Patent Description:
Embodiments pertain to wireless communications. Some embodiments relate to time-of-flight positioning and device location wireless networks. Some embodiments relate to wireless networks that operate in accordance with one of the IEEE <NUM> standards. Some embodiments relate to the use of wireless geo-location, more specifically, some embodiments relate to determining a location of a device within a space equipped with a wireless network.

Accurately locating wireless network devices may incur a computational cost associated with performing numerous location determinations from multiple terrestrial sources. This computational cost may impact other processing activities of a device and also incur additional power consumption, which may degrade the performance or usability of the device. Thus there are general needs for systems and methods that reduce the costs associated with accurately locating a wireless device. CARLOS ALDANA (QUALCOMM), "<NUM>-<NUM> CID_46_47_48 ; <NUM>-<NUM>-<NUM>-<NUM>-<NUM>-<NUM>-<NUM>-<NUM>-cid-<NUM>-<NUM>-<NUM>", IEEE SA MENTOR; <NUM>-<NUM>-<NUM>-<NUM>-<NUM>-<NUM>-<NUM>-<NUM>-CID-<NUM>-<NUM>-<NUM>, IEEE-SA MENTOR, PISCATAWAY, NJ <CIT>), vol. <NUM>, pages <NUM>-<NUM> discloses the resolution of CIDs <NUM>, <NUM><NUM> regarding fine timing measurement.

Some embodiments are illustrated by way of example and not limitation in the figures of the accompanying drawings in which:.

Various techniques and configurations described herein provide for a location discovery technique used in conjunction with wireless communications and network communications. The presently described location techniques may be used in conjunction with wireless communication between devices and access points. For example, a wireless local area network (e.g., Wi-Fi) may be based on, or compatible with, one of the Institute of Electrical and Electronics Engineers (IEEE) <NUM> standards.

With some network technologies, establishing the location of a device makes use of time of flight (TOF) calculations to calculate the distances between the device and multiple access points. For example, a device may request TOF information from two or more access points in order to establish a physical distance from each individual access point, and thereby determining an approximate physical location of the device with respect to the access points. In an example where the physical location of the access points is known, the access points may provide the device with that location information such that the device, alone or in conjunction with the access points, may determine a precise physical location of the device, for example, as a set of latitude and longitude values in a navigational coordinate system.

In connection with the presently described techniques, a wireless communications device is utilized to establish a connection with a wireless communications access point. In an example, an IEEE <NUM> standard, such as IEEE <NUM>. 11v, may define a frame exchange from which time of flight (ToF) can be determined, but assume the availability of a mobile device to receive the response at all times. However, ToF calculations may take few milliseconds, forcing the mobile device to dwell on the requested channel until a response arrives, thereby preventing the device from returning to the serving channel (if the serving channel is not equal to the current ToF exchange channel). This prevents the device from performing any power saving techniques, or performing an additional exchange with an AP on different channel. Additionally, ToF calculation resources may not be available at all times due to a prior interaction between the device and a recipient APto prepare one side (or both) for the upcoming ToF measurement exchange.

In order to facilitate trilateration required for location accuracy, a device may perform a ToF exchange with several APs. For example, in an enterprise environment were access points frequency spread across the spectrum, additional time for the mobile device to dwell and/or out of channel may be needed and may be multiplied by the number of relevant ToF supporting APs set to different channels.

In some embodiments, a method for time-of-flight (ToF) positioning may include a three-stage fine-timing measurement (FTM) procedure performed by an initiating station and a responding station. The method may comprise a first stage (stage I) for negotiating comeback timing for a next FTM exchange; a second stage (stage II) that includes performing a fine-timing measurement exchange, and optionally negotiating the comeback timing for a next fine-timing measurement exchange; and a third stage (stage III) that includes reporting and polling the timestamp of the previous fine timing measurement exchange, and optionally performing an additional fine-timing measurement stage.

These location techniques may provide a ToF responder, for example an access point, with the capability to manage and prepare required ToF resources. They may also provide a ToF Initiator (e.g., a STA or device) a capability to perform parallel operations while waiting for responder resources, such operations may include: power save, performance of additional ToF requests with another responder, handling of serving channel traffic, or other functions. Additionally, the ToF infrastructure protocols described herein provide for additional extensions to location protocols, such as full availability of ToF resources at all times, fast channel estimation calculation, along with robust and well defined error handling mechanisms.

These location techniques may facilitate the determination of a device location using any of a variety of network protocols and standards in licensed or unlicensed spectrum bands, including Wi-Fi communications performed in connection with an IEEE <NUM> standard (for example, Wi-Fi communications facilitated by fixed access points), 3GPP LTE/LTE-A communications (for example, LTE Direct (LTE-D) communications established in a portion of an uplink segment or other designated resources), machine-to-machine (M2M) communications performed in connection with an IEEE <NUM> standard, and the like.

