A fast accurate method for calculating symbol error probabilities for AWGN and Rayleigh fading channels

In order to improve the quality of communications systems, network researchers and designers need to understand the error performance of radio channels that influence the choice of coding and modulation schemes, and network architectures. Symbol and bit error probabilities are great methods to measure the performance of the radio channels. However, in many cases the exact expressions of symbol and bit error probabilities are very complex due to the diversities of error environments in a wireless channel. Thus, it is beneficial to have simple approximate expressions, to simplify expression manipulations. In this paper, simplified expressions for the symbol error probability over AWGN and Rayleigh fading channels are presented which are found to be in good agreement with the original expressions. More precisely, the simplified expressions are in the form of one term exponential and rational functions for AWGN and Rayleigh fading channels, respectively.