Abstract: The main objective of the Digital Communication System is to receive data at receiver side as similar as the data sent from the transmitter. To view the system's performance it is important to analyze the system in term of probability of error or bit error rate. In this paper mathematical and simulink curve of BER performances is compared for Gaussian channel for M-ARY PSK. The main objective of this paper is to analysis how much improvements of BER is occurred using M-ARY PSK for Gaussian channel . In order to choose the most suitable modulation for getting better performance several criteria such as power efficiency, bandwidth efficiency, and bit error rate are used for analysis. This paper focuses on error performance of different order of phase modulation schemes in gaussian channel and compare mathematical analysis with simulink analysis

Keywords: Additive white Gaussian noise, Bit error rate, Gaussian channel, Phase shift keying, Signal to Noise ratio.