Performance Assessment and Computer Simulation of the M-ary QAM Modulation Scheme

The most important issue in digital communication system is to receive data as similar as the data sent from the transmitter with a high speed using less channel bandwidth. This means that it is important to test the systems in terms of probability of error to view the system's performance. Each modulation technique has different performance while dealing with signals, which normally are affected with noise. One of digital modulation scheme is used is known as an M-ary Quadrature Amplitude Modulation (M-ary QAM) .In this paper performances investigation and computer simulation of M –ary QAM has been carried out for different number of levels symbols using powerful scientific software known as a Matlab with Simulink V. 2018. When increasing the number of levels, the simulated result, show that the bit error rate (BER) decrease but generally M-ary QAM is more bandwidth efficient than other M- ary modulation systems types.