Patent ID: 8804871
Filing Date: 2014-08-12
Classification: H04B,H04J,H04L

Abstract:
1. A method for removing unwanted transmitter emissions from a composite received signal, comprising: extracting digitally I and Q samples from a modulator output; inputting digitally the I and Q samples to a non-linear digital adaptive filter; applying digitally weights to the non-linear digital adaptive filter outputs; combining the non-linear digital adaptive filter outputs digitally to generate a baseband reproduction of the unwanted transmitter emissions; selecting a portion of the reproduction that falls in a desired portion of a receive band by frequency shifting and low pass filtering the reproduction; subtracting digitally the lowpass filtered and frequency shifted reproduction from the composite received signal; and adapting the non-linear digital adaptive filter iteratively, by iteratively adapting the weights applied to the non-linear digital adaptive filter, wherein the weights are a representation of selected Volterra kernels.