US 8,787,860 B2 · Image cancellation in receivers using dual adaptive filters

Abstract

The present disclosure includes apparatus, systems, and techniques relating to receiver image cancellation. A described technique includes receiving a downconverted signal in a digital domain, the downconverted signal including an in-phase signal and a quadrature signal; generating a first signal of a signal channel based on the downconverted signal; generating a second signal of an image channel based on the downconverted signal; filtering the second signal using first weights to produce a pilot training signal; filtering the second signal using second weights to produce an image cancellation signal; generating an output signal by subtracting the image cancellation signal from the first signal to resolve the desired signal; updating the first weights based on the first weights, the second signal, the pilot training signal, and a pilot signal; and updating the second weights based on the second weights, the output signal, and the pilot training signal.

Claims22

Dependent claims

A method comprising:

receiving a downconverted signal in a digital domain, the downconverted signal comprising an in-phase signal and a quadrature signal;
generating a first signal of a signal channel based on the downconverted signal;
generating a second signal of an image channel based on the downconverted signal;
filtering the second signal using first weights to produce a pilot training signal;
filtering the second signal using second weights to produce an image cancellation signal;
generating an output signal by subtracting the image cancellation signal from the first signal to resolve a desired signal;
updating the first weights based on the first weights, the second signal, the pilot training signal, and a pilot signal;
and
updating the second weights based on the second weights, the output signal, and the pilot training signal.

6 more elements

A system, comprising:

a radio frequency interface configured to receive a communications signal comprising a desired signal;
a combiner configured to add the communications signal and a version of a pilot signal to produce a combined signal;
an analog hardware section configured to perform a quadrature downconversion on the combined signal to produce a downconverted signal in a digital domain, the downconverted signal comprising an in-phase signal and a quadrature signal;
a memory structure configured to store data comprising first weights and second weights;
and
a processor, communicatively coupled with the combiner, the analog hardware section, and the memory structure, the processor configured to perform operations comprising
generating the pilot signal,
generating a first signal of a signal channel based on the downconverted signal,
generating a second signal of an image channel based on the downconverted signal,
filtering the second signal using the first weights to produce a pilot training signal,
filtering the second signal using the second weights to produce an image cancellation signal,
generating an output signal by subtracting the image cancellation signal from the first signal to resolve the desired signal,
updating the first weights based on the first weights, the second signal, the pilot training signal, and the pilot signal, and
updating the second weights based on the second weights, the output signal, and the pilot training signal.

11 more elements

Dependencies are inferred from the claim text.

Image cancellation in receivers using dual adaptive filters

Life of this patent

Image cancellation in receivers using dual adaptive filters

Life of this patent

Abstract

Claims22