<FIG> provides an illustration of an example configuration of a communication network architecture <NUM>. Within the communication network architecture <NUM>, a carrier-based network such as an IEEE <NUM> compatible wireless access point or a LTE/LTE-A cell network operating according to a standard from a 3GPP standards family is established by network equipment <NUM>. The network equipment <NUM> may include a wireless access point, a Wi-Fi hotspot, or an enhanced or evolved node B (eNodeB) communicating with communication devices 104A, 104B, 104C (e.g., a user equipment (UE) or a communication station (STA)). The carrier-based network includes wireless network connections 106A, 106B, and 106C with the communication devices 104A, 104B, and 104C, respectively. The communication devices 104A, 104B, 104C are illustrated as conforming to a variety of form factors, including a smartphone, a mobile phone handset, and a personal computer having an integrated or external wireless network communication device.

The network equipment <NUM> is illustrated in <FIG> as being connected via a network connection <NUM> to network servers <NUM> in a cloud network <NUM>. The servers <NUM> may operate to provide various types of information to, or receive information from, communication devices 104A, 104B, 104C, including device location, user profiles, user information, web sites, e-mail, and the like. The techniques described herein enable the determination of the location of the various communication devices 104A, 104B, 104C, with respect to the network equipment <NUM> without requiring the various communication devices to establish a communication session with more than one network equipment.

Communication devices 104A, 104B, 104C may communicate with the network equipment <NUM> when in range or otherwise in proximity for wireless communications. As illustrated, the connection 106A may be established between the mobile device 104A (e.g., a smartphone) and the network equipment <NUM>; the connection 106B may be established between the mobile device 104B (e.g., a mobile phone) and the network equipment <NUM>; and the connection 106C may be established between the mobile device 104C (e.g., a personal computer) and the network equipment <NUM>.

The wireless communications 106A, 106B, 106C between devices 104A, 104B, 104C may utilize a Wi-Fi or IEEE <NUM> standard protocol, or a protocol such as the current 3rd Generation Partnership Project (3GPP) long term evolution (LTE) time division duplex (TDD)-Advanced systems. In one embodiment, the communications network <NUM> and network equipment <NUM> comprises an evolved universal terrestrial radio access network (EUTRAN) using the 3rd Generation Partnership Project (3GPP) long term evolution (LTE) standard and operating in time division duplexing (TDD) mode. The devices 104A, 104B, 104C may include one or more antennas, receivers, transmitters, or transceivers that are configured to utilize a Wi-Fi or IEEE <NUM> standard protocol, or a protocol such as 3GPP, LTE, or TDD-Advanced or any combination of these or other communications standards.

Antennas in or on devices 104A, 104B, 104C may comprise one or more directional or omnidirectional antennas, including, for example, dipole antennas, monopole antennas, patch antennas, loop antennas, microstrip antennas or other types of antennas suitable for transmission of RF signals. In some embodiments, instead of two or more antennas, a single antenna with multiple apertures may be used. In these embodiments, each aperture may be considered a separate antenna. In some multiple-input multiple-output (MIMO) embodiments, antennas may be effectively separated to utilize spatial diversity and the different channel characteristics that may result between each of the antennas and the antennas of a transmitting station. In some MIMO embodiments, antennas may be separated by up to <NUM>/<NUM> of a wavelength or more.

In some embodiments, the mobile device 104A may include one or more of a keyboard, a display, a non-volatile memory port, multiple antennas, a graphics processor, an application processor, speakers, and other mobile device elements. The display may be an LCD screen including a touch screen. The mobile device 104B may be similar to mobile device 104A, but does not need to be identical. The mobile device 104C may include some or all of the features, components, or functionality described with respect to mobile device 104A.

A base station, such as an enhanced or evolved node B (eNodeB), may provide wireless communication services to communication devices, such as device 104A. While the exemplary communication system <NUM> of <FIG> depicts only three devices users 104A, 104B, 104C any combination of multiple users, devices, servers and the like may be coupled to network equipment <NUM> in various embodiments. For example, three or more users located in a venue, such as a building, campus, mall area, or other area, and may utilize any number of mobile wireless-enabled computing devices to independently communicate with network equipment <NUM>. Similarly, communication system <NUM> may include more than one network equipment <NUM>. For example, a plurality of access points or base stations may form an overlapping coverage area where devices may communicate with at least two instances of network equipment <NUM>.

