Digital demodulation apparatus

摘要

A digital demodulation apparatus is provided for automatically controlling gain based on a state of receiving a digital modulated signal. The digital demodulation apparatus DSp amplifies a digital modulated signal wave Sb received through the air with the gain automatically controlled so as to have a predetermined amplitude. In the above apparatus DSp, a receive level variation detector 62 detects receive level variation D, C/N of the received digital signal wave Sb. A gain controller 15, Sac controls the gain based on the detected receive level variation D, C/N.