| 摘要 |
PURPOSE:To simplify the operation of unit and the constitution, by commonly using one local oscillator section for transmission and reception. CONSTITUTION:The local oscillator section 20 ascillates one frequency among fL+Nfc and feeds it to the transmission frequency conversion section 4 via the selector 23. Next, the fixed oscillator 21 oscillates the frequencies of (N+1)fc and the output is fed to the frequency converter 22, it is mixed with the output of the local oscillation section 20, the frequency of the local oscillation section 20 is shifted by (N+1)fc and fed to the reception frequency conversion section 12 via the selector 23. Accordingly, the frequency distance of the one channel transmission and reception system is separated by fc(N+1) by taking the number of channels as N. The relation of frequency between the transmission and the reception is possible for inversion with the selection of the operation of the selector 23. Further, when N is changed, it can simply be coped with by replacing the crystal chip of the oscillator 21. Thus, the operation of the unit can be simpler and the constitution of the entire unit can be simplified. |