Although communication system <NUM> is illustrated as having several separate functional elements, one or more of the functional elements may be combined and may be implemented by combinations of software-configured elements, such as processing elements including digital signal processors (DSPs), and/or other hardware elements. For example, some elements may comprise one or more microprocessors, DSPs, application specific integrated circuits (ASICs), radio-frequency integrated circuits (RFICs) and combinations of various hardware and logic circuitry for performing at least the functions described herein. In some embodiments, the functional elements of system <NUM> may refer to one or more processes operating on one or more processing elements.

Embodiments may be implemented in one or a combination of hardware, firmware and software. Embodiments may also be implemented as instructions stored on a computer-readable storage device, which may be read and executed by at least one processor to perform the operations described herein. A computer-readable storage device may include any non-transitory mechanism for storing information in a form readable by a machine (e.g., a computer). For example, a computer-readable storage device may include read-only memory (ROM), random-access memory (RAM), magnetic disk storage media, optical storage media, flash-memory devices, and other storage devices and media. In some embodiments, system <NUM> may include one or more processors and may be configured with instructions stored on a computer-readable storage device.

<FIG> is a block diagram of an example wireless communication system <NUM> that may utilize the communication network architecture <NUM> of <FIG>. The exemplary communication system <NUM> may include a device <NUM> that is capable of wireless communication (e.g., a user equipment (UE) or communication station (STA)). The communication system <NUM> may include a device <NUM> that is capable of wireless communication. The device <NUM> may include a receiver <NUM> (e.g., as part of a transceiver) and a processor <NUM>. The processor <NUM> may be any hardware, or subset of hardware, that can perform the specified operation. An enumeration of such hardware elements is given below with respect to <FIG>, <FIG> or <FIG>.

The processor <NUM> may be arranged to communicate with a position calculator <NUM>. In an example, the position calculator <NUM> is local to (e.g., a part of, integrated with, belonging to, etc.) the device <NUM>. In an example, the position calculator <NUM> is remote from (e.g., distant, accessible indirectly via a network (e.g., <NUM>), in a different machine (e.g., server <NUM>), etc.) from the device <NUM>. When local, the processor <NUM> may perform the communication to the position calculator <NUM> via an interlink (e.g., bus, data port, etc.) of the device <NUM>. When remote, the processor <NUM> may perform the communication to the position calculator via a network interface, such as via network interface card (NIC), or a wireless transceiver.

In an example, the device <NUM> may be a mobile computing device such as a cellular phone, a smartphone, a laptop, a tablet computer, a personal digital assistant or other electronic device capable of wireless communication. A first access point (AP) <NUM> may, for example, be a base station or a fixed wireless router. The device <NUM> may establish a communication link <NUM> with the first access point <NUM> in order to reach a network <NUM>, such as the Internet. In an example, the device <NUM> may communicate with a access point locations server <NUM> via a link <NUM> over any available connection. For example, the device <NUM> may communicate with the access point locations server <NUM> via the link <NUM> through the first access point <NUM> and the network <NUM>. The link <NUM> may, for example, utilize HyperText Transfer Protocol Secured (HTTPS) and transport layer security (TLS) to prevent the interception or unauthorized manipulation of data exchanged between the device <NUM> and the access point locations server <NUM>. In an example, a cellular base station, such as network equipment <NUM> of <FIG>, may provide the link <NUM> between the device <NUM> and the access point locations server <NUM>.

In an example, a second access point <NUM> or a third access point <NUM> may be within range of the device <NUM>. The device <NUM> may communicate with the first access point <NUM>, the second access point <NUM> or the third access point <NUM>. The device <NUM> may request location information regarding one or more of the first access point <NUM>, the second access point <NUM>, the third access point <NUM>, or any other access point, from the access point locations server <NUM>. In response to the location information request, the access point locations server <NUM> may provide the device <NUM>, via link <NUM>, with the location information corresponding to the requested access point. In an example, the device <NUM> may initiate a location request (e.g., a stage I negotiation of comeback timing) with the first access point <NUM>. The first access point <NUM> may respond to the location request and allocate resources to perform a ToF measurement exchange.

<FIG> is a swim-lane chart illustrating the operation of a method <NUM> for determining a position of a device with an access point in accordance with some embodiments. For example, the initiator <NUM> (e.g., device <NUM> of <FIG>) and the responder <NUM> (e.g., first access point <NUM> of <FIG>) may be configured to perform the method <NUM>, or portions thereof. The method <NUM> may begin with an initial stage I negotiation at <NUM>.

