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.

In accordance with a first aspect of the present disclosure, a transponder is provided, comprising: a frequency detector configured to monitor an output frequency of a clock-stop sensor of said transponder, wherein said frequency detector is further configured to determine if said output frequency falls within a response detection frequency range of an external reader, and a frequency shifter configured to shift, in response to the frequency detector determining that the output frequency falls within said response detection frequency range, said output frequency to a value outside said response detection frequency range. In accordance with a second aspect of the present disclosure, a corresponding method of operating a transponder is conceived. In accordance with a third aspect of the present disclosure, a corresponding computer program is provided.

Various communication systems may benefit from suitable architectures. For example, L-band radio frequency (RF) architectures may be beneficial to systems including avionics systems. A system can include a mode-s function as well as a traffic alert and collision avoidance system function separate from the mode-s function. The system can further include a directional antenna in reception and transmission connection with the traffic alert and collision avoidance system function. The system can additionally include an omni-directional antenna in reception and transmission connection with the mode-s function.

A radar includes an antenna having a radiating pattern forming a sum channel, a radiating pattern forming a difference channel and a pattern forming a control channel, and generates at least interrogation messages on the sum channel and interrogation messages on the control channel; transmits messages via the sum channel and via the control channel respectively, and receives and processes signals received via the sum, difference, and control channels, configured for detecting replies of targets on the signals received via the sum and difference channels and carrying out monopulse processing and RSLS processing on the replies. The transmission is configured such that, for each target, the width of the beam for transmitting interrogations and receiving mode S selective replies is controlled based on the movement window of the target and position of the axis of the antenna in the window, to provide detection of the target by reducing the number of selective interrogations by a selective sub-interrogation of the target while ensuring precise positioning in azimuth: by pre-locating the target at the edge of the main reception lobe of the antenna by deviation measurement between the signals received on the difference and sum channels; and by selectively re-interrogating the pre-located target in mode S by calculation of the roll-call signal nearest to the centre of the main lobe to ensure precision in azimuth, without any other unnecessary supplementary interrogation.

A ranging method includes: sending a first signal, where a time at which the first signal is sent from a first UE is a first time; receiving a second signal sent by a second UE, where a time at which the second signal reaches the first UE is a second time; and determining a distance between the first UE and the second UE according to the first time, the second time, and a first time difference, where the first time difference is a difference between a third time at which the second UE sends the second signal and a fourth time at which the second UE receives the first signal.

An electronic device and a method of the electronic device for performing localization in a wireless communication system are provided. The electronic device and method comprise: receiving, from a plurality of anchor nodes, signals for the localization; performing ranging measurements of the signals based on a range and an angle of arrival (AoA) of the signals; determining whether at least one of the plurality of anchor nodes is not detected based on the ranging measurements; determining, based on a determination that the at least one anchor node is not detected based on the ranging measurements, whether at least one other anchor node in the plurality of anchor nodes is located on a line of sight (LOS) from the electronic device, wherein the LOS is determined based on the AoA of the signals; and performing the localization based on the at least one other anchor node.

An athlete monitoring system includes body position beacons, a localized radar system, a foot force detection system, and a processing module. The beacons are positioned at various locations on the body of the athlete. The localized radar system creates a localized radar coordinate system in which the athlete is positioned and, at a first sampling rate, produces frames of body position data based on determining location of the beacons within the localized radar coordinate system. The foot force detection system generates frames of left foot force data and frames of right foot force data. The processing module correlates the frames of body position data, the frames of left foot force data, and the frames of right foot force data to produce integrated ground-body interaction data and athletic movement data.

A foot force detection system includes variable capacitors, drive sense circuits, a processing module, and a power unit. A drive sense circuit supplies a reference signal to the variable capacitor. It then generates a sensed signal regarding a characteristic of the variable capacitor based on the reference signal. It then converts the sensed signal into a digital signal. The processing module generates a digital impedance value for the variable capacitor based on the digital signal and writes the digital impedance value in memory. The power unit include a battery and a power harvesting circuit, where the battery and/or the power harvesting circuit provide power for the foot force detection system.

The disclosure provides some embodiments for securing long training field (LTF) sequence. A responding station (RSTA) configures a location management report (LMR) frame. The LMR frame is configured to include an LMR in respect of a previous measurement, and data to be used to generate a null data packet (NDP) for a current measurement that is to be performed following the previous measurement. The RSTA further encrypts the LMR frame using protected management frames (PMF) scheme, and transmits the encrypted LMR frame to an initiating station (ISTA) for generating an LTF sequence for the current measurement. In response to receiving an NDP announcement (NDPA) and an NDP for the current measurement from the ISTA, the RSTA generates an NDP for the current measurement based on the NDPA and the data using CCMP, and transmits the NDP to the ISTA.

A position detection system includes a measurement unit that obtains a measurement value related to transmission and reception of radio waves from when the radio waves are transmitted from one of first and second communication devices to the other one of the first and second communication devices to when the one of the first and second communication devices receives a response to the radio waves to detect a positional relationship of the first and second communication devices. The measurement unit obtains multiple measurement values by performing communication to obtain the measurement value a multiple number of times in which a parameter of the communication is changed.