Implementation of 16-QAM algorithm in the presence of AWGN channel

This algorithm implements the 16-QAM modulation and demodulation in the presence of AWGN channel

Description

The program take an input stream of first 16 integers converted to binary form in the form of 4 bits least pass them on to the 4-bit register which takes first 2 bits to the I-channel and the next 2 bits to the Q-channel for modulation with cos and sin carriers respectively. After the modulation, both the signals are added and the resultant is transmitted over an AWGN channel which distorts the signal before it reaches the receiver. At the receiver end the signal is detected and demodulated separately with sin and cos waves for the separation of I and Q channels. Both the signals are passed through LPFs and average value for each interval is calculated and out put bits are generated accordingly. Muxing these two streams result in the generation of output sequence wich is definitely same as the given input. The program also shows the constellation diagram for both the transmitted and the distorted received signal. Almost all the signals through the whole system are shown in the different plots to ensure better understanding of how the program works.

• Required Products: MATLAB
• MATLAB release: MATLAB 7.0.4 (R14SP2)