摘要:
A field disturbance sensor (82) operates with relatively low power, provides an adjustable operating range (83), is not hypersensitive at close range, and allows co-location of multiple sensors. The sensor includes a transmitter that transmits a sequence of transmitted bursts (90) of electromagnetic energy. The sequence of bursts has a burst repetition rate, and each burst has a burst width and comprises a number of cycles at a transmitter frequency. The sensor includes a receiver which receives electromagnetic energy at the transmitter frequency, and includes a mixer which mixes a transmitted burst with reflections of the same transmitted burst to produce an intermediate frequency signal. The mixer mixes the transmitted burst with reflections of the transmitted burst, the burst width defines the sensor range. The burst repetition rate is randomly or pseudorandomly modulated so that bursts have a phase which varies. A second range-defining mode transmits two radio frequency bursts, where the time spacing between the bursts defines the maximum range divided by two.
摘要:
A vehicular collision avoidance radar system using digital signal processing techniques including a transmit section (202) that generates a two channel transmit frequency. An antenna (210) both transmits the transmit signal and receives a reflected receive signal. A Schottky diode mixer (208) generates a difference signal having a frequency equal to the transmit frequency minus the receive frequency. A signal switch (304) in a front end electronics section (300) time demultiplexes and samples the channel 1 and channel 2 signals. The samples are coupled to a two-channel analog to digital (A/D) converter (310). A digital electronics section (500) receives the digital information and performs a Fast Fourier Transform (FFT) on each channel of digital data to determine relative speed and range of a target based upon the frequency and the difference in phase of the two channels. The digital electronics section also receives information regarding the status of vehicle operation and/or controls to determine the degree of danger presented by an identified target.
摘要:
La présente invention concerne un dispositif de réduction de bruit dans un récepteur radar. Le bruit à réduire étant en 1/F k et le radar effectuant une codification de l'émission selon au moins deux fréquences (F 1 , F 2 ), le dispositif comporte au moins :
des moyens (22) d'aiguillage des signaux reçus sur au moins deux voies (210, 211) de telle sorte que, lorsqu'une cible est illuminée par une émission à la première fréquence de code (F 1 ) le signal reçu correspondant (S 1 ) soit échantillonné et aiguillé sur une première voie (210) puis, lorsque la cible est illuminée par la deuxième fréquence de code (F 2 ) le signal reçu correspondant (S 2 ) soit échantillonné et aiguillé sur une deuxième voie (211) ; des moyens (25,71) de combinaison linéaire du signal (S 1 ) présent sur la deuxième voie (210) et du signal (S 2 ) présent sur la deuxième voie (211), la combinaison linéaire synthétisant un filtrage du bruit.
摘要:
A method and apparatus for evaluating a driver's performance under actual real-time conditions to determine the driver's ability to safely operate a vehicle, utilizes the information that is gathered by a radar system (200, 210) and other sensors (4a), together with information previously stored in an event recording device (5). Conditions monitored are used to make a determination as to whether the driver is performing in conformity with normal driving standards and the driver's own past performance. The driver's performance is constantly monitored and compared to that driver's past performance to determine whether the driver's present performance is impaired, and if so, whether the impairment is detrimental to the driver's ability to safely operate the vehicle.
摘要:
Die Erfindung bezieht sich auf einen Radar-Höhenmesser der nach dem FMCW-Prinzip aufgbaut ist und im C-Band arbeitet.Hierzu wird vorgeschlagen, das Gerät in MMIC-Technik mit vollständig digitaler Auswertung und Modekontrolle zu konzipieren, wobei die digitale Auswertung die Erzeugung einer Wellenform des Senders erlaubt, die die Eigenschaften : - Silent mode während der Verarbeitung - Stabilisierung der Sendefrequenz - Dopplerkompensation und - Diskriminierung von Falschzielen aufweist. Eine Ausführungsform mit Selbsttesteinrichtung ist beschrieben und in Aufbau und Funktion durch die Figuren der Zeichnung ergänzend erläutert.
摘要:
A range detection apparatus comprising a transmitter (4) adapted to transmit a microwave signal and a receiver (4) adapted to receive an echo signal reflected from a target which corresponds to a portion of the transmitted signal; a signal generating means (2) adapted to generate a drive signal to be applied to the transmitter (4) to produce the transmitted signal, the signal generator (2) producing a drive signal which includes a first signal frame (300a) comprising at least two frequencies and a second signal frame (301a) comprising at least two frequencies, the second signal frame (301a) differing from the first (300a), and a processor (11) adapted to process the echo signal together with the transmitted signal so as to determine the distance to the target that produced the echo signal. The apparatus is particularly suited for Frequency Shift Key (FSK) radar in automotive, typically adaptive cruise control functions. It may reduce ambiguities in range measurements. An equivalent method of reducing ambiguity is also disclosed.