A Wideband Receiver I/Q Mismatch Calibration Method in FDD Transceiver.

In this paper, a novel foreground calibration method for wideband zero IF receiver I/Q mismatch is proposed based on frequency domain feature extraction, which is suitable for the FDD transceiver integrated with digital signal processing modules. The proposed algorithm calibrates the frequency dependent mismatch through a complex digital FIR filter, and uses the transmitter as the signal source. A frequency allocation scheme is applied to avoid the interference from the transmitter image component. Mismatch factors such as LO phase and amplitude mismatch and baseband transfer function mismatch can be calibrated together directly by this method, which eliminates the error accumulation caused by multi-level cascade calibration. Finally, a high image rejection ratio is obtained, and the image component power is stably compressed below the quantization noise power in the whole baseband.