Patent ID: 8787859

Claim:
An automatic gain control apparatus for a wireless receiver, comprising: a plurality of variable gain amplifiers, one variable gain amplifier provided for each one of a plurality of receive chains; and a gain controller to control a gain of the variable gain amplifiers provided for the plurality of receive chains, the gain controller comprising: a plurality of output level measurement units, each output level measurement unit to measure an output level of a corresponding receive chain; a common gain determination unit to determine a common gain for each of the variable gain amplifiers based on a statistical value obtained from the output levels measured by the plurality of output level measurement units; a gain setting unit to set a gain to each of the variable gain amplifiers; and a plurality of adjusted gain determination units, each adjusted gain determination unit determining an adjusted gain independently for each variable gain amplifier within a range narrower than the range of the common gain based on an output level of a corresponding receive chain measured after the gain setting unit sets the common gain to each one of the variable gain amplifiers of the corresponding receive chains, wherein the gain setting unit sets a gain to each of the variable gain amplifiers based on the common gain and the adjusted gain.