| 摘要 |
<P>PROBLEM TO BE SOLVED: To solve the problem caused by distortion of an amplitude modulation wave outputted from a controller (interrogator). <P>SOLUTION: On the interrogator 10, a first oscillator 13 and a second oscillator 15 for outputting a first signal and a second signal left by a predetermined frequency for constituting a question signal respectively; a power synthesis circuit 16 for synthesizing the first signal and the second signal; and an antenna 11 bonded to a synthesis output end of the power synthesis circuit 16 are provided. On a transponder 1, a second mixer means 3 for mixing the first signal and the second signal and outputting a signal of difference of these frequencies is provided. The synthesized first signal and second signal are transmitted during transmission period. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
