The secondary radar includes an antenna having a radiation pattern forming a sum channel, designated SUM, a radiation pattern forming a difference channel, designated DIFF, and a pattern forming a control channel, designated CONT, the targets are located by implementing the following steps: detecting ADS-B squitters received via the CONT channel, via the SUM channel and via the DIFF channel; measuring at least the power of the squitters and their azimuth with respect to the radar; the location of a target transmitting ADS-B squitters being computed by exploiting at least the detection of one ADS-B squitter, in light of the latitudinal and longitudinal position of the radar and of the azimuthal measurement with respect to the radar, the position cell, designated the CPR cell, coded in the squitter being selected via the azimuthal measurement.

Disclosed is an ultra-wideband integrated circuit having a transmitter, a receiver, and a non-volatile memory configured to store a time-of-flight between the transmitter and receiver. Also included is an interface configured to communicate with a processor configured to calculate the time-of-flight. Further included is a digital transceiver configured, in response to a loopback mode, to cause the transmitter to transmit a plurality of ultra-wideband frames directly to the receiver, measure a time-of-flight for each of the plurality of ultra-wideband frames received by the receiver and generate a data set for calculating the time-of-flight associated with each measured time-of-flight, send the data set to the processor, receive from the processor the time-of-flight calculated from the data set, and store the time-of-flight in the non-volatile memory.

A system for keyless entry applications using beamforming transmission in a millimeter wave spectrum in an environment. A memory with data including values indicative of link attributes associated with beam signal measurements with states of devices and states of environments. The states of the devices for each device including types of user behavior, locations and poses in each environment. Control circuitry performs beam training with a target device associated with at least one keyless entry application in the environment to measure beam signal values and environmental responses for different beams transmitted over the different beam angles. Selects, in response to the beam training, at least one dominant angle for a beamforming communication with the target device. Estimates, a state of the target device associated with the at least one keyless entry application or a state of the environment, corresponding to environmental responses for different beams estimated during the beam training.

A process for detecting a portable user device in a predetermined zone on the inside or outside of a vehicle by a detection device onboard the vehicle. The high-frequency, BLE type communication includes a first signaling mode and a second communication mode, the first mode including: positioning the portable device at a predetermined fixed distance from the detection device, transmitting a signal by the detection device with predetermined transmission power on a channel. As long as the detection device is receiving a response signal from the portable device, repeating transmission of the signal at the same transmission power on other channels, otherwise, repeating transmission of the signal on a channel with reduced transmission power, and if the detection device no longer receives a response signal, comparing the transmission power to a predetermined threshold transmission power, and applying a correction to the transmission power during the second mode.

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 feature detection system, the system comprising: at least one processor in operative communication with a signal source, said processor further comprising at least one non-transitory storage medium, wherein at least one non-transitory storage medium contains instructions configured to cause the processor to: apply a joint group sparse denoising and delay estimation approach to a signal received from said signal source; and output statistics regarding the signal, wherein the joint group sparse denoising and delay estimation approach comprises; using the following equation:

[00001]$\left\{x^{*},{\tau }^{*}\right\}=\underset{x,\tau }{\mathrm{argmin}}\left\{\frac{1}{2}\underset{j=1}{\overset{M}{.Math.}}{.Math.y_j-x.Math.}_2^2+\underset{i=0}{\overset{N}{.Math.}}{\lambda }_i{\phi }_i\left(D_i^{l_i}x\right)\right\}$

where: ϕ.sub.i are regularization functions; ∥y−x∥.sub.2.sup.2 is a data-fidelity term and, in embodiments, is chosen as the least-square term; l.sub.i are real numbers; D.sub.i are operators, which may be linear filters that can be written in matrix form; λ.sub.i are regularization parameters; and x*,τ* represent estimates of at least one transmitted pulse and associated delay, and solving the equation for multiple values of ϵ; choosing a vector, x, such that a cost function comprising the data fidelity term and regularization function is minimized; determining the ϵ that corresponds to the x that minimizes the cost function; and calculating the pulse width of the received signal, which corresponds to the desired estimate of the vector, x.

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.

Access Point (AP) placement using Fine Time Measurement (FTM) may be provided. First, a plurality of Time-of-Flight (ToF) values between a first service end point and a second service end point may be determined. Each one of the plurality of ToF values may be derived from packets transmitted via different beamforming vector patterns at the first service end point and the second service end point. Then a minimum ToF value of the plurality of ToF values may be determined. Next, a distance between the first service end point and the second service end point may be determined based on the minimum ToF value.

A method for determining reception window timing using a measuring station receiving an antenna beam width, receiving an antenna tilt angle, receiving an altitude A, determining a far projection angle Δf, determining a near projection angle Δn, and determining a far projection range corresponding to the far projection angle Δf and based at least upon the values of Δf and A. The method further includes determining a near projection range corresponding to the near projection angle Δn and based at least upon the values of Δn and A, determining an end time of a reception window based at least upon the value of the far projection range the reception window being a window of time in which a response from the target station is expected to be received, and determining a start time of the reception window based at least upon the value of the near projection range.

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.