High-power analog interference cancellation

A device for interference cancellation, comprising:

• a high-power analog interference canceller configured to
• receive (a) a first wireless signal comprising a signal of interest and one or more interfering signals and (b) a reference signal corresponding to a first interfering signal of the one or more interfering signals, wherein the first interfering signal is a high-power interfering signal with a signal power greater than 15 dBm,
• generate, based on the reference signal, a modified reference signal,
• wherein a phase of the modified reference signal is selected from a discrete set of phase values and is substantially inverted with respect to the phase of the high-power interfering signal,
• wherein a gain and a delay of the modified reference signal are substantially similar to the gain and the delay of the high-power interfering signal, respectively,
• wherein determining the phase of the modified reference signal is based on (a) an increment for the discrete set of phase values or (b) a mismatch between the gain and the delay of the modified reference signal and the gain and the delay of the high-power interfering signal,
• output, based on coupling the modified reference signal to the first wireless signal, an interference-canceled signal comprising the signal of interest and a residual of the first interfering signal;
• a radio-frequency stage configured to amplify and filter the interference-canceled signal to generate an amplified and filtered interference-canceled signal, wherein amplifying and filtering the interference-canceled signal comprises boosting the signal of interest and removing out-of-band interference;
• and
• a digital interference canceller configured to perform a digital interference cancellation operation on the amplified and filtered interference-canceled signal.

An apparatus for interference cancellation, comprising:

• an antenna configured to receive an analog signal comprising a signal of interest and one or more interfering signals, wherein the one or more interfering signals comprises a high-power interfering signal with a signal power greater than 15 dBm;
• and
• a processor, coupled to the antenna, configured to:
• determine, based on a reference signal corresponding to the high-power interfering signal, an update to at least one parameter of the reference signal, wherein the update is determined by minimizing a cost function of a difference between the reference signal and the high-power interfering signal, and wherein the at least one parameter comprises a gain, a phase, or a delay,
• generate, based on the update to the at least one parameter, a modified reference signal,
• wherein the phase of the modified reference signal is selected from a discrete set of phase values and is substantially inverted with respect to the phase of the high-power interfering signal,
• wherein the gain and the delay of the modified reference signal are substantially similar to the gain and the delay of the high-power interfering signal, respectively,
• wherein determining the phase of the modified reference signal is based on (a) an increment for the discrete set of phase values or (b) a mismatch between the gain and the delay of the modified reference signal and the gain and the delay of the high-power interfering signal, and
• generate, based on coupling the modified reference signal to the analog signal, an interference-canceled signal comprising the signal of interest.