Cancellation of Spurious Responses From Local Oscillator Cross-Coupling

摘要

Interference cancellation techniques may be implemented in a radio transceiver configured to transmit a radio-frequency transmit signal at a transmit frequency and having two or more local oscillators operative to simultaneously generate local oscillator signals, at corresponding local oscillator frequencies, for simultaneously down-converting two or more corresponding received radio-frequency signals. An example method begins with identifying one or more self-interfering frequencies, based on the local oscillator frequencies and the transmit frequency. A baseband cancellation signal is then generated by weighting and frequency-shifting a baseband representation of the transmit signal, based on the identified self-interfering frequencies. The baseband cancellation signal is then combined with a down-converted received signal, to obtain an interference-reduced baseband signal.

主权项

1. A method, in a radio transceiver configured to transmit a radio-frequency transmit signal at a transmit frequency and having two or more local oscillators operative to simultaneously generate local oscillator signals, at corresponding local oscillator frequencies, for simultaneously down-converting two or more corresponding received radio-frequency signals, the method comprising:
identifying one or more self-interfering frequencies, based on the local oscillator frequencies and the transmit frequency; generating a baseband cancellation signal by weighting and frequency-shifting a baseband representation of the transmit signal, based on the identified self-interfering frequencies; and combining the baseband cancellation signal with a down-converted received signal, to obtain an interference-reduced baseband signal.