In an example, the initiator <NUM> may transmit a request <NUM> to establish communication with the responder <NUM>. The responder <NUM> may respond with an acknowledgement (ACK) <NUM> indicating the capability of providing location determination services. The responder <NUM> may also transmit a M1 message <NUM> as part of a comeback time negotiation. The initiator <NUM> may transmit an ACK <NUM> to complete the comeback time negotiation and the stage I <NUM> negotiation.

Method <NUM> may continue with a stage II <NUM> sounding exchange. In an example, the initiator <NUM> may transmit a ranging request <NUM> to the responder <NUM>. The responder <NUM> may respond with an acknowledgement (ACK) <NUM> indicating availability to perform the ranging exchange. At <NUM>, time T1, the responder <NUM> may send a first message M1 <NUM> that may include departure timing information, e.g., TOD(M1), to the initiator <NUM>. At <NUM>, an arrival time T2, the initiator <NUM> receives the first message <NUM>, and in response, transmits an ACK <NUM> to the responder <NUM>. The ACK <NUM> may include data that indicates the arrival time T2 of the first message <NUM>. At a departure time T3 <NUM>, the initiator <NUM> sends second message M2 <NUM> to the responder <NUM> that may include the departure time of the second message <NUM>. At <NUM>, arrival time T4, the responder <NUM> receives the second message <NUM> from the initiator <NUM>, and may calculate a range between the initiator <NUM> and the responder <NUM>.

Method <NUM> may continue with a stage III <NUM> with a reporting or timestamp polling phase. For example, the initiator <NUM> may transmit a request <NUM> to the responder <NUM> requesting the range between the initiator <NUM> and the responder <NUM> as calculated by the responder <NUM>, or the request <NUM> may include an indication that an additional ranging exchange is requested. The responder <NUM> may respond with an acknowledgement (ACK) <NUM> indicating the range or capability to perform an additional ranging exchange. The responder <NUM> may also transmit a M1 message <NUM> as part of a next comeback time negotiation. The initiator <NUM> may transmit an ACK <NUM> to complete the comeback time negotiation and the stage III <NUM>.

<FIG> is a swim-lane chart illustrating the operation of a method <NUM> for determining a position of a device with an access point in accordance with some embodiments. Method <NUM> may begin with the elements described in stage I <NUM> and stage II <NUM> of method <NUM> of <FIG>.

Method <NUM> may continue with a stage III <NUM> with a reporting or timestamp polling phase that includes an additional sounding exchange. For example, the initiator <NUM> may transmit the request <NUM> to the responder <NUM> requesting the range between the initiator <NUM> and the responder <NUM> as calculated by the responder <NUM>. The request <NUM> includes an indication that an additional ranging exchange is requested. The responder <NUM> may respond with an acknowledgement (ACK) <NUM> indicating the range and capability to perform an additional ranging exchange. At time T1' <NUM>, the responder <NUM> may transmit a M1 message <NUM> as part of a next sounding exchange. At time T2' <NUM> the initiation <NUM> may receive the message <NUM> that includes the time of departure of the message <NUM>. The initiator <NUM> may transmit an ACK <NUM> to the responder <NUM>. At time T3' <NUM>, the initiator <NUM> may transmit a second message M2 <NUM> to the responder <NUM>. At time T4' the responder may receive the second message M2 <NUM>, and complete the stage III <NUM> by calculate a range between the initiator <NUM> and the responder <NUM> based on times T1', T2', T3' and T4'.

Three types of frames may be utilized to perform a fine timing measurement protocol exchange, such as those described with respect to method <NUM> of <FIG> and method <NUM> of <FIG>. The first frame is a fine timing measurement request (FTMR). The FTMR may be transmitted by an initiator, such as device <NUM> of <FIG>. The FTMR may be utilized to initiate a negotiation of the follow up fine timing measurement exchange details, to report previous fine timing measurement timestamps (T3-T2), and to poll previous fine timing measurement timestamps (T4-T1). The second frame is fine timing measurement <NUM> (FTM1). FTM1 may be transmitted by responder in response to receiving FTMR. The FTM1 may be utilized to report previous fine timing measurement timestamps (T4-T1), to report next follow up fine timing measurement details, and to act as a fine timing measurement frame in case of fine timing measurement exchange. The third frame is fine timing measurement <NUM> (FTM2). FTM2 may be transmitted by the initiator in case of fine timing measurement exchange, and acts as a fine timing measurement frame.

A fine timing measurement request (FTMR) may be based on the FTMR frame structure as discussed in IEEE draft P802. <NUM> REVmc_D. <NUM>-Section <NUM>. In addition to vendor specific IE to complete the added field for the E2E protocol FTMR is a public action frame that utilizes an acknowledgment (Ack).

