Systems and methods for measuring I-Q mismatch

A method of measuring I-Q mismatch in a system having a transmitter, the transmitter comprising an in-phase up-converter, a quadrature-phase up-converter, and a power detector, the method comprising:

• measuring an in-phase transmit power at the power detector caused by transmitting an in-phase output signal to the in-phase up-converter;
• measuring a quadrature-phase transmit power at the power detector caused by transmitting a quadrature-phase output signal to the quadrature-phase up-converter;
• calculating a transmitter-gain-mismatch as a function of the in-phase transmit power and the quadrature-phase transmit power;
• measuring an I-Q transmit power at the power detector caused by simultaneously transmitting a gain-mismatch-compensated in-phase output signal to the in-phase up-converter and a gain-mismatch-compensated quadrature-phase output signal to the quadrature-phase up-converter;
• and
• calculating a transmitter-phase-mismatch as a function of the I-Q transmit power,
• wherein the step of calculating the transmitter-gain-mismatch comprises solving the equation G13 m=√{square root over (PI/PQ)}, where G13 m, is the transmitter-gain-mismatch, PI is the in-phase transmit power, and PQ is the quadrature-phase transmit power.