Comparison of Performance of 16-ary QASK and MSK Over a Frequency Selective Rician Fading Channel

The probability of error of both a 16-ary QASK system and an MSK system, each operating over a Rician fading channel, is considered. The channel model has two key features: short term variations are modeled by making the channel frequency selective, and long term variations are accounted for by allowing the specular component of the received signal to fade according to a Rayleigh density. The improvement gained by using maximal-ratio diversity combining is derived, as well as the degrading effects of an adjacent channel. Finally, a comparison between MSK and 16-ary QASK operating over the same channel is presented, and it is shown that MSK results in a smaller probability of error.