APPATURUS AND METHOD FOR AUTOMATIC GAIN CONTROL IN BROADBAND WIRELESS ACCESS COMMUNICATION SYSTEM

摘要

An apparatus and a method for AGC(Automatic Gain Control) in a BWA(Broadband Wireless Access) communication system and a method thereof are provided to measure the characteristic difference of signals between a non-beam formation period and a beam formation period and perform gain control for a signal of a beam formation period by using frame structure information transmitted through the initial data symbol of a frame. An apparatus for AGC in a BWA communication system comprises a map analysis part(616), a symbol power calculation part(614), a beam formation gain calculation part(615), an energy detection part(611) and an AGC part(620). The map analysis part(616) analyzes an Rx signal and judges a beam formation period. The symbol power calculation part(614) measures the average signal level of every symbol from the Rx signal. The beam formation gain calculation part(615) calculates the power difference between a signal of a non-beam formation period and a signal of a beam formation period, based on the judged beam formation period information and the measured average signal level information. The energy detection part(611) measures the average signal level of preamble symbol signals before an FFT(Fast Fourier Transform) operation is performed for the Rx signal. The AGC part(620) adds the average preamble signal level to the power difference, obtains the difference between the added value and a reference power value as a gain control value, and provides it to an IF amplifier(606).