A communications system, including at least one tag and a plurality of beacons. The tags are configured to detect beacon advertisement messages, initiate a connection with at least one of the plurality of and transmit a Constant Tone (CT) to the at least one of the plurality of beacons. The tag is further configured to determine a location thereof based on the sampled CT from both the beacon and the tag and then report the location via the one of the beacons and/or an access point. Phase ranging mitigation techniques which include hop duplication, hop interpolation and ADC DC offset correction are employed so as to provide more accurate ranging values even in the case where there are many other devices in local proximity and which are competing for use of the same RF channels as those used by the tags and beacons.

A localization method for locating a target that is coupled with a locator transponder associated with a permanent identification code permanently assigned to the locator transponder is provided. The localization method includes: a) transmitting a spread spectrum paging signal carrying the permanent identification code and a shorter temporary identification code temporarily assigned to the locator transponder; b) receiving the spread spectrum paging signal and extracting the temporary identification code carried by the received spread spectrum paging signal; c) transmitting radar signals towards area(s) of earth's surface or sky and receiving echo signals therefrom; d) upon reception by the locator transponder of radar signal(s), generating and transmitting a sequence of watermarked radar echo signals in which a spread spectrum watermarking signal is embedded that includes the temporary identification code; e) carrying out localization operations; f) transmitting frequency-synchronization-aid signal(s); g) receiving the frequency-synchronization-aid signal(s) and estimating a frequency drift affecting a reference frequency provided by a local oscillator of the locator transponder; wherein the locator transponder transmits the sequence of watermarked radar echo signals by using a transmission carrier frequency obtained based on the reference frequency provided by the local oscillator and on the estimated frequency drift.

In accordance with various implementations, a radar system comprising a non-line of sight (NLOS) module to enhance operation of the radar system is provided. In various embodiments, the NLOS module is a radar repeater module with phase shifters to generate an indication of an object detected in a NLOS area. In various embodiments, the NLOS module includes a reflector structure configured to reflect or redirect radar signals from a train on the tracks into a NLOS area. The NLOS module can include a receive antenna, a transmit antenna configured to transmit one or more received radar signals into a NLOS area, and a phase shifting module for applying a phase shift to a radar signal reflected from an object in the NLOS area that is outside an operational range of the radar unit.

A multicarrier phase ranging system and method are provided. Generally, the method includes performing a handshake between first and a second transceiver to negotiate a list of channels and a start-time for a multicarrier phase ranging process. The process includes in a first cycle exchanging a Constant Tone (CT) between the first and second transceiver in a first epoch on a first channel, and processing the CT received in the first and second transceiver to measure a difference in phase between the CT received and a reference signal. The CT received is checked for interference using software or hardware in either or both of the first and second transceiver. If no interference is detected the first and second transceiver switch to another channel and exchange the CT at a next epoch. If interference is detected, at least one channel is skipped for at least a subsequent epoch.

A method and device for detecting an illegal unmanned aerial vehicle (UAV) using a radio wave wall are provided. The method includes generating a radio wave wall between a plurality of reconnaissance UAVs that include a first reconnaissance UAV and second reconnaissance UAVs, using one or more wireless signals transmitted and received between the plurality of reconnaissance UAVs, and determining whether an illegal UAV enters the radio wave wall based on radio signal strengths of wireless signals received from the second reconnaissance UAVs.

A wireless animal location system is provided that identifies a location of a pet roaming within an environment using a single base unit. The wireless animal location system tracks and manages animal behavior in the environment using information of pet location.

A spatial location positioning method for an elevator, a spatial location positioning system for an elevator, and an elevator. The spatial location positioning method for the elevator includes transmitting near-field wireless communication signals in preset areas of the elevator; receiving response signals of a target object to the near-field wireless communication signals, and analyzing signal AOA (angle of arrival) information from the response signals; and determining current location of the target object according to the signal AOA information.

Disclosed are techniques for time-multiplexing between sensing and adjacent signal transmission functionalities on the same hardware platform, such as a chipset supporting a main ranging device in passive entry passive start (PEPS) applications using secure multi-carrier phase-based ranging solutions to estimate the range between the main ranging device and a target device. The supporting chipset may be configured to operate as a sensor to receive continuous tone (CT) signals or round-trip time (RTT) packets exchanged between the main ranging device and the target device in a timeslot of a ranging cycle to improve the accuracy of the range estimates. In a different timeslot, the supporting device may operate as a transmitter to transmit CT signals or RTT packet on a channel adjacent to the channel used by the main ranging device to protect the CT signals or the RTT packets transmitted from the main ranging device against symbol level attacks.

Disclosed are techniques for determining round-trip times (RTTs) between a user equipment (UE) and multiple base stations. In an aspect, the UE transmits an RTT measurement signal whose arrival time is measured by each of the base stations, and each of the base stations returns an RTT response signal whose arrival times are measured by the UE. In another aspect, the base stations each transmit an RTT measurement signal and the UE returns an RTT response signal. The receiver of the RTT measurement signal may include the measured arrival time in a payload of the RTT Response signal. Alternatively, the measured arrival time(s) of the RTT Measurement signal(s) and the transmission time(s) of the RTT Response signal(s) are sent in a separate message. The RTT signals can be wideband signals using low reuse resources.

Aspects of the of the disclosure relate to a non-contact physiological motion sensor and a monitor device that can incorporate use of the Doppler effect. A continuous wave of electromagnetic radiation can be transmitted toward one or more subjects and the Doppler-shifted received signals can be digitized and/or processed subsequently to extract information related to the cardiopulmonary motion in the one or more subjects. The extracted information can be used, for example, to determine apneic events and/or snoring events and/or to provide apnea or snoring therapy to subjects when used in conjunction with an apnea or snoring therapy device. In addition, methods of use are disclosed for sway cancellation, realization of cessation of breath, integration with multi-parameter patient monitoring systems, providing positive providing patient identification, or any combination thereof.