Wireless circuitry with loop-back path all-pass filter

An electronic device may include wireless circuitry having a baseband processor, a transceiver, and an antenna. The transceiver may include a transmit path, a receive path, and a loop-back path coupling the transmit path to the receive path. A passive all-pass filter may be interposed on the loopback path. A control circuit may use the all-pass filter to calibrate I/Q mismatch of the wireless circuitry to optimize radio frequency performance of the wireless circuitry. Performing I/Q mismatch calibration using the all-pass filter may be used to minimize area consumption in the transceiver, may minimize calibration time, and may allow calibration over a relatively wide bandwidth. 一种电子设备可包括具有基带处理器、收发器和天线的无线电路。该收发器可包括发射路径、接收路径以及将该发射路径耦接到该接收路径的回环路径。无源全通滤波器可插置在该回环路径上。控制电路可使用该全通滤波器校准该无线电路的I/Q失配，以优化该无线电路的射频性能。使用该全通滤波器执行I/Q失配校准可用于最小化该收发器中的面积消耗，可最小化校准时间，并且可允许在相对宽的带宽上进行校准。