| 摘要 |
PROBLEM TO BE SOLVED: To provide a transmitter/receiver for a millimeter-wave band and a microwave band, that simplifies circuit configuration and reduces the number of the components for attaining compact size and weight reduction at a low cost, and to provide a radar and a communication unit. SOLUTION: An oscillator 1 is connected to a 1st port #1 of a 4-port circulator 6, an antenna 8 is connected to a 2nd port #2, a mixer 9 is connected to a 3rd port #3 facing the 1st port #1, and a matched termination 7 terminates a 4th port #4. The oscillator 1 partly gives its oscillation signal to the mixer 9, by its cross-coupling, from the 1st port #1 of the circulator 6 to the 3rd port #3 as a local signal. Thus, the need for an isolator at the post-stage of the oscillator 1 and a coupler to extract the local signal is eliminated. |
