| 摘要 |
PURPOSE:To increase the degree of frequency stability for a mobile station, by transmitting a signal of highly stable reference frequency from a base station and setting the reference frequency of a phase locking circuit at the mobile station with the signal obtained by dividing the signal of the reference frequency. CONSTITUTION:The 1st communication system comprises a base station B1 and mobile stations C11-C13; and the 2nd communication system includes a base station B2 and mobile stations C21-C23. A base station B3 which does not form any communication system always transmits the signal of standard frequency (different from the frequencies used at stations B1 and B2). The mobile station receives the signal of reference frequency from the station B3 and then divides the frequency of the signal to use it to the reference frequency of a phase locking circuit (including a phase comparator, a low pass filter and a voltage control oscillator). The phase locking circuit produces the transmitting/receiving frequency signal for call. |
