be specifically for the occupancy counting. In some cases, however, where the transmitter is in another lighting device or other lighting system element (e.g. a sensor or a wall switch), the transmissions maybe regular lighting related communications, such as reporting status, sending commands, reporting sensed events, etc. The R 1  receives the transmissions of the RF signals from the T 1  and the T 2  through the area  105  during each of the plurality of times. The R 1  generates an indicator data of one or more characteristics of the received RF signals at the plurality of times. Some of examples of the characteristics include but are not limited to received signal strength indicator (RSSI) data, bit error rate, packet error rate, phase change etc. or a combination of two or more thereof. The RSSI data represents measurements of signal strength of the received RF. The bit error rate is rate of incorrect bits in received RF signals versus total number of bits in the transmitted RF signals. The packet error rate is rate of incorrect packets in received RF signals versus total number of packets the transmitted RF signals. Phase change is a change of phase of a received RF signal compared to previous reception of the RF signal (typically measured between the antennas spaced apart from each other). For the purposes of the present description, we use RSSI data as the characteristics of the RF signal for processing by the R 1  to generate as the indicator data. The R 1  measures the signal strength of the received RF signals transmitted by T 1  and T 2 ; and generate the RSSI data based on the signal strength of the RF signals transmitted by T 1  and T 2 . The signal strength of each of the RF signal varies over time based whether an occupant exists or there are a number of occupants in each a path the T 1  and R 1  and/or the T 2  and R 1  in the area  105 . 
     For each time, the R 1  supplies the generated indicator data of one or more characteristics of the received RF signal to the processing circuitry  216 . In one implementation using RSSI as the characteristic of interest, the processing circuitry  216  obtains the generated RSSI data at each of the plurality of times from the R 1  and processes the RSSI data to determine occupancy count in the area  105 . 
     In one implementation, the processing circuitry  216  processes the generated RSSI data utilizing a RF signal computation to determine occupancy count in the area  105  in real time. In one implementation, the RF signal is a line-of-sight (LOS) signal blocking occurs when at least one occupant crosses the path between one of the T 1   132  and/or the T 2   133  and R 1   134  in the area  105  or is located directly (or close enough) between the one of the T 1   132  and/or the T 2   133  and the R 1   134  (i.e., along the so-called line-of-sight path between the receiver and the transmitter). Similarly, LOS blockage also describes multiple simultaneous occupant crossings or multiple occupants located on the LOS path. LOS blocking causes a measurable decrease in the amplitude or strength of the RF signal received by the R 1   134  for the duration of time the occupant remains in a blocking position. In another implementation, using RSSI, the received RF signal includes a multi-path signal which is generated based on a multi-path (MP) scattering/fading. In such implementation, occupant(s) impact the receive signal as a result of changes they cause in the multi-path (MP) scattering/fading. The MP scattering does not require occupants to be located along a LOS path. Although MP scattering may not decrease the amplitude/signal strength as dramatically as LOS blocking, MP scattering results in a decrease in amplitude/signal strength that is related to the number of occupants located in the area  105 . In a further implementation, the RF signal reception and associated RSSI measurements and processing thereof are based on both the LOS blockage and the MP scattering. 
     As discussed above, in one implementation, the RF signal computation generates theoretical or mathematical models that provide for a pre-determined number of occupants in the area  105  at a time prior to the real time. The theoretical model describes RSSI data or a function of the RSSI data of the RF signals received from the transmitter by the various receivers as they relate to various numbers of possible occupants. Theoretical models may take into account one or more ways in which occupants impact the received signal. For example, modeling may include mathematical modeling of the LOS blocking as a function of potential number of occupants, mathematical modeling of the multi-path (MP) scattering/fading as a function of potential number of people, or a combination of both LOS/MP analysis. In one example, mathematical modeling or LOS, MP or LOS/MP may involve deriving an expression for the probability density function (PDF), probability mass function (PMF), or other statistical or probabilistic function as they relate to various numbers of occupants. In other examples, mathematical analysis can involve other spatio-temporal analysis (mathematical analysis of multiple links over space and time) or other probabilistic spatio-temporal analysis (probabilistic analysis of multiple links over space and time) of the RSSI data. In some examples, the analysis makes use of modeling occupant behavior within the area. In one example, for instance, the speed or average speed of occupants may be assumed and used in the mathematical modeling. In another example, any knowledge of spatial preferences or popular areas can be used in the mathematical modeling. Theoretical models generated are stored, for example in a memory unit (not shown) and subsequently compared to the generated RSSI data for occupancy count in the real time. 
     As discussed above, in one implementation, the processing circuitry  216  compares the generated RSSI data from the plurality of receivers in real time with thresholds or the like produced by the mathematical model. More particularly, in one implementation, the processing circuitry  216  analyzes the generated RSSI data to derive a probability density function (PDF) or probability mass function (PMF) representation of the generated RSSI data that can be compared with the statistical or probabilistic functions derived for the theoretical models as described above. In one implementation, the processing circuitry  216  determines a best match between the PDF/PMF representation of the generated RSSI data in real time and the theoretical or modeled attributes (or functions of the modeled attributes). A variety of methods may be utilized to find the best match or fit between the function describing the RSSI data generated in real time and the function describing the theoretical (modeled) attributes, such as Kullback-Leibler (KL) divergence. 
     As discussed above, in another implementation, the processing circuitry  216  processes the generated RSSI data utilizing a heuristic algorithm to determines an occupancy count in the area  105 . The processing circuitry applies the heuristic algorithm to the indicator data of the RF signals from each of the plurality of receivers to compute an output metric value for each of a plurality of probable number of occupants in the area. The processing circuitry  216  also compares each one of the plurality of computed output metric values with another one of the plurality of computed output metric values to identify one of the plurality of computed output metric values as having a largest value indicates that the probable number of occupants associated with the computed metric value having the larges value is the current estimate of the occupancy count in the area  105 . Details of the utilizing of the heuristic algorithm are provided herein below. 
     As discussed above, in one implementation that takes advantage of the machine learning (ML) capability of the heurist algorithm, the system  250  includes a trusted detector  230 , which provides a known occupancy count value (similar to the “known answer” as discussed above). Input from the trusted detector  230  enables the processor or the like running the heuristic algorithm to “learn” which outcomes are accurate versus outcomes that are not accurate, so as to improve performance. The trusted detector  230  in the example may be a standard occupancy sensor, such as passive infrared occupancy detector or a camera based occupancy counting system. Specifically, the trusted detector  230  provides a known occupancy count value for an accurate occupancy count in the area  105  at each of the multiple times. In one implementation, the known occupancy count value is pre-determined prior to heuristically determining the occupancy count in the area  105 . 
     In one implementation, the processing circuitry  216  obtains the indicator data of the RF signal (transmitted by T 1  and T 2 ) generated for multiple times (ta-tn) from the R 1 . The processing circuitry  216  applies one of a heuristic algorithm coefficient among a set of heuristic algorithm heuristic algorithm coefficients to each of the indicator data from the R 1  to generate an indicator data metric value for each of the indicator data from the R 1  and R 2  for the times ta-tn. Each heuristic algorithm coefficient among the set of heuristic algorithm coefficients may be randomly selected at an initial stage of training. In one implementation, a heuristic algorithm coefficient is a variable. In one implementation, the processing circuitry  216  processes the indicator data metric values to compute metric values associated with the R 1  at each of the times ta-tn. The metric values provide a measurement of each of a plurality of a probable or possible number of occupants in the area for each of the times ta-tn. Some examples of the measurements may include but not limited to percentage, decimal, ratio, rates etc. In one implementation, the processing circuitry  216  combines/adds the metric values associated with R 1  to compute an output metric value for each of the plurality of probable number of occupants in the area for each of the times ta-tn. In one implementation, the processing circuity  216  compares each of the plurality of output metric values with one another to determine which of the plurality of output metric values has the highest value. The processing circuitry  216  determines that the probable number of occupants in the area with the largest output metric value as the occupancy count in the area for each of the times ta-tn. In one implementation, the processing circuitry  216  compares the occupancy count in the area with the known occupancy count value generated by the trusted detector for each of the ta-tn. Specifically, the processing circuitry  216  compares the occupancy count in the area at each of the ta-tn with the known occupancy count value, for example, an output of the trusted detector  230 , to determine an accurate occupancy count in the area as described in greater detail below. In in one implementation, the system  250  includes a learning module  220  coupled to the processing circuitry  216  to determine whether the set of heuristic algorithm coefficients are optimized heuristic algorithm coefficients based on the comparison by the processing circuitry  216  at the times ta-tn to detect an accurate occupancy count in the area. In one implementation, upon determination, that the set of heuristic algorithm coefficients are optimized heuristic algorithm coefficients, the learning module  220  instructs the processing circuitry  216  to utilize the optimized heuristic algorithm coefficients in real time. In one implementation, upon determination, that the set of heuristic algorithm coefficients are not optimized heuristic algorithm coefficients, the learning module  220  instructs the processing circuitry  216  to update one or more heuristic algorithm coefficients among the set of heuristic algorithm coefficients and utilize the updated one or more heuristic algorithm coefficients in a next time. The above implementations are described in greater detail below. 
     As discussed above, in one implementation, the processing circuitry  216  determines that the occupancy count at a time t 1  among the times ta-tn is same as the known occupancy count value. In one implementation, the learning module  220  determines, that the set of heuristic algorithm coefficients are determined to be optimized heuristic algorithm coefficients to be applied to the indicator data for the time t 1  to determine the accurate occupancy count. In one implementation, the learning module  220  instructs the processing circuitry  216  to utilize the optimized heuristic algorithm coefficients to apply the indicator data from the receiver for the time t 1  to detect the occupancy count in real time. Accordingly, the processing circuitry  216  applies the optimized heuristic algorithm coefficients to determine the occupancy count in real time. 
     As discussed above, in another implementation, the processing circuitry  216  determines that the occupancy count at a time t 1  among the times ta-tn is different than the known occupancy count value. The learning module  220  determines that the set of heuristic algorithm coefficients are not optimized heuristic algorithm coefficients and thus updates the one or more heuristic algorithm coefficients among the set of the heuristic algorithm coefficients to generate updated set of heuristic algorithm coefficients. The learning module  220  instructs the processing circuitry  216  to utilize the updated set of heuristic algorithm coefficients in a next time. The processing circuitry  216  applies the updated heuristic algorithm coefficients to corresponding indicator data from the R 1  to generate an updated indicator data metric value for the indicator data from the R 1  at the time t 1 . In one implementation, the processing circuitry  216  processes the updated indicator data metric values to compute updated occupancy count at t 1 . In one implementation, the processing circuitry  216  determines that the updated occupancy count at the time t 1  is the same as the known occupancy count value. As such, the learning module  220  determines that the updated set of heuristic algorithm coefficients are optimized heuristic algorithm coefficients to be applied to the indicator data for the time t 1  to determine the accurate occupancy count in real time. In another implementation, the processing circuitry  216  determines that the updated occupancy count is different than the known occupancy count value. The processing circuitry  216  and the learning module  220  repeats the above process for t 1  until the occupancy count is same as the known occupancy count value to determine that the set of heuristic algorithm coefficients corresponding to the indicator data from the R 1  are the optimized heuristic algorithm coefficients for the t 1  among the ta-tn to accurately determine the occupancy count at real time. Accordingly, the processing circuitry  216  applies the optimized heuristic algorithm coefficients to determine the occupancy count in real time. 
