Patent ID: 6560447
Filing Date: 2003-05-06
Classification: H03D,H04B,H04L

Abstract:
A receiver for receiving and processing a radio frequency signal using a DC offset correction scheme within a radio communication system, the receiver comprising:a receiver antenna for receiving the radio frequency signal; a radio frequency frontend coupled to the receiver antenna, the radio frequency frontend comprising: a receiver radio frequency amplifier for selecting a desired portion within a band of frequencies of the radio frequency signal, and for amplifying the desired portion, thereby generating a desired signal, a receiver local oscillator for generating a local oscillator signal, a receiver radio frequency mixer coupled to the output of the RE amplifier and coupled to the output of the local oscillator for converting the desired signal to a baseband signal using the local oscillator signal, and a receiver intermediate frequency amplifier coupled to the output of the radio frequency mixer for providing a programmable intermediate frequency gain to amplify the baseband signal, thereby generating an intermediate frequency amplifier output; and a baseband backend coupled to the radio frequency frontend, the baseband backend comprising: an anti-aliasing filter for receiving the intermediate frequency amplifier output and for attenuating a plurality of frequency bands, thereby generating an anti-aliasing filter output, an analog to digital converter coupled to the output of the anti-aliasing filter for converting the anti-aliasing filter output from an analog format to a digital format, thereby generating a digital signal, a DC offset correction circuit coupled to the output of the analog to digital converter for receiving the digital signal and for calculating the average DC offset and correcting it, thereby generating a first offset correction signal and a second offset correction signal, and a digital to analog converter coupled to the output of the DC offset correction circuit for conversion of the first offset correction signal to analog form, thereby generating an analog signal, wherein the analog signal is used to DC bias the output of the receiver intermediate frequency amplifier.