A system and method characterizes the height of targets in an environment around a vehicle. Signals are transmitted into the environment and return signals are received to determine a track corresponding to a target. For each track, bins are generated, each bin corresponding to a segment of the range, the segments having a gradually increasing size between the minimum range and maximum range. Range and magnitude values of the received return signals are determined for a selected track. A plurality of filled bins are determined, filled bins indicating that a return signal within the selected track has a range value falling within the segment corresponding to said bin. When the number of filled bins exceeds a set threshold, the return signals having range values within the segments corresponding to the filled bins are analyzed to characterize a height of the target.

An iterative method for detecting is provided, with at least one receiver satellite in orbit, a target possessing reflective properties that are different from those of the area in which the target is found, by GNSS reflectometry, wherein the reflected GNSS signals are received by an active antenna of the receiver satellite comprising a plurality of antenna elements, the method comprising a step of determining assumed positions of the target, for which positions it is desired to detect the target, and, forming beams and tracking GNSS signals in accordance with these assumptions.

A multi-static radar system provides surveillance. The radar system includes a plurality of radar receivers and a plurality of radar transmitters arranged in a multi-static configuration to form at least one radar cell to provide an area of radar coverage within the cell.

A method for creating a virtual reception channel in a radar system includes an antenna possessing two physical reception channels (1.sub.r, 2.sub.r) spaced apart by a distance d in a direction x, two emission channels (1.sub.e, 2.sub.e) spaced apart by the same distance d in the same direction x and processing means, the method comprising: dynamically selecting two different waveforms, the waveforms being orthogonal to each other; generating a radar pulse of given central wavelength in each emission channel, each of the emission channels emitting one of the two different waveforms; acquiring with the reception channels echoes due to pulses emitted by the emission channels and reflected by at least one target; compressing the pulses by matched filtering of the echoes acquired by each physical reception channel, this involving correlating them with each of the waveforms generated in the emission channel; and repeating steps a) to c) while randomly changing one of the values of each of the phase codes associated with the generated waveforms until the level of the sidelobes of all the compressed pulses has stabilized; and radar system for implementing such a method.

A system may include a processor configured to: receive ambient data from an environment; calculate an average amplitude of the ambient data as a measure of a noise floor; receive a signal of interest found by the signal exceeding a noise riding threshold, the noise riding floor being an upward offset from the noise floor; calculate a running average for amplitude and frequency of the signal of interest; calculate a running variance for the amplitude and the frequency of the signal of interest; use the running average and the running variance to provide an adjustment to limits for modulation detection; use an offset from the noise riding threshold to provide a signal qualification minimum amplitude; and qualify the signal of interest based at least on the signal qualification minimum amplitude.

The present invention is directed to a method for processing radar signals in a distributed array radar that includes a first airborne platform and at least one second airborne platform. Doppler filtered radar return samples are obtained and a weight value is calculated as a function of first clutter signals and second clutter signals. The weight value is employed in a weight vector that is computed, as well, from a steering vector that need not be matched to the target vector. The weight vector is applied to a signal vector corresponding to the Doppler filtered radar return samples. An open loop feedback is implemented and configured to create beam pattern nulls at angles corresponding to the plurality of first interference signals within each of the Doppler bins without substantially tracking a position or velocity of the first airborne platform or the at least one second airborne platform.

An occupancy detection apparatus and a method for controlling the same are disclosed. The occupancy detection apparatus may include a transmitter including one transmission antenna for outputting a transmission signal, a receiver including a first reception antenna and a second reception antenna, each for receiving a reflected signal corresponding to the transmission signal, and a processor for eliminating a background signal corresponding to a background from each of the reflected signals, and extracting a signal reflected from an occupant from each of the reflected signals by extracting a correlation between the transmission signal and the reflected signal free of the background signal.

A radar system provides information relating to a three-dimensional field of surveillance (FoS) having a volume exceeding one cubic kilometre. The radar system includes a radar transmitter and radar receiver arranged to provide persistent surveillance of the FoS. Each radar return signal received within a sequence of time periods is processed. An associated signal information is stored in a memory in association with information identifying at least one of a respective beam in which that return signal was received and a respective receiver element at which that respective return signal was received.

A computer-implemented method is provided for maximizing surveillance volume in a radar system. This includes determining saturation range probability f.sub.sat; determining sensitivity probability f.sub.sens; calculating surveillance volume from multiplying the saturation range probability by the sensitivity probability as V.sub.s=f.sub.satf.sub.sens; and adjusting the radar system to maximize the surveillance volume.

A radar system includes a radio frequency (RF) circuit to generate a transmit signal and to receive a corresponding receive signal from a target during rainfall or snowfall conditions, and a signal processing circuit coupled to the RF circuit to generate an adaptive filter threshold in response to the rainfall or snowfall conditions, and to generate a valid target signal in response a portion of the receive signal above the adaptive filter threshold.