     In one implementation, the occupancy count is determined for the indicator data at each of the ta-tn and compared with the known occupancy count value to determine the optimized heuristic algorithm coefficients for each of the ta-tn to detect an accurate occupancy count in the area  105  of  FIG.  1 B  at each of the ta-tn. In one implementation, the optimized set of heuristic algorithm coefficients for each of the ta-tn are utilized by the processing circuitry  216  to detect accurate occupancy count in the area  105  of  FIG.  1 B  at real time. 
     Referring to  FIG.  2 E , there is shown a functional block diagram of an example of an occupancy counting system (system)  251  configured to function on a radio frequency (RF) wireless communication network. In one implementation, the system  251  is similar to the system  250  of  FIG.  2 D  except the processing circuitry  216  is coupled to the one or more of the lighting elements via a network  240 . In one implementation, the network  240  is a wireless communication network. In one example, the network  240  is a BLE mesh. In one implementation, the network  240  is a wired network. In one implementation, the processing circuitry  216  is a cloud computing system which includes a plurality of processing servers/machines, which work together or independently to process the indicator data to determine the occupancy count in the area  105 . In an alternate implementation, the controller  218  is coupled to the processing circuitry  216  via the network  240 . In such alternate implementation, the controller  218  is a cloud computing system which includes a plurality of processing servers/machines, which work together or independently to control operations of one or more elements (e.g. light source  206   a - 206   n ) of the lighting elements  202   a - 202   n , and to provide automation of other energy control, equipment control, operational control and management systems (e.g. HVAC, heat mapping, smoke control, equipment control and security control) in the area upon the occupancy count determined by the processing circuitry  216  as well as other automation control of energy, equipment, operational and management, as discussed above, of the area based on determination of the occupancy count by the processing circuitry  216 . Accordingly, implementation of the system  251  is configured to globally control the light source(s) of the lighting element(s), as well as other automation control of energy, equipment, operational and management, as discussed above, of the area. 
     Referring to  FIG.  2 F , there is shown a functional block diagram of an example of an occupancy counting system (system)  252  configured to function on a radio frequency (RF) wireless communication network. In one implementation, the system  252  is similar to the system  250  of  FIG.  2 D  except the processing circuitry  216  is integrated in a lighting element  202 . The processing circuitry  216  functions to process the indicator data to determine the occupancy count in the area  105  as discussed in detail above. The system  252  also includes plurality of lighting elements  202   a - 202   n  including the lighting element  202 . Although, not illustrated, in an alternate implementation, the processing circuitry  216  is integrated in one of the plurality of lighting elements  202   a - 202   n . Each of the plurality of lighting elements includes a corresponding light source among a plurality of light sources  202   a - 202   n.    
     Referring to  FIG.  3   , an example of a wireless topology  301  of a lighting system includes a number of wireless communication transmitters (Tx) and a number of wireless communication receiver (Rx) in physical space/area  305 . In one implementation, indoor environment is described, but it should be readily apparent that the systems and methods described herein are operable in external environments as well. Specifically, in this example, the area  305  includes a combination of a room  360 , and a hallway  380 . In one implementation, although, not shown, the area  305  may also include corridors, additional rooms, additional hallways etc. In one implementation, although, not shown, the area  305  may also include corridors, additional rooms, hallways etc. 
     A wall  390  separates the room  360  from the hallway  380  with an opening  392 . As illustrated in the example in  FIG.  3   , the area  305  includes six intelligent system nodes  332 ,  334 ,  336 ,  338 ,  340 , and  342 . Each such system node has an intelligence capability to transmit a signal or receive a signal and process data. In one example, at least one system node includes a light source and is configured as a lighting device or luminaire. In another example, a system node includes a user interface component and is configured as a lighting controller. In another example a system node includes a switchable power connector and is configured as a plug load controller. In a further example a system node includes detector as well as related circuitry and is configured as a lighting related sensor. 
     In general, a heuristic algorithm with prior or ongoing training for machine learning, “learns” how to manipulate various inputs, possibly including previously generated outputs, in order to generate current new outputs. As part of this learning process, the algorithm receives feedback on prior outputs and possibly some other inputs. Then, the machine learning algorithm calculates parameters to be associated with the various inputs (e.g. the previous outputs, feedback, etc.). The parameters are then utilized by the machine learning to manipulate the inputs and generate the current outputs intended to improve some aspect of system performance in a desired manner. During the machine learning phase, the training data is the discrepancy between the outputs of a present system and the outputs of a trusted system. 
     In a lighting system with occupancy count, for example, the training data may be the discrepancy between the outputs of an RF based detection system operating in a user/consumer installation and a trusted occupancy count system such as a standard occupancy sensor (e.g. such as a sensor using passive infrared (PIR) of or a camera based system). Machine learning techniques such as artificial neural network is applied to reduce the discrepancy, or example, by optimizing one or more heuristic algorithm coefficients used in the real time occupancy count. Training can take place ahead of the time (before product shipment/commissioning) or in the field as an on-going optimization to reduce false positives in counting occupant(s). 
     An example may apply a “supervised learning” approach in which the system will be provided a “known answer” from a “trusted detector” and machine learning is used to optimize the occupancy count algorithm to minimize the difference between the system output and the “known answer.” A trusted detector may be a passive infrared occupancy detector or a camera. The particular machine learning approach can be one of decision tree or artificial neural net. 
     Learning can take place prior to shipping product or as part of commissioning after installation. In either such case, the system may normally operate in the field without using the trusted detector in real time. 
     Alternatively, a trusted detector can be installed with the system in the field and utilized in real time, in which case, there may be on-going machine learning. For an ongoing learning implementation, the data can be routed to a cloud, learning can take place on another system, and then the improved algorithm (e.g. in the form of new node parameters in the case of a neural network) can be downloaded to the installed lighting system. 
     In one implementation, details of the heuristic algorithm and machine learning are provided in more detail with respect to the example of  FIG.  3   . 
     System nodes  332 ,  334 ,  136  and  138  are located in the room  360  and the system nodes  340  and  342  are located in the hallway  380 . Each of the system nodes  332 ,  334  and  336  include transmitters T 1 , T 2  and T 3  respectively and each of the system nodes  338 ,  340  and  342  include receivers R 1 , R 2  and R 3  respectively. In one implementation, the occupancy count in the entire area  305  and/or a region (for example room  360 ) in the area  305  is detected according to a ML occupancy counting procedure as will be described below with respect to  FIGS.  4 A,  4 B and  4 C . 
     In the wireless topology  301  each of the transmitters T 1 -T 3  in the area  305  transmits a RF spectrum (RF) signal for some number (plurality &gt;1) of times. The transmissions from T 1 -T 3  may be specifically for the occupancy count, although the present teachings also apply to implementations using the RF wireless transmissions for other purposes, such as system network communications (as discussed later regarding other examples. Each of the receivers R 1 -R 3  in the area  305  receives the transmissions of the RF signal through the area  305  for each of the plurality of times from each of the multiple T 1 -T 3 . Logically, such a three transmitter-three receiver arrangement provides nine T-R pairings for the analysis (each of the three transmitters T 1 -T 3  each paired logically with each of the three receivers R 1 -R 3 ). Accordingly, each of the R 1 -R 3  is configured to detect a metric of the received RF, which the system (e.g. at one or more nodes or another processor in communication with the receivers) uses to count occupant(s) in its own region (room  360  or the hallway  380 ) based on receipt of the multiple RF signals received globally from the multiple T 1 -T 3  in the area  305 . 
     Thus, for example, a RF perturbation caused by a person in room  380  is detected by the T 1 /R 1  and T 2 /R 2  (in the room  360 ), each of which generates a signal indicator data for the heuristic analysis. A person in the room  360  can also trigger a response in the hallway  390  detected by the T 3 /R 3  in the hallway  380 , but at a lower signal level. A signal level threshold may be used to reject the false positive in the hallway  390 . A similar threshold approach may be implemented to prevent false positives at the nodes i.e. T 3 /R 3  in the hallway  390 . 
     In one example, it is desired to determine an occupancy count in the room  380 . The heuristic algorithm is configured to processing indicator data from R 1  and R 2  to detect one of an inaccurate occupancy count in the room  380  since each of R 1  and R 2  receives RF signals not only from the T 1  and the T 2  in the room  380  but also receives RF signals from the T 3  in the hallway  180 . Accordingly, the heuristic algorithm is applied to allow processing of indicator data from the R 1  and R 2  in the room  160  to ignore/eliminate the RF signals received from the R 3 , which are generated by the T 3  due to the presence of the number of occupants in the hallway  380  and/or multipath returns of signals generated by the T 1  and T 2  in the room  180  but received due to or modified by the presence of number of occupants in the hallway  380 . In one implementation, the occupancy count in the room  360  is detected according to a ML occupancy counting procedure as will be described below with respect to  FIGS.  4 A,  4 B and  4 C . 
     Referring to  FIG.  4 A , there is shown a functional block diagram of an example of a heuristic occupancy counting system  400  configured to function on a radio frequency (RF) wireless communication network. As illustrated, the heuristic occupancy counting system  400  includes a plurality of lighting elements  402   a - 402   n  in the physical space/area  305  such as a room and a hallway etc. as described above with respect to  FIG.  3   . In one implementation, an indoor environment is described, but it should be readily apparent that the systems and methods described herein are operable in external environments as well. 
     In one implementation, the system  402  includes the six intelligent system nodes  332 ,  334 ,  336 ,  338 ,  340 , and  342  as described with respect to  FIG.  3    above. As discussed above, each such system node has an intelligence capability to transmit and receive data and process the data. Each system node, for example, may include a receiver (R) and/or a transmitter (T) along with another component used in lighting operations. In one example, a system node includes a light source and is configured as a lighting device. In another example, a system node includes a user interface component and is configured as a lighting controller. In another example the system node includes a switchable power connector and is configured as a plug load controller. In a further example, a system node includes a detector as well as related circuitry and is configured as a lighting related sensor. The system nodes  332 ,  334 , and  336  include T 1 , T 2  and T 3  respectively; and the system nodes  338 ,  340  and  342  include R 1 , R 2  and R 3  respectively. 
