Patent ID: 9331737
Filing Date: 2016-05-03
CPC Classification: H04B

Claim Text:
1. A wireless communication device comprising: at least one antenna for receiving or transmitting a signal; a cancellation circuitry adapted to receive a first sample of a transmit signal, said cancellation circuitry comprising: a control block; a subtractor; N paths, each path comprising a delay element and an associated variable attenuator whose attenuation level varies in response to the control block, each path receiving the first sample of the transmit signal and generating a delayed and weighted version of the first sample of the transmit signal; wherein a delay element disposed in a first one of the N paths generates a delay shorter than a self-interference arrival time, and wherein a delay element disposed in a second one of the N paths generates a delay longer than the self-interference arrival time; wherein the self-interference arrival time is a delay between arrival of a second sample of a transmit signal at the cancellation circuitry and arrival of a corresponding self-interference signal at the subtractor; wherein the corresponding self-interference signal comprises self-interference resulting from transmission of the second sample of the transmit signal; a combiner adapted to combine the N delayed and weighted versions of first sample of the transmit signal to construct a signal representative of a first portion of a self-interference signal; wherein the subtractor is adapted to subtract the constructed signal from a received signal, wherein N is an integer greater than or equal to 2.