AUTOMATIC GAIN ADJUSTMENT APPARATUS AND METHOD THEREOF, ESPECIALLY ADJUSTING GAIN WITH SIMPLE CONFIGURATION AND HIGH ACCURACY

摘要

PURPOSE: An automatic gain adjustment apparatus and a method thereof are provided to adjust gain with simple configuration and high accuracy. CONSTITUTION: The automatic gain adjustment apparatus of a feedback control system(5) controls a control target(8) based on an input signal and uses a phase difference between an output signal obtained from the control target and the input signal. A phase shift unit(40) is connected to an input port of the feedback control system, and shifts the phase of the input signal. The automatic gain adjustment apparatus sets the phase shift of the phase shift unit so that a frequency of the input signal supplied to a closed loop is equal to a cross frequency at which an open loop gain forming the feedback control system becomes 0 dB.