     In the implementation shown in  FIG.  4 A , each of the system nodes  332 ,  334 ,  336 ,  338 ,  340  and  342  is integrated in one of the lighting elements  402   a - 402   n  such that the system node  332  is integrated in the lighting element  402   a , the system node  334  is integrated in the lighting element  402   b , the system node  336  is integrated in the lighting element  402   c  the system node  338  is integrated in the lighting element  402   d  the system node  340  is integrated in the lighting element  402   e  the system node  342  is integrated in the lighting element  402   n . Even though, the system nodes  332 ,  334 ,  336 ,  338 ,  340  and  342  are shown to be integrated in the lighting elements  202   a ,  402   b  and  402   c ,  402   d ,  402   e  and  402   n  respectively, it should be apparent that the system nodes  332 ,  334 ,  336 ,  338 ,  340  and  342  are integrated in different lighting devices among the lighting devices  402   a - 402   n . In another alternate implementation, two or more of the system nodes  332 ,  334 ,  336 ,  338 ,  340  and  342  may be integrated in the same lighting element. For example, the system node  332  and the system node  338  may both be incorporated in the lighting element  402   a  or in another example, the system node  334  and the system node  340  may both be incorporated in the lighting element  402   b.    
     As described above, the Tx is configured to transmit RF signals and each of the Rx is configured to receive signals from each Tx. In one implementation, each of the lighting elements  402   a - 402   n  includes a light source  406 , and a system node containing the source  206  or coupled to and operation together with the source  406  and is configured as a luminaire, for example, may take the form of a lamp, light fixture, or other luminaire that incorporates the light source, where the light source by itself contains no intelligence or communication capability, such as one or more LEDs or the like, or a lamp (e.g. “regular light bulbs”) of any suitable type. The light source  406  is configured to illuminate some or all of the area  405 . In one example, each of some number of individual the light sources  406  is configured to illuminate a portions or a regions of the area  405 . Typically, a lighting system will include one or more other system nodes, such as a wall switch, a plug load controller, or a sensor. 
     In one implementation, the system  400  includes processing circuitry  416  coupled to the receivers R 1  and R 2 . In one implementation, the processing circuitry is coupled to one or more of the lighting elements  402   a - 402   n . In an alternate implementation, the processing circuitry  416  is coupled to the system  400  via a network (not shown). In one implementation, the processing circuitry  416  is implemented in a processor executing software or firmware of configured to determine occupancy count in the area  305  or the region (for example, room  360 ) in the area  305 , although other circuitry or processor-based implementations may be used. In one implementation, the processing circuitry  216  is implemented in firmware of a processor in or more of the R 1  node, R 2  node or R 3  node. 
     In one implementation, the system  400  includes a controller  418  coupled to the processing circuitry  416 . In one implementation the controller  418  may be the same or an additional processor configured to control operations of elements in the system  400  in response to determination of occupancy count in the area  305  or a region (for example, room  360 ) in the area  305 . For example, in an alternate implementation, the controller  418  is configured to process a signal to control operation of one or more light sources  406   a - 406   n . In one alternate implementation, the controller  418  is configured to turn ON one or more light sources  406   a - 406   n  upon the occupancy count of one or more determined by the processing circuitry  416 . In one implementation, the controller  418  is configured to turn OFF one or more light sources  406   a - 406   n  upon the occupancy count of zero determined by the processing circuitry  416 . In another implementation, upon the occupancy count in the area  305 , the controller  418  may be configured to provide other control and management functions in the area such as heating, ventilation and air conditioning (HVAC), heat mapping, smoke control, equipment control, security control, etc. instead of or in addition to control of the light source(s). Accordingly, the system  400  is configured to function on the RF wireless communications network in accordance with an implementation of a local control of light source(s) in the lighting element(s), as well as other automation control of energy, equipment, operational and management, as discussed above, of the area. 
     In yet another implementation, the controller  418  communicates the occupancy count to the lighting network via a data packet. The data packet is received by one or more luminaires in the lighting network, which are configured to turn ON or OFF the light source(s)  406  and/or in the luminaire or another network node to provide automation of other energy control, equipment control, operational control and management systems (e.g. HVAC, heat mapping, smoke control, equipment control, security control) in the area  105  based on the occupancy count provided in the data packet. Accordingly, the system  400  communicates the occupancy count with other networks. In another alternate implementation, the controller  418  is coupled to the system  400  via a network (not shown). Accordingly, the system  400  is configured to function on the RF wireless communication network in accordance with an implementation of a global control of light source(s) in lighting element(s), as well as other automation control of energy, equipment, operational and management, as discussed above, of the area in a lighting system. 
     In one implementation, the system nodes typically include a processor, memory and programming (executable instructions in the form of software and/or firmware). Although the processor may be a separate circuity (e.g. a microprocessor), in many cases, it is feasible to utilize the central processing unit (CPU) and associated memory of a micro-control unit (MCU) integrated together with a transceiver in the form of a system on a chip (SOC). Such an SOC can implement the wireless communication functions as well as the intelligence (e.g. including any processing or controller capabilities) of the system node. 
     In examples discussed in more detail later, system nodes often may include both a transmitter and a receiver (sometimes referenced together as a transceiver), for various purposes. At times, such a transceiver-equipped node may use its transmitter as part of a heuristic occupancy sensing operation; and at other times such a transceiver-equipped node may use its receiver as part of a heuristic occupancy counting operation. Such transceiver equipped nodes also typically include a processor, memory and programming (executable instructions in the form of software and/or firmware). Although the processor may be a separate circuity (e.g. a microprocessor), in many cases, it is feasible to utilize the central processing unit (CPU) and associated memory of a micro-control unit (MCU) integrated together with physical circuitry of a transceiver in the form of a system on a chip (SOC). Such an SOC can implement the wireless communication functions as well as the intelligence (e.g. including any processing or controller capabilities) of the system node. 
     Although the system nodes  332 - 342  of  FIG.  4 A  illustrate an implementation of a single Tx and a single Rx in each of the nodes, the system  400  may include other implementations such as multiple Txs in one or more nodes. Also,  FIG.  4 A  illustrates the implementation of a single Rx in each of the nodes, the system  400  may include other implementations such as multiple Rx in one or more nodes. In the illustrated implementation, the system  400  includes multiple lighting elements  406   a - 406   n  with either the Tx or the Rx, however, the multiple lighting elements  406   a - 406   n  of the system  400  may include one or more Tx and one or more Rx (see  FIG.  7   ). 
     For discussion of an initial example of a heuristic RF-based occupancy counting operation, assume that the system  400  includes just the elements shown in  FIG.  4 A . In one example, each of the system nodes  332 - 342  includes the capabilities to communicate over two different RF bands, although the concepts discussed herein are applicable to devices that communicate with luminaires and other system elements via a single RF band. Hence, in the dual band example, the Tx/Rx may be configured for sending and receiving various types of data signals over one band, e.g. for the RF transmission and reception leading to occupancy counting. The other band may be used or for pairing and commissioning messages over another band and/or for communications related to detection of RF or higher level occupancy counting functions, e.g. between receivers R 1  and R 2  and the controller  420  or the processing circuitry  416 . For example, the Tx and Rx are configured as a 900 MHz transmitter and receiver for communication of a variety of system or user data, including lighting control data, for example, commands to turn light son/OFF, dim up/down, set scene (e.g., a predetermined light setting), and sensor trip events. Alternatively, the Tx and Rx may be configured as a 2.4 GHz transmitter and receiver for Bluetooth low energy (BLE) communication of various messages related to commissioning and maintenance of a wireless lighting system and/or to communicate results of processing functions in relation to occupant counting. 
     In one implementation, benefits of the system include the ability to take advantage of Tx and the Rx (e.g. RF Tx and RF Rx) already installed in a location in the area  305 , and because the system passively monitors signal broadcasts in the area  305  at a plurality of times, the heuristic occupancy counting functionality does not require (does not rely on) the occupants to carry any device. 
     At a high level, the T 1  transmits a RF spectrum (RF) signal at a plurality of times. The transmission may be specifically for the occupancy counting. In some cases, however, where the transmitter is in another lighting device or other lighting system element (e.g. a sensor or a wall switch), the transmissions maybe regular lighting related communications, such as reporting status, sending commands, reporting sensed events, etc. Each of the R 1 -R 3  receives the transmissions of the RF signal from each of the T 1 -T 3  through the area  305  during each of the plurality of times. Each of the R 1 -R 3  generates an indicator data of one or more characteristics of the received RF signal at each of the plurality of times. Some of examples of the characteristics include but are not limited to received signal strength indicator (RSSI) data, bit error rate, packet error rate, phase change etc. or a combination of two or more thereof. The RSSI data represents measurements of signal strength of the received RF. The bit error rate is rate of incorrect bits in received RF signals versus total number of bits in the transmitted RF signals. The packet error rate is rate of incorrect packets in received RF signals versus total number of packets the transmitted RF signals. Phase change is a change of phase of a received RF signal compared to previous reception of the RF signal (typically measured between the antennas spaced apart from each other). For the purpose of the present description, we use RSSI data as the characteristics of the RF signal for processing by each of the R 1 -R 3  receives to generate as the indicator data. Each of the R 1 -R 3  measures the signal strength of the RF signal received from transmitter T 1  and generates the RSSI data based on the signal strength. The signal strength of each of the RF signal varies over time based whether an occupant exists or there are a number of occupants in a path between each of the T 1 -T 3  and each of the R 1 -R 3  in the area  305 . 
     For each time, each of the receivers R 1 -R 3  supplies the generated indicator data of one or more characteristics of the received RF signal to the processing circuitry  316 . In one implementation using RSSI as the characteristic of interest, the processing circuitry  316  obtains the generated RSSI data at each of the plurality of times from the various receivers R 1 -R 3  and utilizes a heuristic algorithm to determine occupancy count in the area  305  or the region (for example, room  360 ) in the area  305  as described in greater detail herein below. 
     In one implementation, that takes advantage of the machine learning (ML) capability of the heurist algorithm, the system  400  includes a trusted detector  430 , which provides a known occupancy count value (similar to the “known answer” as discussed above). Input from the trusted detector  430  to “learn” so as to improve performance. The trusted detector  430  in the example may be a standard occupancy sensor, such as passive infrared occupancy detector or a camera based occupancy counting system. Specifically, the trusted detector  430  provides a known occupancy count value for an accurate occupancy count in the area  305  or the region (for example, room  360 ) in the area  305  at each of the multiple times. In one implementation, the known occupancy count value is pre-determined prior to heuristically determining the occupancy count in the area  305  or the region (for example, room  360 ) in the area  305 . 
