Methods, apparatus and systems for wireless tracking with graph-based particle filtering are described. A described wireless monitoring system comprises a transmitter transmitting a series of probe signals, a receiver, and a processor. The receiver is configured for: receiving the series of probe signals modulated by the wireless multipath channel and an object moving in a venue, and obtaining a time series of channel information (TSCI) of the wireless multipath channel from the series of probe signals. The processor is configured for: monitoring a motion of the object relative to a map based on the TSCI, determining an incremental distance travelled by the object in an incremental time period based on the TSCI, and computing a next location of the object at a next time in the map based on at least one of: a current location of the object at a current time, the incremental distance, and a direction of the motion during the incremental time period.

A method by which a terminal operates in a wireless communication system, according to one embodiment, comprises the steps of: receiving time difference of arrival (TDoA) slots from anchor nodes (ANs); and measuring the position of the terminal by using the TDoA slots, wherein the TDoA slots include control information of the ANs and positioning reference signals (PRSs) of the ANs.

A method by which a terminal operates in a wireless communication system, according to one embodiment, comprises the steps of: receiving time difference of arrival (TDoA) slots from anchor nodes (ANs); and measuring the position of the terminal by using the TDoA slots, wherein the TDoA slots include control information of the ANs and positioning reference signals (PRSs) of the ANs.

A system and bent-pipe transponder component for determining a location of an individual or object in three dimensional space. The system includes a transmitter configured to transmit a first wireless electromagnetic signal at a first frequency and at least one transponder that is configured to responsively emit a second wireless electromagnetic signal having a second frequency that is frequency-shifted from the first frequency. An included receiver detecting the first and second wireless electromagnetic signals is configured to provide an output of location information for the at least one transponder. A bent-pipe transponder component may include a receiving antenna, an emitting antenna, and a frequency shift stage comprising an oscillator and a first mixer, with the frequency stage mixing a received first wireless electromagnetic signal with the output of the oscillator via the first mixer to produce the emitted second wireless electromagnetic signal.

A system and bent-pipe transponder component for determining a location of an individual or object in three dimensional space. The system includes a transmitter configured to transmit a first wireless electromagnetic signal at a first frequency and at least one transponder that is configured to responsively emit a second wireless electromagnetic signal having a second frequency that is frequency-shifted from the first frequency. An included receiver detecting the first and second wireless electromagnetic signals is configured to provide an output of location information for the at least one transponder. A bent-pipe transponder component may include a receiving antenna, an emitting antenna, and a frequency shift stage comprising an oscillator and a first mixer, with the frequency stage mixing a received first wireless electromagnetic signal with the output of the oscillator via the first mixer to produce the emitted second wireless electromagnetic signal.

A system for locating an optimal location of a reception antenna that has an unmanned aerial vehicle (UAV), a wireless internet service provider (WISP) tower configured for transmitting radio signals, and an antenna removably coupled to the unmanned aerial vehicle, the antenna configured for receiving the radio signals. Further, the system has a processor for automatically flying the UAV to a height, for rotating the unmanned aerial vehicle at the height and detecting the radio signals from the at least one WISP tower as the UAV rotates to determine an optimal azimuth, and if the radio signals received are not conducive for the provision of wireless services at the height, the processor moves the UAV to different heights and rotates the UAV until radio signals received are conducive for the provision of wireless services thereby determining an optimal azimuth and location altitude range for a reception antenna.

A system for locating an optimal location of a reception antenna that has an unmanned aerial vehicle (UAV), a wireless internet service provider (WISP) tower configured for transmitting radio signals, and an antenna removably coupled to the unmanned aerial vehicle, the antenna configured for receiving the radio signals. Further, the system has a processor for automatically flying the UAV to a height, for rotating the unmanned aerial vehicle at the height and detecting the radio signals from the at least one WISP tower as the UAV rotates to determine an optimal azimuth, and if the radio signals received are not conducive for the provision of wireless services at the height, the processor moves the UAV to different heights and rotates the UAV until radio signals received are conducive for the provision of wireless services thereby determining an optimal azimuth and location altitude range for a reception antenna.

A method and system for phase shift based time of arrival (TOA) reporting in passive location ranging is herein provided. According to one embodiment, a method includes measuring, by a responder station (RSTA), a first phase shift time of arrival (PS-TOA); measuring, by an initiator station (ISTA), a second PS-TOA; reporting, by the RSTA, the first PS-TOA, reporting, by the ISTA, the second PS-TOA; broadcasting, by the RSTA, time stamps; and determining, by a passive station (PSTA), a differential distance between the PSTA and a pair of the RSTA and ISTA based on the first PS-TOA, the second PS-TOA, and the broadcast time stamps.

A method and system for phase shift based time of arrival (TOA) reporting in passive location ranging is herein provided. According to one embodiment, a method includes measuring, by a responder station (RSTA), a first phase shift time of arrival (PS-TOA); measuring, by an initiator station (ISTA), a second PS-TOA; reporting, by the RSTA, the first PS-TOA, reporting, by the ISTA, the second PS-TOA; broadcasting, by the RSTA, time stamps; and determining, by a passive station (PSTA), a differential distance between the PSTA and a pair of the RSTA and ISTA based on the first PS-TOA, the second PS-TOA, and the broadcast time stamps.

A method for determining a time difference of arrival, and a communication device and system, where neighbor cells for positioning are determined for a target terminal by a positioning server, then cell identities of the neighbor cells and beam polling configuration information of the neighbor cells are transmitted to the target terminal, so that the target terminal may detect a Positioning Reference Signal (PRS) beam transmitted by a corresponding neighbor cell according to the beam polling configuration information, and a time difference of arrival of PRS beams transmitted by one neighbor cell and another neighbor cell is calculated.