Transceiver with compensation for transmit signal leakage and method therefor

An RF transceiver in which leakage of an RF transmit signal into an RF receive signal is compensated for, said RF communications transceiver comprising:

• an upconversion section of a transmitter portion of said transceiver configured to translate a forward communication signal into said RF transmit signal;
• an analog RF equalizer having an input adapted to obtain said RF transmit signal and having an output which provides a first cancellation signal which is at RF, is derived from said RF transmit signal, and exhibits spectral components which overlap at least a portion of said RF receive signal;
• an analog RF combiner which cancels a first portion of said leakage of said RF transmit signal into said RF receive signal, said analog RF combiner having a first input adapted to receive said RF receive signal, a second input adapted to receive said first cancellation signal and an output which provides a first leakage-compensated receive signal, which is at RF;
• a digital equalizer configured to provide a second cancellation signal, wherein said second cancellation signal is nonlinearly related to said RF transmit signal, is a digitized data stream, is at baseband, and is derived from said forward communication signal;
• a digital downconverter configured to downconvert and digitize said first leakage-compensated receive signal to form a downconverted and digitized receive signal stream;
• and
• a digital combining circuit which cancels a second portion of said leakage of said RF transmit signal into said RF receive signal, said digital combining circuit having a first input adapted to receive said downconverted and digitized receive signal stream, a second input adapted to receive said second cancellation signal, and an output adapted to form a second leakage-compensated receive signal, which is a digitized data stream and is at baseband frequency.

A method of operating an RF transceiver to compensate for leakage of an RF transmit signal into an RF receive signal, said method comprising:

• upconverting a forward communication signal in a transmitter portion of said transceiver to generate said RF transmit signal;
• extracting a portion of said RF transmit signal to form an extracted version of said transmit signal;
• applying a transformation function in an adaptive RF equalizer controlled by tap coefficients, to said extracted version of said transmit signal to generate a cancellation signal, which is at RF and exhibits spectral components which overlap at least a portion of said RF receive signal;
• combining said cancellation signal at RF with said RF receive signal to cancel a portion of said leakage of said RF transmit signal into said RF receive signal and to form a leakage-compensated receive signal, which is at RF;
• downconverted and digitizing said extracted version of said RF transmit signal to produce a baseband downconverted digitized version of said RF transmit signal;
• digitizing said leakage-compensated receive signal to produce a digitized receive signal stream;
• and
• adjusting said tap coefficients of said adaptive RF equalizer in response to said baseband downconverted digitized version of said RF transmit signal and said digitized receive signal stream.