     In one implementation, the processing circuitry  416  obtains the indicator data of the RF signal generated for multiple times (ta-tn) from each of the R 1 -R 3 . The processing circuitry  416  applies one of a heuristic algorithm heuristic algorithm coefficient (heuristic algorithm coefficient) among a set of heuristic algorithm heuristic algorithm coefficients to each of the indicator data from each of the R 1 -R 3  to generate an indicator data metric value for each of the indicator data from each of the R 1 -R 3  for the times ta-tn. Each heuristic algorithm coefficient among the set of heuristic algorithm coefficients may be randomly selected at an initial stage of training. In one implementation, a set of heuristic algorithm coefficients are utilized to determine count in the entire area  305 . In one implementation, a different set of heuristic algorithm coefficients are utilized to determine the occupancy count in the sub-area (example, room  360 ) of the area  305 . As such, the different set of heuristic algorithm coefficients are selected to reject false positives such as transmission signals from T 3  and received signals from R 3  that are not part of the room  360 . In one implementation, the heuristic algorithm is trained using the appropriate set of heuristic algorithm coefficients to determine the occupancy count in the entire area  305  or the sub-area of the area, for example, the room  360 . As discussed above, training can take place ahead of the time (before product shipment/commissioning) or in the field as an on-going optimization to reduce false positives in determining an occupant count. Also as discussed above, the training is executed by the trusted detector. Accordingly, the occupancy count as discussed below with respect to the area may include the entire area  305  or a sub-area (example room  360 ) of the entire area  305 . 
     In one implementation, a heuristic algorithm coefficient is a variable. In one implementation, a value of a heuristic algorithm coefficient applied to an indicator data from R 1  is the same as a value of a heuristic algorithm coefficient applied to another indicator data that is from R 2 . In another implementation, a value of a first heuristic algorithm coefficient applied to an indicator data from the R 1  is different from value of another (second) heuristic algorithm coefficient applied to another indicator data from R 2 . In one implementation, the processing circuitry  416  processes the indicator data metric values to compute metric values associated with each of the R 1  and R 2  at each of the times ta-tn. The metric values provide a measurement of each of a plurality of a probable or possible number of occupants in the area for each of the times ta-tn. Some examples of the measurements may include but not limited to percentage, decimal, ratio, rates etc. In one implementation, the processing circuitry  416  combines/adds the metric values associated with R 1  with metric values associated with R 2  and the metric values associated with R 3  to compute an output metric value for each of the plurality of probable or possible number of occupants in the area for each of the times ta-tn. In one implementation, the processing circuity  416  compares each of the plurality of output metric values with one another to determine which of the plurality of output metric values has the highest value. The processing circuitry  416  determines that the probable number of occupants in the area with the largest output metric value as the occupancy count in the area for each of the times ta-tn. In one implementation, the processing circuitry  416  compares the occupancy count in the area with the known occupancy count value generated by the trusted detector for each of the ta-tn. Specifically, the processing circuitry  416  compares the occupancy count in the area at each of the ta-tn with the known occupancy count value, for example, an output of the trusted detector  430  to determine an accurate occupancy count in the area as described in greater detail below. In one implementation, the system  400  includes a learning module  420  coupled to the processing circuitry  416  to determine whether the set of heuristic algorithm coefficients are optimized heuristic algorithm coefficients based on the comparison by the processing circuitry  416  at the times ta-tn to detect an accurate occupancy count in the area. In one implementation, upon determination, that the set of heuristic algorithm coefficients are optimized heuristic algorithm coefficients, the learning module  420  instructs the processing circuitry  416  to utilize the optimized heuristic algorithm coefficients in real time. In one implementation, upon determination, that the set of heuristic algorithm coefficients are not optimized heuristic algorithm coefficients, the learning module  420  instructs the processing circuitry  416  to update one or more heuristic algorithm coefficients among the set of heuristic algorithm coefficients and utilize the updated one or more heuristic algorithm coefficients in a next time. The above implementations are described in greater detail below. 
     In one implementation, the processing circuitry  416  determines that the occupancy count at a time t 1  among the times ta-tn is same as the known occupancy count value. In one implementation, the learning module  420  determines, that the set of heuristic algorithm coefficients are determined to be optimized heuristic algorithm coefficients to be applied to the indicator data for the time t 1  to determine the accurate occupancy count. In one implementation, the learning module  420  instructs the processing circuitry  416  to utilize the optimized heuristic algorithm coefficients to apply to each indicator data among the plurality of indicator data from each of the plurality of receivers for the time t 1  to detect the occupancy count in real time. Accordingly, the processing circuitry  416  applies the optimized heuristic algorithm coefficients to determine the occupancy count in real time. 
     In another implementation, the processing circuitry  416  determines that the occupancy count at a time t 1  among the times ta-tn is different than the known occupancy count value. The learning module  420  determines that the set of heuristic algorithm coefficients are not optimized heuristic algorithm coefficients and thus updates the one or more heuristic algorithm coefficients among the set of the heuristic algorithm coefficients to generate updated set of heuristic algorithm coefficients. The learning module  420  instructs the processing circuitry  416  to utilize the updated set of heuristic algorithm coefficients in a next time. The processing circuitry  416  applies the updated heuristic algorithm coefficients to corresponding indicator data from each of the R 1 -R 3  to generate an updated indicator data metric value for each of the indicator data from each of the R 1 -R 3  at the time t 1 . In one implementation, the processing circuitry  416  processes each of the updated indicator data metric values to compute updated occupancy count at t 1 . In one implementation, the processing circuitry  416  determines that the updated occupancy count at the time t 1  is the same as the known occupancy count value. As such, the learning module  420  determines that the updated set of heuristic algorithm coefficients are optimized heuristic algorithm coefficients to be applied to the indicator data for the time t 1  to determine the accurate occupancy count in real time. In another implementation, the processing circuitry  416  determines that the updated occupancy count is different than the known occupancy count value. The processing circuitry  416  and the learning module  420  repeats the above process for t 1  until the occupancy count is same as the known occupancy count value to determine that the set of heuristic algorithm coefficients corresponding to the indicator data from each of the R 1 -R 3  are the optimized heuristic algorithm coefficients for the t 1  among the ta-tn to accurately determine the occupancy count at real time. Accordingly, the processing circuitry  416  applies the optimized heuristic algorithm coefficients to determine the occupancy count in real time. 
     In one implementation, the occupancy count is determined for each of the indicator data at each of the ta-tn and compared with the known occupancy count value to determine the optimized heuristic algorithm coefficients for each of the ta-tn to detect an accurate occupancy count in the area  305  or the region (for example, room  360 ) in the area  305  of  FIG.  3    at each of the ta-tn. In one implementation, the optimized set of heuristic algorithm coefficients for each of the ta-tn are utilized by the processing circuitry  416  to detect accurate occupancy count in the area  305  or the region (for example, room  360 ) in the area  305  of  FIG.  3    at real time. 
     Referring to  FIG.  4 B , there is shown a functional block diagram of an example of a heuristic occupancy counting system (system)  401  configured to function on a radio frequency (RF) wireless communication network. In one implementation, the system  401  is similar to the system  400  of  FIG.  4 A  except the processing circuitry  416  is coupled to the one or more of the lighting elements via a network  440 . In one implementation, the network  440  is a wireless communication network. In one example, the network  440  is a BLE mesh. In one implementation, the network  440  is a wired network. In one implementation, the processing circuitry  416  is a cloud computing system which includes a plurality of processing servers/machines, which work together or independently to process the indicator data to determine the occupancy count in the area  305  or the region (for example, room  360 ) in the area  305 . In an alternate implementation, the controller  418  is coupled to the processing circuitry  416  via the network  440 . In such alternate implementation, the controller  418  is a cloud computing system which includes a plurality of processing servers/machines, which work together or independently to control operations of one or more elements (e.g. light source  406   a - 406   n ) of the lighting elements  402   a - 402   n  and/or provide automation of other energy control, equipment control, operational control and management systems (e.g. HVAC, heat mapping, smoke control, equipment control, security control) in the area  105  based on determination of the occupancy count by the processing circuitry  416 . Accordingly, implementation of the system  201  is configured to globally control the light source(s) of the lighting element(s) as well as other automation control of energy, equipment, operational and management, as discussed above, of the area. 
     Referring to  FIG.  4 C , there is shown a functional block diagram of an example of a heuristic occupancy counting system (system)  402  configured to function on a radio frequency (RF) wireless communication network. In one implementation, the system  402  is similar to the system  400  of  FIG.  4 A  except the processing circuitry  416  is integrated in a lighting element  402 . The processing circuitry  416  functions to process the indicator data to determine the occupancy count in the area  305  or the region (for example, room  360 ) in the area  305  as discussed in detail above. The system  402  also includes plurality of lighting elements  407   a - 407   n  including the lighting element  402 . Although, not illustrated, in an alternate implementation, the processing circuitry  416  is integrated in one of the plurality of lighting elements  407   a - 407   n . Each of the plurality of lighting elements includes a corresponding light source among a plurality of light sources  407   a - 407   n.    
     In one implementation, the processing circuitry  416  includes a neural network as a training method to determine occupancy count of one of the area  105  of  FIG.  1  or  305    of  FIG.  3   . Referring to  FIG.  5   , there is shown an example of a neural network  500 . The neural network  500  includes an input layer  502  of input nodes  502   a - 502   i , at least one middle layer  504  of middle nodes  504   a - 504   j  and an output layer  510  of output nodes  510   a - 510   n . Although, the middle layer  504  includes ten nodes, it is known to one of ordinary skill that the middle layer  504  may include any number of nodes, the number likely to be larger than the number of input nodes. Even though only one middle layer is shown, it known to one of ordinary skill in the art that more than one middle layer of nodes may be implemented in the neural network  500 . As shown, each of the input nodes  504   a - 504   i  is coupled to each of the middle nodes  504   a - 504   j  and each of the middle nodes  504   a - 504   j  is coupled to each of the output nodes  510   a - 510   n . In one implementation, each of the middle nodes  504   a - 504   j  in the middle layer  504  includes a corresponding bias constant ba-bi unique to that node. The bias constants ba-bi are initially randomly assigned. In one implementation, each connection from each of the input nodes  502   a - 502   i  to each of the middle nodes  504   a - 504   j  includes a corresponding weight (Wa-Wi) unique to the connection. The weights Wa-Wi are initially randomly assigned. In one implementation, the bias constants ba-bi and the weights Wa-Wi are the plurality of heuristic algorithm coefficients as described above. 
     The input layer of nodes  502   a - 502   i  includes the RSSI data R 11 , R 12 , R 13 , R 21 , R 22 , R 23 , R 31 , R 32  and R 33 . Specifically, input node  502   a  includes R 11 , input node  502   b  includes R 12 , input node  502   c  includes R 13 , input node  502   d  includes R 21 , input node  502   e  includes R 22 , input node  502   f  includes R 23 , input node  502   g  includes R 31 , input node  502   h  includes R 32 , and input node  502   i  includes R 33 . As such, number of input nodes in the input layer of nodes  502   a - 502   i  is equal to number of RSSI data R 11 , R 12 , R 13 , R 21 , R 22 , R 23 , R 31 , R 32  and R 33 . In one implementation, a forward propagation including propagation function and an activation function is executed in the neural network as described herein below. 
     An output of each of the input nodes  502   a - 502   i  is an input to each of the middle nodes  504   a - 504   i  in the middle layer. In one implementation, the forward propagation includes a propagation function executed at each of the middle nodes,  504   a - 504   i  to generate propagation function values. Specifically, the propagation function is determined by multiplying each of the RSSI data, R 11 , R 12 , R 13 , R 21 , R 22 , R 23 , R 31 , R 32  and R 33  with its corresponding weight (W) among the Wa-Wi and added with its corresponding bias constant (b) among the ba-bi of each of the middle nodes  504   a - 504   i  resulting in a propagation value Za-Zi at each of the middle nodes  504   a - 504   i , which is summed together into a single propagation value Zj as shown below: 
     
