| 摘要 |
<p>PROBLEM TO BE SOLVED: To avoid interference due to a high frequency signal between a transmission circuit and a reception circuit and between a plurality of oscillation circuits in the transmission reception circuit module, where the transmission circuit and the reception circuit are placed on one printed circuit board. SOLUTION: A transmission signal input terminal 27 and a reception signal output terminal 26 are placed on one end of a printed circuit board, a transmission reception common antenna terminal 12 is placed on the other end on the printed circuit board, a phase-locked loop circuit 20 is placed nearly in the middle of the printed circuit board, a transmission circuit and a reception circuit are placed to both sides on the printed circuit board with the phase-locked loop circuit 20 inbetween separately, and a transmission high frequency signal generating section 28, a 1st frequency conversion section 14, a 1st local frequency oscillation section 18, and a 2nd frequency conversion section 22 are placed and isolated electromagnetically by electromagnetic shield plates 41, 42, 43, 44.</p> |
