GAIN CONTROL METHOD, GAIN CONTROL CIRCUIT, AND MOBILE COMMUNICATION TERMINAL WHERE THE GAIN CONTROL CIRCUIT CAN BE UTILIZED

摘要

PROBLEM TO BE SOLVED: To provide an efficient gain control technology. SOLUTION: A power value acquisition section 102 of an automatic gain control section 100 calculates the value of the power of a received signal. A comparison section 104 compares the power value with a threshold value to classify the power value into a plurality of levels. A counter 108 accumulates evaluation values depending on the level of the power. A gain control voltage generating section 110 references a parameter table 112 to acquire a gain change value corresponding to the accumulated value and the next evaluation period, to give the control voltage to the amplifier and to set the next evaluation period. When the power value is greatly different from a target value, the evaluation period is shortened and when the power value is converged around the target, the evaluation period is prolonged.