       
         
           
             
               z 
               j 
               l 
             
             = 
             
               
                 
                   ∑ 
                   k 
                 
                 ⁢ 
                 
                   
                     w 
                     jk 
                     l 
                   
                   ⁢ 
                   
                     R 
                     k 
                     
                       l 
                       - 
                       1 
                     
                   
                 
               
               + 
               
                 b 
                 j 
                 l 
               
             
           
         
       
     
     The single propagation value Zj is fed into the activation function executed in each of the plurality of the output nodes  510   a - 510   n  resulting in an output metric value, aj for each of the output nodes  510   a - 510   n  as shown herein below:
 
 a   j   l   =f ( z   j   l )
 
     As discussed above, each of the output metric values represent the probable or possible number of occupants in the area. In one implementation, the output value is computed for each of the RSSI data at multiple times (ta-tn). In one implementation, each output metric value computed at each time among the multiple times (ta-tn) is compared with the known occupancy count value As discussed above, the known occupancy count value is a “known answer” computed from a trusted detector such as the passive infrared occupancy detector or a camera for each of the times among the multiple times (ta-tn). 
     In one implementation, the output metric values includes 40 percent for possibly 2 occupants in the area, 30 percent for possibly 4 occupants in the area, 20 percent for possible 7 occupants in the area and 10 percent for possible 10 occupants in the area for a time t 1  among the times ta-tn. Since the 40 percent is the highest percent, the occupancy count would be determined to be 2 in the area for the time t 1 . In one example, the known occupancy count value is 2 at the time t 1 . The processing circuitry  216  compares the known occupancy count value of 2 at the time tl with the occupancy count of 2 and since it is the same value the occupancy count of 2 is determined to be an accurate occupancy count in the area at the time t 1 . Accordingly, the corresponding weights Wa-Wi and the bias constants ba-bi are considered to be optimized heuristic algorithm coefficients and these optimized heuristic algorithm coefficients are utilized in the forward propagation as described above to detect an occupancy count in the area at real time. In another example, the known occupancy value is 4 at the time t 1 . The processing circuitry  216  compares the known occupancy count value of 4 at the time t 1  with the occupancy count of 2 and since it is a different value, the occupancy count of 2 is determined to be an inaccurate occupancy count in the area at the time t 1 . Accordingly, one or more weights Wa-Wi may be updated using a second gradient descent function as shown below: 
     
       
         
           
             
               w 
               jk 
               ′ 
             
             = 
             
               
                 w 
                 jk 
               
               - 
               
                 η 
                 ⁢ 
                 
                   
                     ∂ 
                     C 
                   
                   
                     ∂ 
                     
                       w 
                       jk 
                     
                   
                 
               
             
           
         
       
     
     Further, one or more bias constants ba-bi may be updated using the third gradient descent function as shown herein below: 
     
       
         
           
             
               b 
               j 
               ′ 
             
             = 
             
               
                 b 
                 j 
               
               - 
               
                 η 
                 ⁢ 
                 
                   
                     ∂ 
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                       b 
                       j 
                     
                   
                 
               
             
           
         
       
     