An example FTMR Frame structure:
Octets:.

An example of the FTMR Vendor specific field.

An example FTMR vendor specific Frame subfields:.

Fine timing measurement <NUM> (FTM1) may be based on IEEE draft standard, such as IEEE P802.11REVmc_D. <NUM> - Section <NUM>. <NUM>, in addition to vendor specific IE to complete the added field for the E2E protocol.

FTM1 may include a public action frame that utilizes an acknowledgement (ACK). The FTM1 may be sent at one of the following three rates: bandwidth (BW) of <NUM>, <NUM>, or <NUM> but not to exceed the recipient's supported channel width; MCS/Rate: HT0 or non-HT Rate 6Mbps duplicate; or spatial streams of either SISO/MIMO that do not exceed recipient's supported MCS se.

FTM1 may set the duration field taking into account: FTM1 + Sifs + Ack + Sifs + M2.

An example FTM1 Frame structure:
Octets:.

An example FTM1 Vendor specific structure:
Octets:.

An example dialog token info (as part of FTM1 Vendor specific) structure:.

An example polled dialog token info (as part of FTM1 Vendor specific) structure:.

An example of FTM1 vendor specific subfields:.

An example of dialog token info (as part of FTM1 vendor specific) subfields:.

An example of polled dialog token info (as part of FTM1 vendor specific) subfields:.

Fine timing measurement <NUM> (FTM2) may be based on an IEEE draft specification such as, IEEE P802. <NUM> REVmc_D. <NUM> - Section <NUM>.

FTM2 may include a public action frame with No-Ack policy. FTM2 may be sent at the same BW, MCS/Rate, and Spatial stream as FTM1.

An example FTM2 Frame structure:
Octets:.

The following table describes an example retry policy and the expected error handling in case of missed or malformed packet arrival:.

<FIG> is a flowchart illustrating an example method <NUM> for determining a position of a device in accordance with some embodiments. In an example, the method <NUM> may be performed by an initiator, such as the device <NUM> of <FIG>, in an attempt to perform a ranging exchange with a responder, such as the access point <NUM> of <FIG>. The ranging exchange may include a time of flight (TOF) protocol that performs a fine-timing measurement (FTM).

If the initiator is not already connected to a wireless network, the method <NUM> may begin with a initiator attempt to discover available wireless networks. The wireless networks may utilize a Wi-Fi or IEEE <NUM> standard protocol, or a protocol such as the current 3GPP, LTE, or TDD-Advanced. At <NUM>, the device may initiate the TOF protocol request with a responder.

At <NUM>, the initiator may negotiate comeback timing for a next FTM exchange with the responder.

At <NUM> the initiator may perform a fine timing measurement exchange with the responder. In an example, the TOF packets received by the initiator from the responder may include data that indicate a time of arrival of the request at the responder, and a time of reply corresponding to the transmission of a response to the request by the responder.

At <NUM>, the initiator may optionally negotiate the comeback timing for a next fine timing measurement exchange.

At <NUM>, the initiator may receive one or more packets from the responder. The one or more packets may include timing data that indicate the request time and the response time as determined by the responder. In an example, the initiator or responder may perform a differential computation based on the exchange between the initiator and the responder to determine a distance between the initiator and the responder.

At <NUM>, the initiator may optionally perform an additional fine timing measurement exchange with the responder.

At <NUM>, the initiator or the responder may determine a location of the initiator. In an example, the location may be an absolute geographic location. In an example, the responder may provide its geographic locations, such as a data structure including a geographic latitude and longitude. In an example, the location may be a relative location with respect to the responder.

These operations of method <NUM> may also be performed by the device <NUM>, access points <NUM>, <NUM>, <NUM>, or a combination of processors in communication with device <NUM> of <FIG>.

Optionally, method <NUM> may include one or more operations defined by any of a variety of network protocols and standards in licensed or unlicensed spectrum bands, including Wi-Fi P2P communications performed in connection with an IEEE <NUM> standard (for example, Wi-Fi Direct communications facilitated by software access points (Soft APs)), 3GPP LTE/LTE-A communications (for example, LTE Direct (LTE-D) communications established in a portion of an uplink segment or other designated resources), machine-to-machine (M2M) communications performed in connection with an IEEE <NUM> standard, and the like.

Though arranged serially in the example of <FIG>, other examples may reorder the operations, omit one or more operations, and/or execute two or more operations in parallel using multiple processors or a single processor organized as two or more virtual machines or sub-processors. Moreover, still other examples may implement the operations as one or more specific interconnected hardware or integrated circuit modules with related control and data signals communicated between and through the modules. Thus, any process flow is applicable to software, firmware, hardware, and hybrid implementations.

