Fully compensated adaptive interference cancellation system

摘要

A system for removing interference comprising a receive decimation filter that accepts a composite received baseband signal and generates filtered sampled data at a decimation rate, a transmit decimation filter that accepts a digitally converted replica of an interfering signal and generates filtered sampled data at a decimation rate, an integer sample delay control (ISDC) that provides multiple sample delay control for the replica and stores an estimated delay value, an adaptive filter that provides fractional sample delay control for the replica of the interfering signal and optimizes cancellation of the interfering signal, a digital phase-locked loop (DPLL) programmed with a known frequency offset of the interfering signal that tracks a phase and frequency of the replica of the interfering signal, an automatic gain control (AGC) that maintains near full scale operation of adaptive filtering and the DPLL, and a slicer, mixer, and delay unit forming an error estimator.

主权项

1. A system for removing interference from a composite received baseband signal comprising:
an integer sample delay control (ISDC) configured to provide multiple sample delay control for a replica of an interfering signal and store an estimated delay value; an adaptive filter coupled to the ISDC and configured to provide fractional sample delay control for the replica of the interfering signal and optimize cancellation of the interfering signal present in the composite received baseband signal that comprises the interfering signal and a desired signal; a digital phase-locked loop (DPLL) coupled to the adaptive filter and programmed with a known frequency offset of the interfering signal that tracks a phase and frequency of the replica of the interfering signal; an automatic gain control (AGC) coupled to the adaptive filter and configured to maintain near full scale operation of adaptive filtering and the DPLL; and an error estimator comprising a mixer, a delay unit, and a slicer configured to update a coefficient of the adaptive filter.