     W is the weight, b is the bias constant, n is the learning rate, C is the cost (loss) function. C is the difference between the computed output value and the true occupancy or non-occupancy value. C is minimized by taking the gradient with respect to the heuristic algorithm coefficients. In one implementation, a backward propagation function is applied to the neural network  500  using the one or more updated values of the weights, Wa-Wi and/or the one or more updated bias constants ba-bi. In one implementation, the backward propagation function includes providing the one or more updated values of the weights Wa-Wi and/or one or more updated bias constants ba-bi at each of the output nodes  510   a   410   n  and then cascading backwards towards the input node  502  by applying the one or more updated weights Wa-Wi and/or the one or more updated values of the bias constants ba-bi cascade backwards at each of the corresponding middle nodes  504   a - 504   j  in the middle layer  504  (including any additional middle nodes in additional middle layers not shown). 
     In one implementation, an updated occupancy count is generated for the t 1  with the one or more updated weights Wa-Wi and/or the one or more updated bias constants ba-bi using the forward propagation as described above. In one implementation, the updating of Wa-Wi using the second gradient function and/or of the ba-bi using the third gradient function as described above, backward propagation and the forward propagation are repeated until the occupancy count is determined to be of the same value as the known occupancy count value at the time t 1 . In one implementation, upon determination of the updated occupant count being equivalent to the known occupancy count value, the corresponding updated Wa-Wi and/or the updated ba-bi are utilized in the forward propagation as described above to determine the occupancy count in the area  105  and/or  305  at a real time. 
       FIG.  6 A  illustrates an example of a flowchart of a method  601  for a system level determination of an occupancy count for multiple times in area  105  of a system of  FIGS.  2 A- 2 C . As discussed above, the system is disposed within a physical space/area such as a room, corridor, hallway, or doorway. In one implementation, indoor environment is described, but it is known to one of ordinary skill that the systems and methods described herein are operable in external environments as well. In one implementation, the method  601  is implemented by the processing circuitry  216  of  FIGS.  2 A- 2 C . At block  603 , an indicator data generated at each of the plurality of times from each of the plurality of receivers configured to receive RF spectrum (RF) signals from a RF transmitter in an area is obtained. As discussed above, some of the characteristics include but are not limited to received signal strength indicator (RSSI) data, bit error rate, packet error rate, phase change etc. or a combination of two or more thereof. At block  605 , the indicator data generated at each of the plurality of times from each of the plurality of receivers in the area is processed. In one implementation, the processing includes applying, at each respective one of the plurality of times, a RF signal computation to analyze the indicator data of the RF signals from each of the plurality of receivers. In another implementation, the processing includes applying a heuristic algorithm to the indicator data of the RF signals from each of the plurality of receivers to compute an output metric value for each of a plurality of probable number of occupants in the area. At block  607 , an occupancy count in the area at each of the plurality of times is determined based on the processed indicator data. In one implementation, the determining includes comparing the analyzed indicator data with a pre-determined number of the occupants in the area and determine one of the pre-determined number of occupants to be the occupancy count in the area that best matches with the analyzed indicator data. In another implementation, the determining includes comparing each one of the plurality of occupant values with another one of the plurality of output metric values to determine one of the plurality of computed output metric values as having a largest value among the plurality of computed output metric values; and determining the probable number of occupants associated with the computed output metric value having the largest value as the occupancy count in the area. 
       FIG.  6 B  illustrates an example of a flowchart of a method  600  for heuristically determining an occupancy count for multiple times in area  105  of a system of  FIGS.  2 A- 2 C  or the area  305  of the system of  FIGS.  4 A- 4 C . As discussed above, the system is disposed within a physical space/area such as a room, corridor, hallway, or doorway. In one implementation, indoor environment is described, but it is known to one of ordinary skill that the systems and methods described herein are operable in external environments as well. In one implementation, the method  600  is implemented by the processing circuitry  216  and the learning module  220  of  FIG.  2   . In one implementation, the method  600  is implemented by the processing circuitry  416  and the learning module  420  of  FIG.  4   . 
     At block  602 , an indicator data generated at each of the plurality of times from each of the plurality of receivers configured to receive RF spectrum (RF) signals from one or more RF transmitters in an area is obtained. As discussed above, some of the characteristics include but are not limited to received signal strength indicator (RSSI) data, bit error rate, packet error rate, phase change etc. or a combination of two or more thereof. At block  604 , at each respective one of the plurality of times, a heuristic algorithm coefficient among a set of heuristic algorithm coefficients is applied to each of the indicator data from each of the plurality of receivers for the respective time. In one implementation, during the initial stage of the training, each of the heuristic algorithm coefficients among the set of heuristic algorithm coefficients are randomly selected. At block  606 , at each respective one of the plurality of times, generate an indicator data metric value for each of the indicator data from each of the plurality of receivers for the respective time based on results of the applications of the heuristic algorithm coefficients to the indicator data. At block  608 , at each respective one of the plurality of times, each of the indicator data metric value for each of the indicator data is processed to compute a plurality of metric values (representing a plurality of a probable number of occupants) for the respective receiver for the respective time. In one implementation, each of the plurality of metric values provide a measurement of each of a plurality of a probable number of occupants in the area at the respective time. At block  610 , each of the plurality of metric values is combined to compute an output value for each of the plurality of probable number of occupants in the area at the respective time. At block  612 , each of the plurality of output values are compared with one another to determine an output value among the plurality of output values having a largest value. At block  614 , the probable number of occupants associated with the output value having the largest value is determined to be an occupancy count in the area. 
     At block  616 , at each respective one of the plurality of times, the determined occupancy count is compared with a known occupancy count value. At block  618 , at each of the respective one of the plurality of times, a decision is made whether the determined occupancy count is equivalent to the known occupancy count value. When at block  618 , it is determined that determined occupancy count is equivalent to the known occupancy count value, then at block  620 , it is determined that the set of heuristic algorithm coefficients are optimized heuristic algorithm coefficients. At block  622 , the optimized heuristic algorithm coefficients are utilized to apply to each indicator data for the occupancy count in the area at a real time. When at block  618 , it is determined that the set of heuristic algorithm coefficients are not optimized heuristic algorithm coefficients, then at block  624 , at each of the respective one of the plurality of times, one or more of the set of heuristic algorithm coefficients are updated to generate an updated set of heuristic algorithm coefficients. In one implementation, the method is repeated from block  604  for the updated set of heuristic algorithm coefficients until it is determined that the updated set of heuristic algorithm coefficients are optimized heuristic algorithm coefficients to detect an accurate occupancy count at each respective one of the plurality of times. 
       FIG.  7    is a functional block diagram illustrating an example relating to a system of wireless networked devices that provide a variety of lighting capabilities and may implement RF-based occupancy counting. The wireless networked devices also provide communications in support of lighting functions such as turning lights On/OFF, dimming, set scene, or sensor trip events and may implement RF-based occupancy counting. It should be understood that the term “lighting control device” means a device that includes a controller (Control/XCR module or micro-control unit) that executes a lighting application for communication over a wireless lighting network communication band, of control and systems operations information during control network operation over the lighting network communication band. 
     A lighting system  702  may be designed for indoor commercial spaces, although the system may be used in outdoor or residential settings. As shown, system  702  includes a variety of lighting control devices, such as a set of lighting devices (a.k.a. luminaires)  104   a - 104   n  (lighting fixtures), a set of wall switch type user interface components (a.k.a. wall switches)  720   a - 720   n , a plug load controller type element (a.k.a. plug load controller)  730  and a sensor type element (a.k.a. sensor)  735 . Daylight, ambient light, or audio sensors may embedded in lighting devices, in this case luminaires  704   a - 704   n . RF wireless occupancy counting as described above is implemented in one or more of the luminaires  704   a - 704   n  to enable occupancy/non-occupancy based control of the light sources. One or more luminaires may exist in a wireless network  750 , for example, a sub-GHz or Bluetooth (e.g. 2.4 GHz) network defined by an RF channel and a luminaire identifier. 
     The wireless network  750  may use any available standard technology, such as WiFi, Bluetooth, ZigBee, etc. An example of a lighting system using a wireless network, such as Bluetooth low energy (BLE), is disclosed in patent application publication US 20160248506 A1 entitled “System and Method for Communication with a Mobile Device Via a Positioning System Including RF Communication Devices and Modulated Beacon Light Sources,” the entire contents of which are incorporated herein by reference. Alternatively, the wireless network may use a proprietary protocol and/or operate in an available unregulated frequency band, such as the protocol implemented in nLight® Air products, which transport lighting control messages on the 900 MHz band (an example of which is disclosed in U.S. patent application Ser. No. 15/214,962, filed Jul. 20, 2016, entitled “Protocol for Lighting Control Via a Wireless Network,” the entire contents of which are incorporated herein by reference). The system may support a number of different lighting control protocols, for example, for installations in which consumer selected luminaires of different types are configured for a number different lighting control protocols. 
     The system  702  also includes a gateway  752 , which engages in communication between the lighting system  702  and a server  705  through a network such as wide area network (WAN)  755 . Although  FIG.  7    depicts server  705  as located off premises and accessible via the WAN  755 , any one of the luminaires  704   a - 704   n , for example are configured to communicate occupancy count in an area to devices such as the server  705  or even a laptop  706  located off premises. 
     The lighting control  702  can be deployed in standalone or integrated environments. System  702  can be an integrated deployment, or a deployment of standalone groups with no gateway  752 . One or more groups of lighting system  702  may operate independently of one another with no backhaul connections to other networks. 
     Lighting system  702  can leverage existing sensor and fixture control capabilities of Acuity Brands Lighting&#39;s commercially available nLight® wired product through firmware reuse. In general, Acuity Brands Lighting&#39;s nLight® wired product provides the lighting control applications. However, the illustrated lighting system  704  includes a communications backbone and includes model—transport, network, media access control (MAC)/physical layer (PHY) functions. 
     Lighting control  702  may comprise a mix and match of various indoor systems, wired lighting systems (nLight® wired), emergency, and outdoor (dark to light) products that are networked together to form a collaborative and unified lighting solution. Additional control devices and lighting fixtures, gateway(s)  750  for backhaul connection, time sync control, data collection and management capabilities, and interoperation with the Acuity Brands Lighting&#39;s commercially available SensorView product may also be provided. 
       FIG.  8    is a block diagram of a lighting device (in this example, a luminaire)  804  that operates in and communicates via the lighting system  702  of  FIG.  7   . Luminaire  804  is an integrated light fixture that generally includes a power supply  805  driven by a power source  800 . Power supply  805  receives power from the power source  800 , such as an AC mains, battery, solar panel, or any other AC or DC source. Power supply  805  may include a magnetic transformer, electronic transformer, switching converter, rectifier, or any other similar type of circuit to convert an input power signal into a power signal suitable for luminaire  804 . 
     Luminaire  804  furthers include an intelligent LED driver circuit  810 , control/XCVR module  815 , and a light emitting diode (LED) light source  820 . Intelligent LED driver circuit  810  is coupled to LED light source  820  and drives that LED light source  820  by regulating the power to LED light source  820  by providing a constant quantity or power to LED light source  320  as its electrical properties change with temperature, for example. The intelligent LED driver circuit  810  includes a driver circuit that provides power to LED light source  820  and a pilot LED  817 . The pilot LED  817  may be included as part of the control/XCVR module  315 . Intelligent LED driver circuit  810  may be a constant-voltage driver, constant-current driver, or AC LED driver type circuit that provides dimming through a pulse width modulation circuit and may have many channels for separate control of different LEDs or LED arrays. An example of a commercially available intelligent LED driver circuit  810  is manufactured by EldoLED. 
     LED driver circuit  810  can further include an AC or DC current source or voltage source, a regulator, an amplifier (such as a linear amplifier or switching amplifier), a buck, boost, or buck/boost converter, or any other similar type of circuit or component. LED driver circuit  810  outputs a variable voltage or current to the LED light source  820  that may include a DC offset, such that its average value is nonzero, and/or an AC voltage. 
     Control/XCR module  815  includes power distribution circuitry  825  and a micro-control unit (MCU)  830 . As shown, MCU  830  is coupled to LED driver circuit  810  and controls the light source operation of the LED light source  820 . MCU  830  includes a memory  322  (volatile and non-volatile) and a central processing unit (CPU)  823 . The memory  822  includes a lighting application  827  (which can be firmware) for both occupancy counting and lighting control operations. The power distribution circuitry  825  distributes power and ground voltages to the MCU  830 , wireless transmitter  808  and wireless receiver  810 , to provide reliable operation of the various circuitry on the sensor/processing circuitry  815  chip. 
     Luminaire  804  also includes a wireless radio communication interface system configured for two way wireless communication on at least one band. Optionally, the wireless radio communication interface system may be a dual-band system. It should be understood that “dual-band” means communications over two separate RF bands. The communication over the two separate RF bands can occur simultaneously (concurrently); however, it should be understood that the communication over the two separate RF bands may not actually occur simultaneously. 
