| 摘要 |
<p>PURPOSE:To accurately correct a carrier drift and to improve the transmission characteristic within and at the outside of the pass band by providing a frequency detecting means with simple constitution capable of highly accurate frequency measurement to a receiver of a base station or a mobile station so as to apply highly accurate automatic frequency adjustment singly in the mobile station or between the base station and the mobile station. CONSTITUTION:A transmission wave F1 in the base station is converted into an intermediate frequency by a reciever 4.5. Frequency measuring sections 3.8 measure the frequency, but since the frequency of transmission wave at the base station is accurate, the difference between the measured frequency and the intermediate frequency is due to the frequency error in a temperature compensation type crystal oscillator (TCX) 4.7. A TCXO control section 4.9 calculates the frequency change corresponding to the frequency error to control a TCXO 4.7 in a way cancelling the frequency error thereby calibrating the received frequency into the transmission frequency F1 of the base station. On the other hand, since the reference frequency source of a transmitter of the mobile equipment is used normally in common with the receiver, the transmission frequency is calibrated into the reception frequency F2 of the base station.</p> |
