A constant false alarm rate (CFAR) device for a signal detection system is disclosed herein. The CFAR device includes a first signal selection unit and a second signal selection unit. The first signal selection unit receives a last signal of a lagging sorting array and signals of one or more lagging guard cells, selects any one of the last signal of the lagging sorting array and the signals of the one or more lagging guard cell as a test signal based on a received guard cell size, and outputs the test signal. The second signal selection unit receives the test signal and signals of one or more leading guard cells, selects any one of the test signal and the signals of the one or more leading guard cells based on the guard cell size, and transfers this selected signal to the leading sorting array.

The present invention relates to the field of vehicle calibration and discloses a calibration system and a calibration bracket. The calibration bracket includes a base, a stand assembly and a beam assembly. The stand assembly includes a first upright rod and a second upright rod. One end of the first upright rod is detachably mounted on the base. The second upright rod is connected to the first upright rod. The first upright rod is nested or folded with the second upright rod to reduce the length of the stand assembly. The beam assembly is supported by the stand assembly. In the calibration bracket of the present invention, the first upright rod is detachably mounted to the base so that the base detaches from the first upright rod, thereby facilitating loading and handling of the calibration bracket. In addition, the first upright rod is adapted to be nested or folded with the second upright rod, which can reduce the length of the stand assembly and further facilitate the loading and handling of the calibration bracket.

Distance detection method and device are provided. The distance detection method comprises: providing a directional signal emitting module; providing a directional signal receiving module having a constant bandwidth; providing a distance detection signal to the directional signal emitting module; changing a frequency of the distance detection signal provided to the directional signal emitting module, and judging whether the directional signal receiving module can decode a reflected directional signal into a received signal; and judging a distance between an external object and the directional signal receiving module according to whether the received signal corresponding to the frequency of the distance detection signal can be decoded.

A method of operating electro-acoustical transducers such as PMUTs involves applying to the transducer an excitation signal over an excitation interval, acquiring at the transducer a ring-down signal indicative of the ring-down behavior of the transducer after the end of the excitation interval, and calculating, as a function of said ring-down signal, a resonance frequency of the electro-acoustical transducer. A bias voltage of the electro-acoustical transducer can be controlled as a function of the resonance frequency. An acoustical signal received can be transduced into an electrical reception signal and a damping parameter of the electro-acoustical transducer can be calculated as a function of the ring-down signal so that a cross-correlation reference signal can be synthesized as a function of the resonance frequency and the damping ratio of the electro-acoustical transducer. Such a cross-correlation reference signal can be used for cross-correlation with the electrical reception signal to improve the reception quality.

A method for calibrating a radar sensor of a vehicle includes fixing the vehicle in place on a transport; moving the vehicle along a route past a reflector for radar waves using the transport; irradiating the reflector with radar waves and receiving reflected radar waves using the radar sensor while the vehicle is moved along the route; determining a position and/or an alignment of the radar sensor relative to the reflector multiple times based on the reflected radar waves; and spatially calibrating the radar sensor based on the ascertained positions and alignments relative to the reflector by ascertaining a position and/or an alignment of the radar sensor relative to the vehicle.

A lateral distance sensor diagnosis apparatus cooperating with a lateral distance sensor in a vehicle includes a travel enabled distance acquisition section and a diagnosis test section. The travel enabled distance acquisition section determines whether the vehicle is estimated to have contact with an object detected by the lateral distance sensor, based on a distance detected by the lateral distance sensor and a present steering angle. When determining that the vehicle is estimated to have contact with the detected object, the travel enabled distance acquisition section acquires a travel enabled distance based on a distance detected by the lateral distance sensor. The diagnosis test section determines that the lateral distance sensor fails to operate normally when a movement distance becomes greater than the travel enabled distance under state where the steering angle is an angle causing the vehicle to have contact with an object detected by the lateral distance sensor.

The present disclosure provides a method and system for processing an obstacle detection result of an ultrasonic sensor array. The method comprises: obtaining obstacle coordinates collected by ultrasonic sensors in an ultrasonic sensor array; inputting the obstacle coordinates collected by ultrasonic sensors in the ultrasonic sensor array into a pre-trained neural network model, to obtain true or false labels for the obstacle coordinates collected by the ultrasonic sensors output by the pre-trained neural network model; process the obstacle coordinates collected by the ultrasonic sensors in the ultrasonic sensor array according to the true or false labels. The present disclosure improves the accuracy in the obstacle detection of the ultrasonic sensor array, avoids detection error and omission and improves the driving safety.

An object detection apparatus detects an object in a vicinity of a moving body in a state of being mounted to the moving body. The object detection apparatus measures a reverberation frequency that is a frequency of a reverberation signal that is generated in a transceiver that externally transmits a transmission wave that is an ultrasonic wave and receives a reception wave that includes a reflected wave of the transmission wave from the object. The object detection apparatus detects a specific segment that is an occurrence segment in which occurrence of beat that is attributed to a plurality of reverberation frequency components is confirmed in the reverberation signal, or a non-occurrence segment in which the occurrence of beat does not significantly occur. The object detection apparatus sets a measurement segment in which the reverberation frequency is measured in the non-occurrence segment based on a detection result of the specific segment.

A stone dumping real time measuring system for a stone dumping vessel includes a boom. The boom is mounted to a control cabin of the stone dumping vessel and can extend outwardly from the control cabin to be located above a predetermined stone dumping position. A signal line hangs from the boom. A floater is connected to the other end of the signal line. The floater is provided with a positioning device, a surge compensator, and a depth sounder. The floater freely floats on the water through the separate design of the floater and the stone dumping vessel. The floater is directly positioned by the positioning device of the floater, and the surge compensator is able to correct a measurement error of the depth sounder to instantly report the stone dumping result and to improve the accuracy and precision of the stone real time measuring system.

A vehicle flow monitoring system for detecting both a car count and direction of movement of vehicles passing a point of interest. The vehicle flow monitoring system generally includes a car counter which may include a microcontroller and a pair of distance sensors. Each of the distance sensors is oriented toward a unique point of interest. Each of the distance sensors includes a threshold distance reading which is used to detect whether a vehicle has passed underneath the car counter. The system may determine direction of travel of the vehicle based on which of the distance sensors is passed by the vehicle first. The microcontroller may assign an Event ID to each time a vehicle passes each of the sensors, with the Event ID being used to identify when and if the vehicle should be counted, or whether a non-vehicle object has passed the car counter.