<FIG> illustrates a functional block diagram of a UE <NUM> in accordance with some embodiments. The UE <NUM> may be suitable for use as device <NUM> (<FIG>) or device <NUM> (<FIG>). The UE <NUM> may include physical layer circuitry <NUM> for transmitting and receiving signals to and from eNBs using one or more antennas <NUM>. UE <NUM> may also include processing circuitry <NUM> that may include, among other things a channel estimator. UE <NUM> may also include a memory <NUM>. The processing circuitry may be configured to determine several different feedback values discussed below for transmission to the eNB. The processing circuitry may also include a media access control (MAC) layer <NUM>.

In some embodiments, the UE <NUM> may include one or more of a keyboard, a display, a non-volatile memory port, multiple antennas, a graphics processor, an application processor, speakers, and other mobile device elements. The display may be an LCD screen including a touch screen.

The one or more antennas <NUM> utilized by the UE <NUM> may comprise one or more directional or omnidirectional antennas, including, for example, dipole antennas, monopole antennas, patch antennas, loop antennas, microstrip antennas or other types of antennas suitable for transmission of RF signals. In some embodiments, instead of two or more antennas, a single antenna with multiple apertures may be used. In these embodiments, each aperture may be considered a separate antenna. In some multiple-input multiple-output (MIMO) embodiments, the antennas may be effectively separated to take advantage of spatial diversity and the different channel characteristics that may result between each of antennas and the antennas of a transmitting station. In some MIMO embodiments, the antennas may be separated by up to <NUM>/<NUM> of a wavelength or more.

Although the UE <NUM> is illustrated as having several separate functional elements, one or more of the functional elements may be combined and may be implemented by combinations of software-configured elements, such as processing elements including digital signal processors (DSPs), and/or other hardware elements. For example, some elements may comprise one or more microprocessors, DSPs, application specific integrated circuits (ASICs), radio-frequency integrated circuits (RFICs) and combinations of various hardware and logic circuitry for performing at least the functions described herein. In some embodiments, the functional elements may refer to one or more processes operating on one or more processing elements.

Embodiments may be implemented in one or a combination of hardware, firmware and software. Embodiments may also be implemented as instructions stored on a computer-readable storage medium, which may be read and executed by at least one processor to perform the operations described herein. A computer-readable storage medium may include any non-transitory mechanism for storing information in a form readable by a machine (e.g., a computer). For example, a computer-readable storage medium may include read-only memory (ROM), random-access memory (RAM), magnetic disk storage media, optical storage media, flash-memory devices, and other storage devices and media. In these embodiments, one or more processors of the UE <NUM> may be configured with the instructions to perform the operations described herein.

In some embodiments, the UE <NUM> may be configured to receive orthogonal frequency-division multiplexing (OFDM) communication signals over a multicarrier communication channel in accordance with an OFDMA communication technique. The OFDM signals may comprise a plurality of orthogonal subcarriers. In some broadband multicarrier embodiments, eNBs (including macro eNB and pico eNBs) may be part of a broadband wireless access (BWA) network communication network, such as a Worldwide Interoperability for Microwave Access (WiMAX) communication network or a 3rd Generation Partnership Project (3GPP) Universal Terrestrial Radio Access Network (UTRAN) Long-Term-Evolution (LTE) or a Long-Term-Evolution (LTE) communication network, although the scope of the inventive subject matter described herein is not limited in this respect. In these broadband multicarrier embodiments, the UE <NUM> and the eNBs may be configured to communicate in accordance with an orthogonal frequency division multiple access (OFDMA) technique. The UTRAN LTE standards include the 3rd Generation Partnership Project (3GPP) standards for UTRAN-LTE, release <NUM>, March <NUM>, and release <NUM>, December <NUM>, including variations and evolutions thereof.

In some LTE embodiments, the basic unit of the wireless resource is the Physical Resource Block (PRB). The PRB may comprise <NUM> sub-carriers in the frequency domain x <NUM> in the time domain. The PRBs may be allocated in pairs (in the time domain). In these embodiments, the PRB may comprise a plurality of resource elements (REs). A RE may comprise one sub-carrier x one symbol.

Two types of reference signals may be transmitted by an eNB including demodulation reference signals (DM-RS), channel state information reference signals (CIS-RS) and/or a common reference signal (CRS). The DM-RS may be used by the UE for data demodulation. The reference signals may be transmitted in predetermined PRBs.

In some embodiments, the OFDMA technique may be either a frequency domain duplexing (FDD) technique that uses different uplink and downlink spectrum or a time-domain duplexing (TDD) technique that uses the same spectrum for uplink and downlink.

