| 摘要 |
PURPOSE:To curtail a local oscillator requiring high stability by generating a carrier wave for intermediate frequency band modulation and the carrier wave for radio frequency conversion by a PLL circuit on the basis of an inputted clock. CONSTITUTION:In a transmitting system, the carrier wave fMOD for intermediate frequency band modulation at the time of modulation by a modulator (MOD) 1 based on the inputted clock is generated by the PLL circuit 5 on the basis of the clock. Besides, the carrier wave fTX for radio frequency conversion to be used at the time of the conversion of an output signal from the modulator 1 into radio frequency by a transmitter (TX) 2 is generated by the PLL circuit 6 on the basis of this clock as well. Further in a receiving system to input a received signal from the transmitting system, the carrier wave fRX for intermediate frequency band conversion and an intermediate frequency band carrier wave fDEM for demodulation are generated by the PLL circuits 7, 8 on the basis of the clock synchronized with the transmitting system. |
