Patent ID: 7292169

Claim:
A receiving device comprising: a receiver receiving a radio signal; a frequency converter converting a frequency of an analog signal from the receiver; an A/D converter converting the analog signal into a digital signal; and a digital signal processor processing the digital signal to obtain received data, wherein the A/D converter includes: a variable gain amplifier adjusting a signal level of the analog signal; an A/D converting portion converting the analog signal from the variable gain amplifier into an m-bit digital signal and an n-bit (n>m) digital signal and outputting the m-bit digital signal and the n-bit digital signal, the n-bit digital signal serving as an output signal to the digital signal processor; and a gain controller calculating a coarse adjustment gain of the variable gain amplifier on the basis of a power of the m-bit digital signal to control the gain of the variable gain amplifier and calculating a fine adjustment gain on the basis of a power of the n-bit digital signal to control the gain of the variable gain amplifier.