Level control method for amplifier repeater for mobile radio systems

摘要

The amplifier repeater circuit has the HF signal (E) fed to the amplifier (1) via a regulating stage. The amplifier output is fed to a mixer (13), a low pass filter (15), a rectifier (17) and a automatic gain controller (AGC) (19). The AGC compares the demodulated signal with an applied reference (23), that represents the permissible total power of the intermodulation product, in the transmission range. The AGC output is used to control the regulator, in dependence on the intermodulation product of the demodulated output.