     In our example, luminaire  804  has a radio set that includes radio transmitter  808  as well as a radio receiver  810 , together forming a radio transceiver. The wireless transmitter  808  transmits RF signals on the lighting network. This wireless transmitter  808  wireless communication of control and systems operations information, during luminaire operation and during transmission over the first wireless communication band. The wireless receiver carries out receiving of the RF signals from other system elements on the network and generating RSSI data based on signal strengths of the received RF signals. If provided (optional) another transceiver (Tx and Rx) may be provided, for example, for point-to-point communication, over a second different wireless communication bands, e.g. for communication of information other than the control and systems operations information, concurrently with at least some communications over the first wireless communication band. Optionally, the luminaire  804  may have a radio set forming a second transceiver (shown in dotted lines, transmitter and receiver not separately shown). 
     The included transceiver (solid lines), for example, may be a sub GHz transceiver or a Bluetooth transceiver configured to operate in a standard GHz band. A dual-band implementation might include two transceivers for different bands, e.g. for a sub GHz band and a GHz band for Bluetooth or the like. Additional transceivers may be provided. The particular bands/transceivers are described here by way of non-limiting example, only. 
     If two bands are supported, the two bands may be for different applications, e.g. lighting system operational communications and system element maintenance/commissioning. Alternatively, the two bands may support traffic segregation, e.g. one band may be allocated to communications of the entity owning/operating the system at the premises whereas the other band may be allocated to communications of a different entity such as the system manufacturer or a maintenance service bureau. 
     The RF spectrum or “radio spectrum” is a non-visible part of the electromagnetic spectrum, for example, from around 3 MHz up to approximately 3 THz, which may be used for a variety of communication applications, radar applications, or the like. In the discussions above, the RF transmitted and received for network communication, e.g. Wifi, BLE, Zigbee etc., was also used for occupancy counting functions, in the frequencies bands/bandwidths specified for those standard wireless RF spectrum data communication technologies. In another implementation, the transceiver is an ultra-wide band (also known as UWB, ultra-wide band and ultra band) transceiver. UWB is a radio technology that can use a very low energy level for short-range, high-bandwidth communications over a large portion of the radio spectrum. UWB does not interfere with conventional narrowband and carrier wave transmission in the same frequency band. Ultra-wideband is a technology for transmitting information spread over a large bandwidth (&gt;500 MHz) and under certain circumstances be able to share spectrum with other users. 
     Ultra-wideband characteristics are well-suited to short-distance applications, such as short-range indoor applications. High-data-rate UWB may enable wireless monitors, the efficient transfer of data from digital camcorders, wireless printing of digital pictures from a camera without the need for a personal computer and file transfers between cell-phone handsets and handheld devices such as portable media players. UWB may be used in a radar configuration (emitter and deflection detection at one node) for real-time location systems and occupancy sensing/counting systems; its precision capabilities and low power make it well-suited for radio-frequency-sensitive environments. Another feature of UWB is its short broadcast time. Ultra-wideband is also used in “see-through-the-wall” precision radar-imaging technology, precision detecting and counting occupants (between two radios), precision locating and tracking (using distance measurements between radios), and precision time-of-arrival-based localization approaches. It is efficient, with a spatial capacity of approximately 1013 bit/s/m 2 . In one example, the UWB is used as the active sensor component in an automatic target recognition application, designed to detect humans or objects in any environment. 
     The MCU  830  may be a system on a chip. Alternatively, a system on a chip may include the transmitter  808  and receiver  810  as well as the circuitry of the MCU  830 . 
     As shown, the MCU  830  includes programming in the memory  822 . A portion of the programming configures the CPU (processor)  823  to determine occupancy counting in an area in the lighting network, including the communications over one or more wireless communication. The programming in the memory  822  includes a real-time operating system (RTOS) and further includes a lighting application  827  which is firmware/software that engages in communications with controlling of the light source based on occupancy counting determined by the CPU  823 . The lighting application  827  programming in the memory  822  carries out lighting control operations over the lighting network  750  of  FIG.  7   . The programming for the determination of an occupancy count in the area may be implemented as part of the RTOS, as part of the lighting application  827 , as a standalone application program, or as other instructions in the memory. 
       FIG.  9    is a block diagram of a wall type user interface element  915  that operates in and communicates via the lighting system  702  of  FIG.  7   . Wall type user interface (UI) element (UI element) is an integrated wall switch that generally includes a power supply  905  driven by a power source  900 . Power supply  905  receives power from the power source  900 , such as an AC mains, battery, solar panel, or any other AC or DC source. Power supply  905  may include a magnetic transformer, electronic transformer, switching converter, rectifier, or any other similar type of circuit to convert an input power signal into a power signal suitable for the UI element  915 . 
     UI element  915  furthers includes an intelligent LED driver circuit  910 , coupled to LED (s)  920  and drives that LED light source (LED)  920  by regulating the power to LED  820  by providing a constant quantity or power to LED  920  as its electrical properties change with temperature, for example. The intelligent LED driver circuit  910  includes a driver circuit that provides power to LED  920  and a pilot LED  917 . Intelligent LED driver circuit  910  may be a constant-voltage driver, constant-current driver, or AC LED driver type circuit that provides dimming through a pulse width modulation circuit and may have many channels for separate control of different LEDs or LED arrays. An example of a commercially available intelligent LED driver circuit  910  is manufactured by EldoLED. 
     LED driver circuit  910  can further include an AC or DC current source or voltage source, a regulator, an amplifier (such as a linear amplifier or switching amplifier), a buck, boost, or buck/boost converter, or any other similar type of circuit or component. LED driver circuit  910  outputs a variable voltage or current to the LED light source  920  that may include a DC offset, such that its average value is nonzero, and/or an AC voltage. 
     The UI element  915  includes power distribution circuitry  925  and a micro-control unit (MCU)  930 . As shown, MCU  930  is coupled to LED driver circuit  910  and controls the light source operation of the LED  920 . MCU  930  includes a memory  922  (volatile and non-volatile) and a central processing unit (CPU)  923 . The memory  922  includes a lighting application  927  (which can be firmware) for both occupancy counting and lighting control operations. The power distribution circuitry  925  distributes power and ground voltages to the MCU  930 , wireless transmitter  908  and wireless receiver  910 , to provide reliable operation of the various circuitry on the UI element  915  chip. 
     The UI element  915  also includes a wireless radio communication interface system configured for two way wireless communication on at least one band. Optionally, the wireless radio communication interface system may be a dual-band system. It should be understood that “dual-band” means communications over two separate RF bands. The communication over the two separate RF bands can occur simultaneously (concurrently); however, it should be understood that the communication over the two separate RF bands may not actually occur simultaneously. 
     In our example, the UI element  915  has a radio set that includes radio transmitter  908  as well as a radio receiver  910  together forming a radio transceiver. The wireless transmitter  908  transmits RF signals on the lighting network. This wireless transmitter  908  wireless communication of control and systems operations information, during luminaire operation and during transmission over the first wireless communication band. The wireless receiver carries out receiving of the RF signals from other system elements on the network and generating RSSI data based on signal strengths of the received RF signals. If provided (optional) another transceiver (Tx and Rx) may be provided, for example, for point-to-point communication, over a second different wireless communication bands, e.g. for communication of information other than the control and systems operations information, concurrently with at least some communications over the first wireless communication band. Optionally, the UI element  915  may have a radio set forming a second transceiver (shown in dotted lines, transmitter and receiver not separately shown). 
     The included transceiver (solid lines), for example, may be a sub GHz transceiver or a Bluetooth transceiver configured to operate in a standard GHz band. A dual-band implementation might include two transceivers for different bands, e.g. for a sub GHz band and a GHz band for Bluetooth or the like. Additional transceivers may be provided. The particular bands/transceivers are described here by way of non-limiting example, only. 
     If two bands are supported, the two bands may be for different applications, e.g. lighting system operational communications and system element maintenance/commissioning. Alternatively, the two bands may support traffic segregation, e.g. one band may be allocated to communications of the entity owning/operating the system at the premises whereas the other band may be allocated to communications of a different entity such as the system manufacturer or a maintenance service bureau. 
     The MCU  930  may be a system on a chip. Alternatively, a system on a chip may include the transmitter  908  and receiver  910  as well as the circuitry of the MCU  930 . 
     As shown, the UI element  915  includes a drive/sense circuitry  935 , such as an application firmware, drives the occupancy, audio, and photo sensor hardware. The drive/sense circuitry  935  detects state changes (such as change of occupancy, audio or daylight sensor or switch to turn lighting on/off, dim up/down or set scene) via switches  965 , such as a dimmer switch, set scene switch. Switches  965  can be or include sensors, such as infrared sensors for occupancy or motion detection, occupancy count, an in-fixture daylight sensor, an audio sensor, a temperature sensor, or other environmental sensor. Switches  965  may be based on Acuity Brands Lighting&#39;s commercially available xPoint® Wireless ES7 product. 
     Also, as shown, the MCU  930  includes programming in the memory  922 . A portion of the programming configures the CPU (processor)  923  to determine occupancy count in an area in the lighting network, including the communications over one or more wireless communication bands. The programming in the memory  922  includes a real-time operating system (RTOS) and further includes a lighting application  927  which is firmware/software that engages in communications with controlling of the light source based on one of the occupancy count determined by the CPU  923 . As shown, a drive/sense circuitry detects a state change event. The lighting application  927  programming in the memory  922  carries out lighting control operations over the lighting system  702  of  FIG.  7   . The programming for the determination of an occupancy count in the area may be implemented as part of the RTOS, as part of the lighting application  927 , as a standalone application program, or as other instructions in the memory. 
       FIG.  10    is a block diagram of a sensor type element,  1015  that operates in and communicates via the lighting system  702  of  FIG.  7   . Sensor type element is an integrated sensor detector that generally includes a power supply  1005  driven by a power source  1000 . Power supply  805  receives power from the power source  1000 , such as an AC mains, battery, solar panel, or any other AC or DC source. Power supply  1005  may include a magnetic transformer, electronic transformer, switching converter, rectifier, or any other similar type of circuit to convert an input power signal into a power signal suitable for the sensor type element  1015 . 
     The sensor type element  1015  includes power distribution circuitry  1025  and a micro-control unit (MCU)  1030 . As shown, MCU  1030  includes a memory  1022  (volatile and non-volatile) and a central processing unit (CPU)  1023 . The memory  1022  includes a lighting application  1027  (which can be firmware) for both occupancy counting and lighting control operations. The power distribution circuitry  1925  distributes power and ground voltages to the MCU  1030 , wireless transmitter  1008  and wireless receiver  1010 , to provide reliable operation of the various circuitry on the sensor type element  1015  chip. 
     The sensor type element  1015  also includes a wireless radio communication interface system configured for two way wireless communication on at least one band. Optionally, the wireless radio communication interface system may be a dual-band system. It should be understood that “dual-band” means communications over two separate RF bands. The communication over the two separate RF bands can occur simultaneously (concurrently); however, it should be understood that the communication over the two separate RF bands may not actually occur simultaneously. 
     In our example, the sensor type element  1015  has a radio transmitter  1008  as well as radio receiver  1010  together forming a radio transceiver. The wireless transmitter  1008  transmits RF signals on the lighting network. This wireless transmitter  1008  wireless communication of control and systems operations information, during luminaire operation and during transmission over the first wireless communication band. The wireless receiver carries out receiving of the RF signals from other system elements on the network and generating RSSI data based on signal strengths of the received RF signals. If provided (optional) another transceiver (Tx and Rx) may be provided, for example, for point-to-point communication, over a second different wireless communication bands, e.g. for communication of information other than the control and systems operations information, concurrently with at least some communications over the first wireless communication band. Optionally, the luminaire sensor type element  1015  may have a radio set forming a second transceiver (shown in dotted lines, transmitter and receiver not separately shown). 
     The included transceiver (solid lines), for example, may be a sub GHz transceiver or a Bluetooth transceiver configured to operate in a standard GHz band. A dual-band implementation might include two transceivers for different bands, e.g. for a sub GHz band and a GHz band for Bluetooth or the like. Additional transceivers may be provided. The particular bands/transceivers are described here by way of non-limiting example, only. 
     If two bands are supported, the two bands may be for different applications, e.g. lighting system operational communications and system element maintenance/commissioning. Alternatively, the two bands may support traffic segregation, e.g. one band may be allocated to communications of the entity owning/operating the system at the premises whereas the other band may be allocated to communications of a different entity such as the system manufacturer or a maintenance service bureau. 
     The MCU  1030  may be a system on a chip. Alternatively, a system on a chip may include the transmitter  1008  and the receiver  1010  as well as the circuitry of the MCU  830 . 
     As shown, the sensor type element  1015  includes a drive/sense circuitry  1035 , such as an application firmware, drives the occupancy, daylight, audio, and photo sensor hardware. The drive/sense circuitry  1035  detects state changes (such as change of occupancy, audio or daylight) via sensor detector(s)  1065 , such as occupancy count, audio, daylight, temperature or other environment related sensors. Sensors  1065  may be based on Acuity Brands Lighting&#39;s commercially available xPoint® Wireless ES7 product. 
     Also as shown, the MCU  1030  includes programming in the memory  1022 . A portion of the programming configures the CPU (processor)  1023  to determine occupancy count in an area in the lighting network, including the communications over one or more different wireless communication bands. The programming in the memory  1022  includes a real-time operating system (RTOS) and further includes a lighting application  1027  which is firmware/software that engages in communications with controlling of the light source based on occupancy count determined by the CPU  1023 . The lighting application  1027  programming in the memory  1022  carries out lighting control operations over the lighting system  702  of  FIG.  7   . The programming for the determination of an occupancy count in the area may be implemented as part of the RTOS, as part of the lighting application  1027 , as a standalone application program, or as other instructions in the memory. 
