System and method for m-ary phase shifting keying modulation. According to an embodiment, the present invention provides a method for performing m-ary phase-keying shift modulation. The method includes providing at least a first signal and a second signal by a signal source. The first signal and the second signal are characterized by a first signal strength level. The method also includes attenuating the second signal to provide a third signal. The second signal are characterized by a second signal strength level which is at approximate 50% of the first signal strength level. The method additionally includes coupling the first signal to a first bias voltage to provide a fourth signal. Furthermore, the method includes coupling the third signal to a second bias voltage to provide a fifth signal. The method also includes a step for providing a sixth signal by combing the fourth signal and the fifth signal.