Patent ID: 6600795
Filing Date: 2003-07-29
Classification: H03D,H03F,H04B,Y02D

Abstract:
A receiving circuit comprising:first and second frequency converting circuits for accepting a received signal obtained through an antenna; a local frequency signal generating circuit coupled to said first and second frequency converting circuits for generating middle frequencies between a radio carrier frequency of said received signal and radio carrier frequencies of adjacent upside and downside channels and further for outputting the upside frequency of the upside and downside two wave frequencies as a conversion frequency input to said first frequency converting circuit and for outputting the downside frequency thereof as a conversion frequency input to said second frequency converting circuit; a common wave extracting circuit coupled to said first and second frequency converting circuits for extracting a component present in common in both outputs of said first and second frequency converting circuits; a frequency offset circuit coupled to said common wave extracting circuit for removing a frequency offset remaining in an output of said common wave extracting circuit; and a filter coupled to said frequency offset circuit for removing an unnecessary frequency component remaining in an output of said frequency offset circuit.