Patent ID: 7148840
Filing Date: 2006-12-12
Classification: G01S

Abstract:
1. A radar apparatus, comprising: a transmitter unit having a high-frequency oscillating unit whose oscillation frequency is variable, and a pulse amplitude modulating unit for amplitude-modulating a pulse of a transmission high-frequency signal output from said high-frequency oscillating unit with a first control pulse signal; a receiver unit having a gating unit for turning on and off an input of a reception high-frequency signal with a second control pulse signal; and a controlling unit for controlling said transmitter unit and said receiver unit, and for switching between a first operation mode for making the apparatus function as an FM-CW radar and a second operation mode for making the apparatus function as a pulse radar; and wherein: said receiver unit comprises a reception signal processing circuit having a first frequency converter for frequency-converting the reception high-frequency signal via the gating unit with an output of the high-frequency oscillating unit, a first band-pass filter provided on an output side of the first frequency converter, a second frequency converter for frequency-converting an output of the first band-pass filter with the first control pulse signal, and a second band-pass filter provided on an output side of the second frequency converter; and said controlling unit makes the apparatus function as the FM-CW radar by switching to an FM-CW modulation mode for outputting the transmission high-frequency signal as a continuous wave, which is frequency-modulated by inputting a triangular wave to the high-frequency oscillating unit, and by making the first control pulse signal of said transmitter unit and the second control pulse signal of said receiver unit inversely operate to alternately make a transmission of the transmitter high-frequency signal and a reception of the receiver high-frequency signal, in the first operation mode, and said controlling unit makes the apparatus function as the pulse radar by generating a short width pulse from the first control pulse signal and driving the pulse amplitude modulating unit, and by sliding the second control pulse signal of the receiver unit at a predetermined delay time interval from the first control pulse signal to gate the reception high-frequency signal, in the second operation mode.