Patent ID: 8223902
Filing Date: 2012-07-17
Classification: H03D,H04B,H04L

Abstract:
1. A complex signal processing circuit for processing an analog complex signal including an in-phase signal and a quadrature signal, comprising: an analog complex filter configured to combine the in-phase signal with the quadrature signal and output the resultant signal as a first analog signal, and combine the quadrature signal with the in-phase signal and output the resultant signal as a second analog signal, to attenuate an image component contained in the analog complex signal; an analog-to-digital converter configured to convert the first and second analog signals into first and second digital signals, respectively; a first digital complex filter configured to apply a complex operation to the first and second digital signals to attenuate a component corresponding to the quadrature signal of the first digital signal and output the resultant signal as a third digital signal, and attenuate a component corresponding to the in-phase signal of the second digital signal and output the resultant signal as a fourth digital signal; a digital bandwidth limited filter configured to apply a complex operation to the third and fourth digital signals to allow a target component and an image component of a digital complex signal including the third and fourth digital signals to pass therethrough, and attenuate an adjacent interference component adjacent to the target component on a frequency axis, and output the resultant signals as fifth and sixth digital signals; and an IQ imbalance correction circuit configured to correct a quadrature error and an amplitude error between the fifth and sixth digital signals.