DEVICE FOR CONTROLLING POWER LEVEL IN FA OF RADIO FREQUENCY RECEIVING DEVICE OF CODE DIVISION MULTIPLE ACCESS MOBILE COMMUNICATION BASE STATION SYSTEM

摘要

PURPOSE: A device for controlling a power level in FA(Frequency Allocation) of an RF(Radio Frequency) receiving device of a CDMA(Code Division Multiple Access) mobile communication base station system is provided to detect power level differences by each FA(Frequency Allocation) to lower a power level of FA having relatively high power level and perform AGC(Auto Gain Control) for 3FA signals. CONSTITUTION: An analog down converter(60) down-converts RF(Radio Frequency) signals outputted from a receiving unit into IF(Intermediate Frequency) signals for multi-FA(Frequency Allocation). A digital down converter(70) converts the down-converted IF signals for the multi FA into digital IF signals, and down-converts digital IF signals for the multi FA into baseband signals for I/Q channels by each FA, for outputting to channel cards(50,51,52) corresponding to each FA. An IF analog controller(120) decides the degree of power level differences between each FA by using power level values for the down-converted baseband signals of each FA, and selects one FA generating a large power level difference in FA. And the IF analog controller(120) supplies an attenuation control signal for attenuating power for the selected FA. An IF analog processor(90) attenuates power of corresponding FA having a large power level according to the attenuation control signal from the IF analog controller(120), and adds every IF signal for each FA to output IF signals for 3FA. An AGC(Auto Gain Control) unit(130) performs the AGC for the added signals of the 3FA outputted by being attenuation-controlled in the IF analog processor(90) according to a supplied AGC signal.