A radar system and method are provided for reducing multipath interference signals. The multipath interference signals can be reduced by the radar system emitting electromagnetic waves that creates a null in the direction of expected multipath interference signals, such that the multipath interference signals are void (or substantially void) from signals received by the radar system.

A system and method for using coherent aggregated bandwidth over multiple transmissions for improved performance of precision guidance and positioning and of object tracking systems. Angular offset (Az/El) estimations are strongly impacted by interference between direct and (comparable amplitude) ground-reflected signals. In rough ground situations, there could be many ground reflected signals. Bandwidth aggregation as used herein achieves sharper range sidelobes and smaller magnitude multipath interference terms resulting in increasingly accurate interferometric results.

Each pattern being associated with a reception channel, over a given time period, the unsolicited asynchronous replies, of long ADS-B squitters type, transmitted by targets present in the airborne environment of the radar, are detected, each of the squitters containing position information on the target which transmits it; for each detection, the long ADS-B squitter is decoded to check that the detected target is located in accordance with the position information contained in the squitter, the non-conforming detections being rejected; for each detection retained, the time of the detection, the value of the azimuth of the main beam of the antenna and the received power value on each of the reception channels is associated with the detection, the position information contained in the squitters giving the elevation segment wherein the detection is situated; the values obtained over the period being stored, the measured patterns being sampled, by elevation segment, from the stored values.

A frequency modulated continuous wave (FMCW) radar system includes an antenna array having C antennas where (C=A+B−1), a first integrated circuit (IC) device including A first sensor inputs, and a second IC device including B second sensor inputs. The first sensor inputs are coupled to a first A of the antennas, and the second sensor inputs are coupled to a last B of the antennas such that a common one of the first sensor inputs and a common one of the second sensor inputs are both coupled to a common antenna. Each IC device receives reflected signals on each sensor input, and mixes the reflected signals to associated baseband signals based upon a local oscillator (LO) signal. Each LO signal has a different phase shift. The LO signals are based upon a common LO signal.

In imaging radar, examples are directed to uses of multiple sets of transmit antenna included with transceiver circuitry, for transmitting in a plurality of modes. Transmissions may involve having at least one transmit antenna, from each of at least two of the multiple sets, to transmit continuous-wave energy concurrently (simultaneously) in one or more of the plurality of different modes. Transceiver circuitry may include multiple receive antennas which may be receiving reflections of the continuous-wave energy from various targets. Signals from the multiple receive antennas may route to signal processing circuitry. The signal processing circuitry may respond to the received reflections of the continuous-wave energy by assessing differences in antenna gain and/or phase due to transmit antenna position associated with the received reflections. This signal processing assessment may mitigate or resolve at least one spatial ambiguity in at least one direction of arrival dimension associated with the received reflections.

A radar system for detecting the surroundings of a motor vehicle, the radar system includes a plastic-based antenna having a front side facing a cover. The plastic-based antenna has a plurality of individual antennas for transmitting and/or receiving radar signals to detect objects and/or determining angles thereof. The front side between the individual antennas is configured to be at least partially not reflective on a surface thereof such that interference waves on the surface of the plastic-based antenna and/or reflections between the plastic-based antenna and the cover are suppressed or the negative effects thereof on the determination of angles are at least reduced.

In an azimuth estimation device, a center generation unit configured to generate, for each peak bin extracted by the extraction unit, a center matrix which is a correlation matrix obtained using values of the same peak bin collected from all of transmitting/receiving channels. A surrounding generation unit is configured to generate, for each of one or more surrounding bins of each of the peak bins, a surrounding matrix which is a correlation matrix obtained using values of the same surrounding bin collected from all of the transmitting/receiving channels. An integration unit is configured to generate, for each peak bin, an integrated matrix which is a correlation matrix obtained by weighting and adding the center matrix and the one or more surrounding matrices. An estimation unit is configured to execute an azimuth estimation calculation using the integrated matrix generated by the integration unit.

A radar device includes: a signal transmission unit for generating a MIMO signal including a plurality of pulse signals, and radiating the MIMO signal into space; a signal reception unit for receiving a reflection signal resulting from reflection, by a target, of the MIMO signal radiated from the signal transmission unit; a demodulation unit for demodulating the MIMO signal from the reflection signal received by the signal reception unit; a beam-forming unit for forming beams in a plurality of different directions, by multiplying the plurality of pulse signals included in the MIMO signal demodulated by the demodulation unit by a respective plurality of different weighting coefficients; a control unit for changing noise power included in each of the beams in the plurality of directions formed by the beam-forming unit, by shifting a phase of the MIMO signal generated by the signal transmission unit and adjusting the plurality of weighting coefficients on the basis of an amount of phase shift of the phase; and a target detection unit for detecting the target from each of the beams in the plurality of directions formed by the beam-forming unit.

In one embodiment, a method includes receiving a first signal associated with a first multipath effect from a first radar installed on a vehicle at a first height, receiving a second signal associated with a second multipath effect from a second radar installed on the vehicle at a second height, wherein the first height and the second height are different, wherein a difference between the first height and the second height is configured to generate a mitigation of the first multipath effect and the second multipath effect, and wherein the first radar and the second radar have an overlapping field of view, and determining that a target exists in the overlapping field of view based on the first signal and the second signal.

A radar system and method are provided for reducing multipath interference signals. The multipath interference signals can be reduced by the radar system emitting electromagnetic waves that creates a null in the direction of expected multipath interference signals, such that the multipath interference signals are void (or substantially void) from signals received by the radar system.