1. A method of calibrating a wireless transmitting device, comprising:determining a propagation delay mismatch between a first test signal on a first signal path of the wireless transmitting device and a second test signal on a second signal path of the wireless transmitting device, wherein determining the propagation delay mismatch comprises:
transmitting the first test signal having a first frequency on the first signal path;
transmitting the second test signal having a second frequency different from the first frequency on the second signal path;
measuring a phase difference between the first test signal and the second test signal; and
determining a delay measurement between the first test signal and the
second test signal based at least in part on the measured phase difference;
determining the propagation delay mismatch using a difference between the delay measurement and a previously determined delay measurement; and
adjusting delay circuitry of at least one of the first signal path and the second signal path to compensate for the propagation delay mismatch.