Patent ID: 7180432
Filing Date: 2007-02-20
Classification: H03M

Abstract:
1. A complex sigma-delta modulation method, comprising: receiving an input signal; mixing the input signal with oscillator signals to produce a complex asymmetric input signal having a real component and an imaginary component; applying a first complex sigma-delta modulation process to the complex asymmetric input signal to produce a first sigma-delta modulated signal; applying a second complex sigma-delta modulation process to the first sigma-delta modulated signal to produce a second sigma-delta modulated signal, the first and second complex signal sigma-delta modulation processes each including real integration processes coupling the output signal of the second complex sigma-delta with the complex asymmetric input signal at the first complex sigma-delta modulated process; and conditioning the first and second sigma-delta modulated signals using a complex noise cancellation process to produce an output signal.