       FIG.  11    is a block diagram of a plug load controller type element (plug load element)  1115  that operates in and communicates via the lighting system  702  of  FIG.  7   . In one example, plug load element  1115  is an integrated switchable power connector that generally includes a power supply  1105  driven by a power source  1100 . Power supply  1105  receives power from the power source  1100 , such as an AC mains, battery, solar panel, or any other AC or DC source. Power supply  1105  may include a magnetic transformer, electronic transformer, switching converter, rectifier, or any other similar type of circuit to convert an input power signal into a power signal suitable for the plug load element  1115 . 
     Plug load element  1115  includes an intelligent LED driver circuit  1110 , coupled to LED (s)  1120  and drives that LED light source (LED) by regulating the power to LED  1120  by providing a constant quantity or power to LED  1120  as its electrical properties change with temperature, for example. The intelligent LED driver circuit  1110  includes a driver circuit that provides power to LED  1120  and a pilot LED  1117 . Intelligent LED driver circuit  1110  may be a constant-voltage driver, constant-current driver, or AC LED driver type circuit that provides dimming through a pulse width modulation circuit and may have many channels for separate control of different LEDs or LED arrays. An example of a commercially available intelligent LED driver circuit  1110  is manufactured by EldoLED. 
     LED driver circuit  1110  can further include an AC or DC current source or voltage source, a regulator, an amplifier (such as a linear amplifier or switching amplifier), a buck, boost, or buck/boost converter, or any other similar type of circuit or component. LED driver circuit  1110  outputs a variable voltage or current to the LED light source  1120  that may include a DC offset, such that its average value is nonzero, and/or an AC voltage. 
     The plug load element  1115  includes power distribution circuitry  1125  and a micro-control unit (MCU)  1130 . As shown, MCU  1130  is coupled to LED driver circuit  1110  and controls the light source operation of the LED  1120 . MCU  1130  includes a memory  1122  (volatile and non-volatile) and a central processing unit (CPU)  1123 . The memory  1122  includes a lighting application  1127  (which can be firmware) for both occupancy counting and lighting control operations. The power distribution circuitry  1125  distributes power and ground voltages to the MCU  1130 , wireless transmitter  1108  and wireless receiver  1110 , to provide reliable operation of the various circuitry on the plug load control  1115  chip. 
     The plug load element  1115  also includes a wireless radio communication interface system configured for two way wireless communication on at least one band. Optionally, the wireless radio communication interface system may be a dual-band system. It should be understood that “dual-band” means communications over two separate RF bands. The communication over the two separate RF bands can occur simultaneously (concurrently); however, it should be understood that the communication over the two separate RF bands may not actually occur simultaneously. 
     In our example, the plug load element  1115  has a radio set that includes radio transmitter  1108  as well as a radio receiver  1110  forming a radio transceiver. The wireless transmitter  1108  transmits RF signals on the lighting network. This wireless transmitter  1108  wireless communication of control and systems operations information, during luminaire operation and during transmission over the first wireless communication band. The wireless receiver carries out receiving of the RF signals from other system elements on the network and generating RSSI data based on signal strengths of the received RF signals. If provided (optional) another transceiver (Tx and Rx) may be provided, for example, for point-to-point communication, over a second different wireless communication bands, e.g. for communication of information other than the control and systems operations information, concurrently with at least some communications over the first wireless communication band. Optionally, the plug load element  1115  may have a radio set forming a second transceiver (shown in dotted lines, transmitter and receiver not separately shown). 
     The included transceiver (solid lines), for example, may be a sub GHz transceiver or a Bluetooth transceiver configured to operate in a standard GHz band. A dual-band implementation might include two transceivers for different bands, e.g. for a sub GHz band and a GHz band for Bluetooth or the like. Additional transceivers may be provided. The particular bands/transceivers are described here by way of non-limiting example, only. 
     If two bands are supported, the two bands may be for different applications, e.g. lighting system operational communications and system element maintenance/commissioning. Alternatively, the two bands may support traffic segregation, e.g. one band may be allocated to communications of the entity owning/operating the system at the premises whereas the other band may be allocated to communications of a different entity such as the system manufacturer or a maintenance service bureau. 
     The MCU  1130  may be a system on a chip. Alternatively, a system on a chip may include the transmitter  1108  and the receiver  1110  as well as the circuitry of the MCU  1130 . 
     Plug load element  1115  plugs into existing AC wall outlets, for example, and allows existing wired lighting devices, such as table lamps or floor lamps that plug into a wall outlet, to operate in the lighting system. The plug load element  1115  instantiates the table lamp or floor lamp by allowing for commissioning and maintenance operations and processes wireless lighting controls in order to the allow the lighting device to operate in the lighting system. Plug load element  1115  further comprises an AC power relay  1160  which relays incoming AC power from power source  1100  to other devices that may plug into the receptacle of plug load element  1115  thus providing an AC power outlet  1170 . 
     Also, as shown, the MCU  1130  includes programming in the memory  1122 . A portion of the programming configures the CPU (processor)  1123  to determine occupancy count in an area in the lighting network, including the communications over one or more wireless communication bands. The programming in the memory  1122  includes a real-time operating system (RTOS) and further includes a lighting application  1127  which is firmware/software that engages in communications with controlling of the light source based on the occupancy count determined by the CPU  1123 . As shown, a drive/sense circuitry detects a state change event. The lighting application  1127  programming in the memory  1122  carries out lighting control operations over the lighting system  702  of  FIG.  7   . The programming for the determination of the occupancy count in the area may be implemented as part of the RTOS, as part of the lighting application  1127 , as a standalone application program, or as other instructions in the memory. 
       FIGS.  12  and  13    provide functional block diagram illustrations of general purpose computer hardware platforms that may be configured to implement some or all of the processor or controller functions in the examples described above with respect to  FIGS.  1 - 6   . The computer hardware platforms may also be used to implement server  705 , the terminal computer  706  or the gateway  752  of  FIG.  7   . 
     Specifically,  FIG.  12    illustrates a network or host computer platform, as may typically be used to implement a server. Specifically,  FIG.  13    depicts a computer with user interface elements, as may be used to implement a personal computer or other type of work station or terminal device, although the computer of  FIG.  13    may also act as a server if appropriately programmed. It is believed that those skilled in the art are familiar with the structure, programming and general operation of such computer equipment and as a result the drawings should be self-explanatory. 
     Hardware of a server computer, for example ( FIG.  12   ), includes a data communication interface for packet data communication. The server computer also includes a central processing unit (CPU), in the form of circuitry forming one or more processors, for executing program instructions. The server platform hardware typically includes an internal communication bus, program and/or data storage for various programs and data files to be processed and/or communicated by the server computer, although the server computer often receives programming and data via network communications. The hardware elements, operating systems and programming languages of such server computers are conventional in nature, and it is presumed that those skilled in the art are adequately familiar therewith. Of course, the server functions may be implemented in a distributed fashion on a number of similar hardware platforms, to distribute the processing load. 
     Hardware of a computer type user terminal device, such as a PC or tablet computer, similarly includes a data communication interface, CPU, main memory and one or more mass storage devices for storing user data and the various executable programs (see  FIG.  13   ). 
     Aspects of the methods for occupancy counting in a nodal network, as outlined above, may be embodied in programming in (such as described above  FIGS.  12  and  13   ), e.g. in the form of software, firmware, or microcode executable by a networked computer system such as a server or gateway, and/or a programmable nodal device. Program aspects of the technology may be thought of as “products” or “articles of manufacture” typically in the form of executable code and/or associated data that is carried on or embodied in a type of machine readable medium. “Storage” type media include any or all of the tangible memory of the computers, processors or the like, or associated modules thereof, such as various semiconductor memories, tape drives, disk drives and the like, which may provide non-transitory storage at any time for the software programming. All or portions of the software may at times be communicated through the Internet or various other telecommunication networks. Such communications, for example, may enable loading of the software, from one computer or processor into another, for example, from a management server or host processor (e.g. from server  705 , terminal computer  706  or gateway  752  of  FIG.  7   ) into the processing circuitry  216  of the systems  200 ,  201  and  202  of  FIGS.  2 A,  2 B and  2 C  respectively or the processing circuitry  416  of the systems  400 ,  401  and  402  of  FIGS.  4 A,  4 B and  4 C  respectively. Thus, another type of media that may bear the software elements includes optical, electrical and electromagnetic waves, such as used across physical interfaces between local devices, through wired and optical landline networks and over various air-links. The physical elements that carry such waves, such as wired or wireless links, optical links or the like, also may be considered as media bearing the software. As used herein, unless restricted to one or more of “non-transitory,” “tangible” or “storage” media, terms such as computer or machine “readable medium” refer to any medium that participates in providing instructions to a processor for execution. 
     Hence, a machine readable medium may take many forms, including but not limited to, a tangible storage medium, a carrier wave medium or physical transmission medium. Non-transitory storage media include, for example, optical or magnetic disks, such as any of the storage devices in any computer(s) or the like. It may also include storage media such as dynamic memory, for example, the main memory of a machine or computer platform. Tangible transmission media include coaxial cables; copper wire and fiber optics, including the wires that include a bus within a computer system. Carrier-wave transmission media can take the form of electric or electromagnetic signals, or acoustic or light waves such as those generated during radio frequency (RF) and light-based data communications. Common forms of computer-readable media therefore include for example: a floppy disk, a flexible disk, hard disk, magnetic tape, any other magnetic medium, a CD-ROM, DVD or DVD-ROM, any other optical medium, punch cards paper tape, any other physical storage medium with patterns of holes, a RAM, a PROM and EPROM, a FLASH-EPROM, any other memory chip or cartridge, a carrier wave transporting data or instructions, cables or links transporting such a carrier wave, or any other medium from which a computer can read programming code and/or data. Many of these forms of computer readable media may be involved in carrying one or more sequences of one or more instructions to a processor for execution. 
     Program instructions may include a software or firmware implementation encoded in any desired language. Programming instructions, when embodied in machine readable medium accessible to a processor of a computer system or device, render computer system or device into a special-purpose machine that is customized to perform the operations specified in the program performed by the systems  200 ,  201  and  202  of  FIGS.  2 A,  2 B and  2 C  respectively or the processing circuitry  416  of the systems  400 ,  401  and  402  of  FIGS.  4 A,  4 B and  4 C  respectively. 
     While the foregoing has described what are considered to be the best mode and/or other examples, it is understood that various modifications may be made therein and that the subject matter disclosed herein may be implemented in various forms and examples, and that the teachings may be applied in numerous applications, only some of which have been described herein. It is intended by the following claims to claim any and all applications, modifications and variations that fall within the true scope of the present teachings. 
     Unless otherwise stated, all measurements, values, ratings, positions, magnitudes, sizes, and other specifications that are set forth in this specification, including in the claims that follow, are approximate, not exact. They are intended to have a reasonable range that is consistent with the functions to which they relate and with what is ordinary in the art to which they pertain. 
     The scope of protection is limited solely by the claims that now follow. That scope is intended and should be interpreted to be as broad as is consistent with the ordinary meaning of the language that is used in the claims when interpreted in light of this specification and the prosecution history that follows and to encompass all structural and functional equivalents. Notwithstanding, none of the claims are intended to embrace subject matter that fails to satisfy the requirement of Sections 101, 102, or 103 of the Patent Act, nor should they be interpreted in such a way. Any unintended embracement of such subject matter is hereby disclaimed. 
     Except as stated immediately above, nothing that has been stated or illustrated is intended or should be interpreted to cause a dedication of any component, step, feature, object, benefit, advantage, or equivalent to the public, regardless of whether it is or is not recited in the claims. 
     It will be understood that the terms and expressions used herein have the ordinary meaning as is accorded to such terms and expressions with respect to their corresponding respective areas of inquiry and study except where specific meanings have otherwise been set forth herein. Relational terms such as first and second and the like may be used solely to distinguish one entity or action from another without necessarily requiring or implying any actual such relationship or order between such entities or actions. The terms “comprises,” “comprising,” “includes,” “including,” or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. An element preceded by “a” or “an” does not, without further constraints, preclude the existence of additional identical elements in the process, method, article, or apparatus that includes the element. 
     The term “coupled” as used herein refers to any logical, physical or electrical connection, link or the like by which signals produced by one system element are imparted to another “coupled” element. Unless described otherwise, coupled elements or devices are not necessarily directly connected to one another and may be separated by intermediate components, elements or communication media that may modify, manipulate or carry the signals. Each of the various couplings may be considered a separate communications channel. 
     The Abstract of the Disclosure is provided to allow the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. In addition, in the foregoing Detailed Description, it can be seen that various features are grouped together in various examples for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the claimed examples require more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive subject matter lies in less than all features of a single disclosed example. Thus the following claims are hereby incorporated into the Detailed Description, with each claim standing on its own as a separately claimed subject matter.