US 11,469,821 B2 · Interference cancellation methods and apparatus

Abstract

Methods and apparatus for interference cancelation in a radio frequency communications device are described. In various embodiments a signal to be transmitted in converted into an optical signal and processed using an optical filter assembly including one or more optical filters to generate an optical interference cancelation signal. The optical interference cancelation signal is converted into an analog radio frequency interference cancelation signal using an optical to electrical converter prior to the analog radio frequency interference cancelation signal being combined with a received signal to cancel interference, e.g., self interference. The optical filter assembly can include a large number of taps, e.g., 30, 50, 100 or more. Each tap may be implemented as a separate optical filter or series of optical filters. Delays and/or gain of the optical filters can be controlled dynamically based on channel estimates which may change due to changes in the environment and/or communications device position.

Claims19

Dependent claims

A radio frequency (RF) communications device comprising:

a first antenna configured to transmit a first RF signal at a first carrier frequency;
a second antenna configured to receive a second RF signal at a second carrier frequency;
an RF-to-optical converter configured to:
receive as input the first RF signal;
and
provide as output an optical output signal based on the first RF signal;
an optical filter assembly configured to filter the optical output signal to generate a filtered optical signal;
an optical-to-RF converter configured to:
receive as input the filtered optical signal;
and
provide as output a third RF signal based on the filtered optical signal;
and
a signal combiner for combining the third RF signal and the second RF signal to generate a recovered received RF signal from the second RF signal.

10 more elements

An RF communications device comprising:

a first radio defining at least in part a first full duplex channel and configured to receive a first RF signal over the first full duplex channel and to transmit a second RF signal over the first full duplex channel;
and
a second radio defining at least in part a second full duplex channel and configured to receive a third RF signal over the second full duplex channel and to transmit the first RF signal over the second full duplex channel, the second radio comprising:
an antenna configured to transmit the first RF signal over the second full duplex channel, thereby relaying the first RF signal from the first full duplex channel to the second full duplex channel;
a self-interference filter configured to:
convert, to an optical signal, at least a portion of at least one of:
the second RF signal as transmitted by the first radio;
or
the first RF signal as transmitted by the second radio;
filter the optical signal with an optical filter to output a filtered optical signal;
and
convert the filter optical signal to a filtered RF signal;
and
a RF combiner to merge the filtered RF signal with the third RF signal to generate a recovered received RF signal from the third RF signal.

11 more elements

Dependencies are inferred from the claim text.

Interference cancellation methods and apparatus

Life of this patent

Interference cancellation methods and apparatus

Life of this patent

Abstract

Claims19