TUNING ALGORITHM FOR MULTI-TAP SIGNAL CANCELLATION CIRCUIT

摘要

A self-interference signal cancellation circuit includes a transmitter for transmitting a transmit signal, a plurality of signal paths, a controller, and a receiver for receiving a signal. Each signal path includes a delay element and a variable attenuator having attenuation levels set by the controller. A combiner generates an output signal by combining outputs of the signal paths. The circuit computes a matrix based on first and second output signals associated with first and second attenuation levels. The controller concurrently varies the attenuation level of each signal path so that a product of the matrix and the attenuation levels of the signal paths is substantially equal to the received signal. The circuit may iteratively compute the matrix using different transmit signal frequencies or with an FFT. The controller iteratively varies the attenuation level of the attenuators until a sum of the product and the received signal satisfies a predefined condition.

主权项

1. A circuit comprising:
a transmitter adapted to transmit a transmit signal; a plurality of signal paths, each signal path including a delay element and a variable attenuator and adapted to receive a portion of the transmit signal; a control unit adapted to set one or more signal paths to a first attenuation level and a second attenuation level; a combiner adapted to generate an output signal by combining outputs of the plurality of signal paths; and a receiver adapted to receive a signal, wherein the circuit computes a matrix based on first and second output signals associated with the respective first and second attenuation levels, and wherein the control unit concurrently varies an attenuation level of each signal path so that a product of the matrix and the attenuation level of each signal path is substantially equal to the received signal.