In some other embodiments, the UE <NUM> and the eNBs may be configured to communicate signals that were transmitted using one or more other modulation techniques such as spread spectrum modulation (e.g., direct sequence code division multiple access (DS-CDMA) and/or frequency hopping code division multiple access (FH-CDMA)), time-division multiplexing (TDM) modulation, and/or frequency-division multiplexing (FDM) modulation, although the scope of the embodiments is not limited in this respect.

In some embodiments, the UE <NUM> may be part of a portable wireless communication device, such as a PDA, a laptop or portable computer with wireless communication capability, a web tablet, a wireless telephone, a wireless headset, a pager, an instant messaging device, a digital camera, an access point, a television, a medical device (e.g., a heart rate monitor, a blood pressure monitor, etc.), or other device that may receive and/or transmit information wirelessly.

In some LTE embodiments, the UE <NUM> may calculate several different feedback values which may be used to perform channel adaption for closed-loop spatial multiplexing transmission mode. These feedback values may include a channel-quality indicator (CQI), a rank indicator (RI) and a precoding matrix indicator (PMI). By the CQI, the transmitter selects one of several modulation alphabets and code rate combinations. The RI informs the transmitter about the number of useful transmission layers for the current MIMO channel, and the PMI indicates the codebook index of the precoding matrix (depending on the number of transmit antennas) that is applied at the transmitter. The code rate used by the eNB may be based on the CQI. The PMI may be a vector that is calculated by the UE and reported to the eNB. In some embodiments, the UE may transmit a physical uplink control channel (PUCCH) of format <NUM>, 2a or 2b containing the CQI/PMI or RI.

In these embodiments, the CQI may be an indication of the downlink mobile radio channel quality as experienced by the UE <NUM>. The CQI allows the UE <NUM> to propose to an eNB an optimum modulation scheme and coding rate to use for a given radio link quality so that the resulting transport block error rate would not exceed a certain value, such as <NUM>%. In some embodiments, the UE may report a wideband CQI value which refers to the channel quality of the system bandwidth. The UE may also report a sub-band CQI value per sub-band of a certain number of resource blocks which may be configured by higher layers. The full set of sub-bands may cover the system bandwidth. In case of spatial multiplexing, a CQI per code word may be reported.

In some embodiments, the PMI may indicate an optimum precoding matrix to be used by the eNB for a given radio condition. The PMI value refers to the codebook table. The network configures the number of resource blocks that are represented by a PMI report. In some embodiments, to cover the system bandwidth, multiple PMI reports may be provided. PMI reports may also be provided for closed loop spatial multiplexing, multi-user MIMO and closed-loop rank <NUM> precoding MIMO modes.

In some cooperating multipoint (CoMP) embodiments, the network may be configured for joint transmissions to a UE in which two or more cooperating/coordinating points, such as remote-radio heads (RRHs) transmit jointly. In these embodiments, the joint transmissions may be MIMO transmissions and the cooperating points are configured to perform joint beamforming.

<FIG> is a block diagram illustrating a mobile device <NUM>, upon which any one or more of the techniques (e.g., methodologies) discussed herein may be performed. The mobile device <NUM> may include a processor <NUM>. The processor <NUM> may be any of a variety of different types of commercially available processors suitable for mobile devices, for example, an XScale architecture microprocessor, a Microprocessor without Interlocked Pipeline Stages (MIPS) architecture processor, or another type of processor. A memory <NUM>, such as a Random Access Memory (RAM), a Flash memory, or other type of memory, is typically accessible to the processor <NUM>. The memory <NUM> may be adapted to store an operating system (OS) <NUM>, as well as application programs <NUM>. The OS <NUM> or application programs <NUM> may include instructions stored on a computer readable medium (e.g., memory <NUM>) that may cause the processor <NUM> of the mobile device <NUM> to perform any one or more of the techniques discussed herein. The processor <NUM> may be coupled, either directly or via appropriate intermediary hardware, to a display <NUM> and to one or more input/output (I/O) devices <NUM>, such as a keypad, a touch panel sensor, a microphone, etc. Similarly, in an example embodiment, the processor <NUM> may be coupled to a transceiver <NUM> that interfaces with an antenna <NUM>. The transceiver <NUM> may be configured to both transmit and receive cellular network signals, wireless data signals, or other types of signals via the antenna <NUM>, depending on the nature of the mobile device <NUM>. Further, in some configurations, a GPS receiver <NUM> may also make use of the antenna <NUM> to receive GPS signals.

