| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a stepped transmission power control circuit capable of holding the phase jump quantity of one control at a small value and preventing its characteristics from being deteriorated. SOLUTION: A transmission power controlling up-down counter 101 inputs a transmission power control bit(TPC bit) from a base station in a closed loop control state and outputs gain indicated by the TPC bit from its count output terminal as a count output consisting of conventional output bits corresponding to 1/2<n> of a conventional control variable and n bits at control timing inputted from a 2<n> pulses generation circuit 104 and faster than conventional timing by 2<n> times. A gain control circuit 12 converts the count output to control voltage and a gain variable amplifier 103 changes the gain, based on the control voltage, amplifies a signal to be sent to the base station by the changed gain and transfers the amplified signal to the succeeding power amplification part. Since control steps and a control variable are minutely divided, the phase jump quantity of one control can be reduced.</p> |
