Radar device

Abstract

A radar device is mounted on a vehicle, for detecting an object, and includes: a transmitting unit for transmitting an electromagnetic wave as a transmitter signal; a receiving unit for receiving a reflected signal that is reflected from the object as a receiver signal; a signal processing unit for measuring a distance and a relative velocity between the vehicle and the object on the basis of a beat signal that is obtained by the transmitter signal and the receiver signal; and an interference detecting unit for detecting the interference signal from another radar device or a communication device on the basis of a signal intensity of the frequency range that is not used for measuring the distance to the object and the relative velocity of the object.

1 . A radar device, which is mounted on a vehicle for detecting an object, comprising:
 transmitting means for transmitting an electromagnetic wave as a transmitter signal;   receiving means for receiving a reflected signal that is reflected from the object as a receiver signal;   signal processing means for measuring a distance and a relative velocity between the vehicle and the object on the basis of a beat signal that is obtained by the transmitter signal and the receiver signal; and   interference detecting means for dividing frequencies that are obtained by frequency analysis of the signal processing means into a frequency range that is used for measuring the distance to the object and the relative velocity of the object and a frequency range that is not used for measuring the distance to the object and the relative velocity of the object to detect an interference signal from one of another radar device and a communication device on the basis of a signal intensity within the frequency range that is not used for measuring the distance to the object and the relative velocity of the object.   
   
   
       2 . The radar device according to  claim 1 ,
 wherein a radar system is an FM-pulse Doppler system, and   wherein the interference detecting means monitors whether the signal intensity within the frequency range that is not used for measuring the distance to the object and the relative velocity of the object of all range gates exceeds a threshold value or not, to detect the interference signal from the one of the another radar device and the communication device.   
   
   
       3 . The radar device according to  claim 1 ,
 wherein a radar system is an FM - pulse Doppler system, and   wherein the interference detecting means monitors whether the signal intensity within the frequency range that is not used for measuring the distance to the object and the relative velocity of the object of a plurality of range gates of a given rate or more exceeds a threshold value or not, to detect the interference signal from the one of the another radar device and the communication device.   
   
   
       4 . The radar device according to  claim 1 ,
 wherein a radar system is an FM - pulse Doppler system, and   wherein the interference detecting means monitors whether the signal intensity within the frequency range that is not used for measuring the distance to the object and the relative velocity of the object of a predetermined of range gate exceeds a threshold value or not, to detect the interference signal from the one of the another radar device the communication device.   
   
   
       5 . The radar device according to  claim 1 ,
 wherein a radar system is an FM-pulse Doppler system, and   wherein the interference detecting means monitors whether the signal intensity within the frequency range that is not used for measuring the distance to the object and the relative velocity of the object of a range gate for measuring a longest distance exceeds a threshold value or not, to detect the interference signal from the one of the another radar device and the communication device.   
   
   
       6 . The radar device according to  claim 1 ,
 wherein a radar system is an FM-pulse Doppler system, and   wherein the interference detecting means monitors whether the signal intensity within the frequency range that is not used for measuring the distance to the object and the relative velocity of the object of a range gate  0  for measuring a shortest distance exceeds a threshold value or not, to detect the interference signal from the one of the another radar device and the communication device.   
   
   
       7 . The radar device according to  claim 1 , wherein the interference detecting means monitors whether the signal intensity within the frequency range that is not used for measuring the distance to the object and the relative velocity of the object in all beam directions at a time of antenna scanning exceeds a threshold value or not, and a measurement of the distance to the object and the relative velocity of the object in the beam directions is prevented when detecting the interference signal that exceeds the threshold value from the another radar device and the communication device in a given beam direction. 
   
   
       8 . The radar device according to  claim 1 , wherein the interference detecting means monitors whether the signal intensity within the frequency range that is not used for measuring the distance to the object and the relative velocity of the object in all beam directions at a time of antenna scanning exceeds a threshold value or not, and a measurement of the distance to the object and the relative velocity of the object in the beam directions is performed by using past measured values of the distance and the relative velocity when detecting the interference signal that exceeds the threshold value from the another radar device and the communication device in a given beam direction. 
   
   
       9 . The radar device according to  claim 1 , wherein the interference detecting means monitors whether the signal intensity within the frequency range that is not used for measuring the distance to the object and the relative velocity of the object in all beam directions at a time of antenna scanning exceeds a threshold value or not, and a measurement of the distance to the object and the relative velocity of the object in the beam directions is performed only on a spectrum which exceeds the threshold value when detecting the interference signal that exceeds the threshold value from the another radar device and the communication device in a given beam direction.