<FIG> illustrates a block diagram of an example machine <NUM> upon which any one or more of the techniques (e.g., methodologies) discussed herein may be performed. The machine <NUM> may be a personal computer (PC), a tablet PC, a Personal Digital Assistant (PDA), a mobile telephone, a web appliance, or any machine capable of executing instructions (sequential or otherwise) that specify actions to be taken by that machine.

Modules are tangible entities capable of performing specified operations and may be configured or arranged in a certain manner. In an example, the software may reside (<NUM>) on a non-transitory machine-readable medium or (<NUM>) in a transmission signal.

Machine (e.g., computer system or device) <NUM> may include a hardware processor <NUM> (e.g., a processing unit, a graphics processing unit (GPU), a hardware processor core, or any combination thereof), a main memory <NUM>, and a static memory <NUM>, some or all of which may communicate with each other via a link <NUM> (e.g., a bus, link, interconnect, or the like). The machine <NUM> may further include a display device <NUM>, an input device <NUM> (e.g., a keyboard), and a user interface (UI) navigation device <NUM> (e.g., a mouse). In an example, the display device <NUM>, input device <NUM>, and UI navigation device <NUM> may be a touch screen display. The machine <NUM> may additionally include a mass storage (e.g., drive unit) <NUM>, a signal generation device <NUM> (e.g., a speaker), a network interface device <NUM>, and one or more sensors <NUM>, such as a global positioning system (GPS) sensor, camera, video recorder, compass, accelerometer, or other sensor. The machine <NUM> may include an output controller <NUM>, such as a serial (e.g., universal serial bus (USB), parallel, or other wired or wireless (e.g., infrared (IR)) connection to communicate or control one or more peripheral devices (e.g., a printer, card reader, etc.).

The mass storage <NUM> may include a machine-readable medium <NUM> on which is stored one or more sets of data structures or instructions <NUM> (e.g., software) embodying or utilized by any one or more of the techniques or functions described herein. In an example, one or any combination of the hardware processor <NUM>, the main memory <NUM>, the static memory <NUM>, or the mass storage <NUM> may constitute machine-readable media.

While the machine-readable medium <NUM> is illustrated as a single medium, the term "machine readable medium" may include a single medium or multiple media (e.g., a centralized or distributed database, and/or associated caches and servers) that configured to store the one or more instructions <NUM>.

The term "machine-readable medium" may include any tangible medium that is capable of storing, encoding, or carrying instructions for execution by the machine <NUM> and that cause the machine <NUM> to perform any one or more of the techniques of the present disclosure, or that is capable of storing, encoding or carrying data structures used by or associated with such instructions. Non-limiting machine-readable medium examples may include solid-state memories, and optical and magnetic media. Specific examples of machine-readable media may include: non-volatile memory, such as semiconductor memory devices (e.g., Electrically Programmable Read-Only Memory (EPROM), Electrically Erasable Programmable Read-Only Memory (EEPROM)) and flash memory devices; magnetic disks, such as internal hard disks and removable disks; magneto-optical disks; and CD-ROM and DVD-ROM disks.

The instructions <NUM> may further be transmitted or received over a communications network <NUM> using a transmission medium via the network interface device <NUM> utilizing any one of a number of transfer protocols (e.g., frame relay, internet protocol (IP), transmission control protocol (TCP), user datagram protocol (UDP), hypertext transfer protocol (HTTP), etc.). The term "transmission medium" shall be taken to include any intangible medium that is capable of storing, encoding or carrying instructions for execution by the machine <NUM>, and includes digital or analog communications signals or other intangible medium to facilitate communication of such software.

Embodiments may be implemented in one or a combination of hardware, firmware and software. Embodiments may also be implemented as instructions stored on a computer-readable storage device, which may be read and executed by at least one processor to perform the operations described herein. A computer-readable storage device may include any non-transitory mechanism for storing information in a form readable by a machine (e.g., a computer). For example, a computer-readable storage device may include read- only memory (ROM), random-access memory (RAM), magnetic disk storage media, optical storage media, flash-memory devices, and other storage devices and media.

Claim 1:
An apparatus including circuitry to cause a communication station, STA (<NUM>), to:
perform a time negotiation for a fine timing measurement, FTM, exchange stage with a responding station (<NUM>), the time negotiation including transmission of a first message from the STA (<NUM>) to the responding station (<NUM>), and reception at the STA (<NUM>) of a second message from the responding station (<NUM>), the second message including a plurality of timing parameters, the plurality of timing parameters including a parameter to indicate a time interval to perform the FTM exchange stage;
exchange a plurality of measurements for the FTM exchange stage with the responding station according to the plurality of the timing parameters; and
determine a location of the STA (<NUM>) based on the FTM exchange stage.