| 摘要 |
PURPOSE:To obtain a smooth communication operation by providing a carrier recovery means and a recovered carrier latch means so as to apply spread modulation to a recovered carrier thereby generating a transmission signal and reducing a time for carrier recovery. CONSTITUTION:A control voltage to a VCO 12 is held by using a hold circuit 27 in a carrier recovery section A'. An output of the VCO 12 oscillated by the holding voltage is fed to a mixer 22 of a transmission section. That is, the hold circuit 27 holds a control voltage of the VCO 12 based on the recovered carrier when the reception state is switched to the transmission state even without the presence of a reception carrier and the recovered carrier is used for the transmission and a mobile station MS is subject to subordinate synchronization to a base station BS. Thus, frequency locking and phase locking are implemented at a high speed and the time for carrier recovery is reduced to attain smooth communication. |
