Patent ID: 8175535
Filing Date: 2012-05-08
Classification: H03F,H04B

Abstract:
1. A method of cancelling transmitter leakage in a primary receiver path of a frequency-duplexing transceiver, comprising: generating a radio-frequency (RF) cancellation signal from a transmitter signal; combining the RF cancellation signal with a received RF signal to obtain a combined RF signal comprising a residual transmitter leakage component; converting, in a secondary receiver path, the residual transmitter leakage component of the combined RF signal to a down-converted signal by mixing, in the secondary path, the combined RF signal with a local oscillator signal at a first frequency where the transmitter signal is centered; detecting, in the secondary receiver path, a magnitude of the residual transmitter leakage component from the down-converted signal; obtaining a phase or amplitude adjustment, or both, based on the detected magnitude; and applying the phase or amplitude adjustment, or both, to the RF cancellation signal to reduce the residual transmitter leakage component.