| 摘要 |
PROBLEM TO BE SOLVED: To perform a stable operation of a PLL circuit even while reducing the number of parts. SOLUTION: A comparison frequency (b) outputted from a frequency divider 2 is controlled so as to be X times as long as a channel interval dF by making the frequency-diving number R in the frequency divider 2 to be R=a/(dF×X) (X is a natural number) and also making the denominator of the frequency diving number to be X in a fraction frequency divider 8 at the time when a receiving station transmission frequency signal is generated in the case a reference frequency outputted from a reference oscillator 1 is defined as (a) and the channel interval is defined as dF, the comparison frequency (b) outputted from the frequency divider 2 is also controlled so as to be b=dF×X×(K+1)/K by making the frequency dividing number R in the frequency divider 2 to be R=a(K+1)/(dF×K×X) and also making the denominator of the frequency dividing number to be X in the fraction frequency divider 8 in the case the frequency dividing number is defined as K in a frequency divider 9 when a transmission carrier wave frequency signal is generated, and the current of a charge pump 4 is further controlled so as to be (K+1)K times as high as the current at the time when the receiving station transmission frequency signal is generated. |
