Apple Inc.
CROSSTALK CANCELLATION FOR DIGITAL PREDISTORTION FEEDBACK LOOP

Abstract:

Systems, methods, and circuitries are disclosed to determine parameters for predistortion circuitry in a transceiver including a transmit chain and a receive chain. In one example, a method includes providing a training signal to a power amplifier on the transmit chain. A separation circuitry is controlled to provide an amplified training signal and a first feedback signal is received from the receive chain. The separation circuitry is controlled to output a modified amplified training signal and a second feedback signal is received from the receive chain. Parameters for the predistortion circuitry are determined based the first feedback signal and the second feedback signal.