Patent ID: 8111188

Claim:
A radar system comprising a 3 dB coupler or a four-terminal device having functions equivalent thereto, and a pulse generator, a first terminal of said four-terminal device being supplied with an output signal from a transmitting and receiving high frequency oscillator; a second terminal of said four-terminal device being connected to a transmitting and receiving antenna, a third terminal and a fourth terminal of said four-terminal device being connected to two-state devices, respectively, each of the two-state devices being adapted to totally reflect a signal from said four-terminal device when it is impedance mismatched only for a predetermined period of time, and to direct the signal from said four-terminal device to a subsequent electronic circuit during the time period other than the predetermined period of time when it is impedance matched, said pulse generator being adapted to cause: said two-state device to be impedance mismatched at the time of transmission and said two-state device to be impedance matched at the time of reception.