A GPR system the implements a modified multistatic mode of operation is provided. The GPR is suitable for mounting on an unmanned aerial vehicle. The GPR system has radar transceivers. The GPR system transmits transmit signal serially via the transceivers. For each transceiver that transmits a transmit signal, the GPR system receives a return signal acquired by each transceiver except for a return signal for the transceiver that transmits the transmit signal. The GPR system outputs of matrix of return signals that includes a null value for the return signals of the transceivers that transmit.

Apparatus and methods are provided for using a retroflected target for calibrating environmental geometric sensing systems. In particular, apparatus and methods are provided for unstructured calibrations using a plurality of spatial sensing data acquisitions and the data correlations thereof. In various implementations, a combined LiDAR-RADAR detector is used to associate one with the other. According to one aspect of the present disclosure, a predetermined LiDAR detector is used as a reference frame for RADAR segmentation. Specifically, a LiDAR point-of-interest is conveyed to RADAR system for unstructured calibration. To that end, RADAR and LiDAR can be calibrated with one another without the need for absolute positioning.

To track an object with radar, and achieve greater than range resolution precision, the phase of a difference signal can be utilized and adjusted as the tracked object crosses between resolution ranges. Changes in the object's distance can be detected with greater than range resolution precision by utilizing the phase. Such changes can iteratively inform the determined distance across multiple phase cycles within a single distance range. As the movement of the object approaches, and then crosses, between resolution ranges, the phase as determined within an origin resolution range can be compared with a coincident phase within the destination resolution range and the difference can then be utilized to adjust the phase as the object then remains within the destination resolution range. Such phase adjustments can be applied across multiple resolution ranges, allowing for the tracking of an object, utilizing radar, while achieving greater than range resolution precision.

A method and a radar target simulator for generating a simulated radar echo signal. A radar signal is sent with known bandwidth from a radar sensor to be tested. The radar signal is received in the radar target simulator. The radar signal is filtered via a low-pass filter with known filter curve. The frequency spectrum of the filtered radar signal over the full bandwidth of the low-pass filter is determined. A corrected frequency spectrum and the power of a radar signal corresponding to the corrected frequency spectrum are calculated. A scaled radar signal from the filtered radar signal and the radar echo signal as a reflection of the scaled radar signal are calculated. The radar echo signal is sent from a transmitting antenna of the radar target simulator to the radar sensor to be tested.

The present invention relates to the technical field of automobile maintenance and device calibration, and discloses a bracket apparatus, the bracket apparatus including a base, a vertical rod, and a sliding assembly. The base supports the vertical rod, the vertical rod being vertically disposed and one end thereof being mounted to the base; and the sliding assembly is movably mounted to the vertical rod and may slide along the vertical rod, and the sliding assembly is configured to carry a required calibration apparatus. In the bracket apparatus of the present invention, the sliding assembly may slide along the vertical rod, and a height of the calibration apparatus carried by the sliding assembly may be adjusted as required to meet different height requirements of different calibration apparatuses, so that the bracket apparatus may carry different calibration apparatuses for use.

A transponder, able to equip a cooperative target facing a Doppler radar, includes at least one receiving antenna able to receive a signal transmitted by said radar and a transmitting antenna able to retransmit a signal. The signal received by the receiving antenna is amplitude-modulated before being retransmitted by the transmitting antenna to produce a variation of the radar cross-section of the target, the variation triggering a frequency shift between the signal transmitted and the signal received by the radar comparable to a Doppler echo. The transponder applies notably to the field of radars, more particularly for collaborative systems also operating at low velocity or nil velocity. It applies for example to assisted take-off, landing and deck-landing of drones, in particular rotary-wing drones, as well as manned helicopters.

This invention relates in general to the field of safety devices, and more particularly, but not by way of limitation, to systems and methods for providing advanced warning and risk evasion when hazardous conditions exist. In one embodiment, a vicinity monitoring unit is provided for monitoring, for example, oncoming traffic near a construction zone. In some embodiments, the vicinity monitoring unit may be mounted onto a construction vehicle to monitor nearby traffic and send a warning signal if hazardous conditions exist. In some embodiments, personnel tracking units may be worn by construction workers and the personnel tracking units may be in communication with the vicinity monitoring unit. In some embodiments, a base station is provided for monitoring activities taking place in or near a construction site including monitoring the locations of various personnel and vehicles within the construction site.

An RCS reduction surface for reducing a radar cross section of an object is described. The RCS reduction surface comprises at least one absorber portion, wherein the absorber portion is configured to absorb radar waves. The RCS reduction surface further comprises at least one reflecting portion, wherein the reflecting portion is configured to reflect radar waves. A first plane being associated with a top surface of the absorber portion and a second plane being associated with a top surface of the reflecting portion are spaced from each other by a predefined distance. The predefined distance is configured such that radar waves with a predefined wavelength range that are reflected at the absorber portion and at the surface of the reflecting portion interfere destructively with each other. Further, an RCS reduction member and a radar test system are described

Radar testing systems with radar system rotational systems and methods for using the radar testing systems are disclosed. A radar testing system includes a radar system to be tested, a computer, and a radar simulator. A radar sensor rotation system mechanically coupled to a radar sensor of the radar system is communicatively coupled to the computer and configured to rotate the radar sensor to predefined and desired angles for predetermined amounts of time during testing of the radar system.

A method of determining an alignment error of an antenna is described, wherein the antenna is installed at a vehicle and in cooperation with a detection device, and wherein the detection device is configured to determine a plurality of detections. Determining the plurality of detections comprises emitting a first portion of electromagnetic radiation through the antenna, receiving a second portion of electromagnetic radiation through the antenna, and evaluating the second portion of electromagnetic radiation in dependence of the first portion of electromagnetic radiation in order to localize areas of reflection of the first portion of electromagnetic radiation in the vicinity of the antenna. The method comprises determining a first detection and at least a second detection by using the detection device, and determining the alignment error by means of a joint evaluation of the first detection and the second detection.