An Optimum Combination of Power Levels and Combiner Weighting for Generating 64-QAM from Three 4-PSK Signals

64 state quadrature amplitude modulation (64-QAM) can be generated by combining three 4-PSK signals, thereby allowing nonlinear amplifiers with smaller power ratings to be used. An optimum combination of amplifier power levels and combiner weighting is described which results in no lost power when the peak power state of the 64-QAM signal is being keyed.