Patent ID: 7817979

Claim:
A direct conversion RF receiver comprising: an RF antenna adapted to receive an RF signal; a preselect filter adapted to filter the incoming RF signal; a low noise amplifier adapted to amplify the received RF signal; a local oscillator producing a local oscillation signal having a frequency tuned to that of the received RF signal; a first RF mixer along an in-phase channel path adapted to multiply a received radio frequency signal with the local oscillation signal; a second RF mixer along a quadrature-phase channel path adapted to multiply the received radio frequency signal with a 90° phase-shifted version of the local oscillation signal; a first low pass filter filtering an output of the first mixer thereby outputting a downconverted in-phase signal I, centered at baseband; a second low pass filter filtering an output of the second mixer thereby outputting a downconverted quadrature phase signal Q centered at baseband; and a residual DC correction circuit adapted to perform a time derivative and subsequent integration of the I and Q signals, wherein the time derivative and subsequent integration are performed after analog-to-digital conversion and comprise solving one or more algebraic expressions.