Additive White Gaussian Noise (AWGN) Implementation

In signal transmission systems, AWGN (Additive White Gaussian Noise) can be added to signals using various MATLAB tools including the comm.AWGNChannel System object, AWGN Channel block in Simulink, or the awgn function. This implementation enhances system robustness by increasing the signal's noise floor, thereby improving interference resistance and transmission reliability. The comm.AWGNChannel object provides a comprehensive approach for adding Gaussian noise with configurable parameters such as noise power, signal-to-noise ratio (SNR), and implementation method (signal power or Eb/No). The awgn function offers a simpler syntax: awgn(x,snr) where x is the input signal and snr specifies the signal-to-noise ratio in dB. Prior to transmission, digital signal processing techniques can be applied for modulation and demodulation operations. Common implementations include using comm.QPSKModulator and comm.QPSKDemodulator objects for quadrature phase-shift keying, or comm.PSKModulator/comm.PSKDemodulator for phase-shift keying schemes. These techniques further enhance transmission efficiency and accuracy by optimizing signal characteristics for the communication channel. Key implementation considerations include proper noise power calibration, sampling rate synchronization, and bit error rate (BER) validation using functions like berawgn for theoretical analysis or comm.ErrorRate for practical measurements.