Patent ID: 6771719
Filing Date: 2004-08-03
Classification: H03G

Abstract:
An automatic gain control system comprising:first amplifying means for amplifying an intermediate frequency signal; second amplifying means for amplifying an radio frequency signal received; signal level detecting means for detecting difference between a level of output signal of the first amplifying means and a predetermined level; first controlling means for controlling a gain of the first amplifying means; second controlling means for controlling a gain of the second amplifying means; and third controlling means for changing operation of the first controlling means and the second controlling means according to a first predetermined value and an output of the signal level detecting means, wherein the third controlling means comprises: counting means for reaching the first predetermined value successively; limiting means for an output of the signal level detecting means by an output level of the counting means; and, subtracting means for subtracting an output of the limiting means from an output of the signal level detecting means.