Abstract :
This paper compares the basic modulation for digital transmission: MPSK, (Multiple Phase Shift Keying), MQAM, (Multiple Quadrature Amplitude Modulation), MFSK (Multiple Frequency Shift Keying). The comparison shows that the probability of error per bit, BER (Bit Error Rate, BER) is the basic parameter for determining the quality of any digital transmission. With a description of the basic existing configuration and characteristics of their transmitters and receivers, using the Matlab program, we provide estimates for each modulation process via computer simulation. In addition we present an example of defining the spectral efficiency of these modulation procedures (MPSK, MQAM, MFSK).
