A ground map monitor method comprises obtaining positions of communication nodes in a communications network, selecting transmission and reception nodes from the communication nodes, and measuring bistatic signals between the transmission and reception nodes to determine nominal signal performance characteristics for the bistatic signals, including reflected signal time delays, frequency shifts, and power levels. The method further comprises monitoring the bistatic signals for changes to nominal signal performance characteristics. The method uses discriminators between the nominal signal performance characteristics and a current performance level of the bistatic signals, and compares the discriminators against performance thresholds, to determine whether current signal performance characteristics have varied from their nominal levels. An alert signal is broadcast that a section of a navigation map is not useable for navigation of a vehicle if changes in the current performance level of the bistatic signals exceeds the performance thresholds.

Provided are a radar communication integrated cooperative detection method and apparatus based on beam power distribution. The method comprises: determining a farthest detection distance and a detection volume of a single radar in a radar communication integrated system during transmitting of a detection beam when the radar has a preset transmit power; determining a communication success probability of each pair of radars during transmitting communication beams; determining a detection area volume of each pair of radars under different power distribution coefficients based on the farthest detection distance, the detection volume, a different power distribution coefficient of the single radar, and the communication success probability of each pair of radars; determining a power distribution coefficient corresponding to a largest detection area volume from different detection area volumes as a current power distribution coefficient; and determining total detection volume of the radar communication integrated system based on the detection area volume of each pair of radars and the current power distribution coefficient.

A micro impulse radar (MIR) system includes an MIR transceiver circuit configured to transmit, towards a subject, at least one transmitted radar signal, and receive at least one radar return signal. The system includes a control circuit configured to generate a control signal defining a radar signal parameter of the at least one transmitted radar signal, provide the control signal to the MIR transceiver circuit to cause the MIR transceiver circuit to transmit the at least one transmitted signal based on the radar signal parameter, and determine, based on the at least one radar return signal, a physiological parameter of the subject.

This disclosure provides systems, methods and apparatus, including computer programs encoded on computer storage media, for multistatic radar communications. In some implementations, a transmitting device may transmit, to a receiving device, a radar alert frame followed by a codeword and one or more radar pulses. The radar pulses are transmitted, using beamforming, in a number of directions. The timing information indicates a timing offset or delay between one or more codewords of the codeword sequence and the beginning of the radar pulses. The receiving device may detect one or more codewords of the codeword sequence and an echo of at least one of the radar pulses, and determine the time at which the corresponding pulse was transmitted by the transmitting device. The receiving device may compare the timing of the echo with the timing of the transmitted pulse to determine a relative distance of an object that produced the echo.

A system identifies and localizes an object. The system contains a bistatic FMCW radar sensor system having two FMCW radar sensors and is configured to operate coherently or quasi-coherently and to emit a series of repeating ramp signals. An active RFID transponder is disposed on an object to be identified and to be localized and is configured to produce a modulated bistatic backscatter signal. A ramp signal sent out by the radar sensors at a ramp repetition frequency is modulated with an amplitude modulation signal, the modulation frequency is less than half the ramp repetition frequency. An evaluation unit establishes an association between a beat frequency and the modulation frequency of the active RFID transponder, which modulation frequency is already known, on the basis of the modulated bistatic backscatter signal by two Fourier transforms of the modulated backscatter signal according to the frequency and to the amplitude.

A surface-based transmitter system for assisting determination of vehicle location is presented. The system comprises a set of radio frequency (RF) transmitter nodes that, when deployed at different respective locations, are configured to output a sequence of respective RF pulses with a predefined inter-pulse delay between each pair of consecutive RF pulses in the sequence, wherein the pre-defined inter-pulse delay is longer than one microsecond. The set of RF transmitter nodes include at least a first RF transmitter node, a second RF transmitter node, a third RF transmitter node, and a fourth RF transmitter node, which are configured to output a first RF pulse, a second RF pulse, a third RF pulse, and a fourth RF pulse, respectively, of the sequence of RF pulses.

Systems and methods for Wi-Fi sensing using UL-OFDMA are provided. Wi-Fi sensing systems include sensing devices and sensing transmitters configured to communicate through radio-frequency signals. Initially, first channel resources are allocated to first expected transmissions from the sensing transmitters and first sensing trigger message to trigger first series of sensing transmissions from the sensing transmitters is transmitted. Further, a first series of sensing transmissions is received, and the first series of sensing measurements are generated. Thereafter, identification of feature of interest is obtained and a selection of sensing transmitters is determined. Second channel resources are allocated to second expected transmissions from the selection of sensing transmitters. A second sensing trigger message to trigger a second series of sensing transmissions from the selection of the sensing transmitters is provided. A series of sensing transmissions is received, and a second series of sensing measurements is generated based on the second series of sensing transmissions.

A cellular network system and method provided herein are directed to generating an area topographic map of a surrounding area of the cellular network system. The cellular network system comprises a transmitter, a receiver, memory, and one or more processors (processors) communicatively coupled to the transmitter, the receiver, and the memory. The memory stores computer-executable instructions that, when executed by the processors, perform certain operations. The transmitter transmits in a target direction a first signal, which is a communication signal intended for a user equipment (UE) and the receiver receives a second signal. The processors determine whether the second signal is a reflected signal associated with the first signal, determine topographic data associated with the surrounding area of the cellular network system in the target direction based at least in part on the second signal, and generate the area topographic map of the surrounding area based on the topographic data.

A radar system for motor vehicles, with a plurality of transmit/receive units arranged on separate installation supports for installation at various locations in the motor vehicle, an evaluation system for evaluating the radar signals received on a plurality of channels in a plurality of processing steps, a first processing step delivering a digital time signal for each channel, which digital time signal represents the received radar signal, and a final processing step delivering as the result location data for individual radar objects and at least the final processing step being implemented for the plurality of transmit/receive units in a central evaluation unit with which the transmit/receive units in each case communicate via a raw data interface. The each of raw data interfaces has a serializer, which is configured to transfer raw data from the plurality of channels of the transmit/receive unit in question serially to the central evaluation unit.

A bi-static radar system configured for coherent detection of a radar-signal includes a plurality of radar-transceivers, a controller, and a communications device. The plurality of radar-transceivers is characterized as physically spaced apart with respect to each other. The controller is in communication with the each of the radar-transceivers and is configured to coherently operate each of the radar-transceivers. The communications device communicates both a reference-clock signal and a frame-sync signal from the controller to each of the plurality of radar-transceivers whereby the plurality of radar-transceivers operate coherently. Alternatively, the system may include a reference-signal generator, a transmitter, and a plurality of receivers. The reference-signal generator generates a reference-signal characterized by a reference-frequency proportional to a fraction of a radar-frequency of a radar-signal transmitted. The transmitter generates the radar-signal at the radar-frequency based on the reference-signal. The plurality of receivers operates coherently to detect the radar-signal based on the reference-signal.