Transmission of Audio Signal From Linear Block Coded AWGN Channel Using Different Modulation Techniques and Wavelet Transform Families

Abstract

Mobile communication has become an important part of our daily lives for voice communication and data sharing and access over the Internet. Mobile communication is an open network, so maintaining the privacy and reliability of data has always been anxiety. The reliability of the data against channel noise can be achieved by various error correction codes. The purpose of the channel coding process is to reduce the effect of some disruptive elements that the information is influenced in the transmission phase as much as possible, that is to ensure that the data is delivered to the receiver with minimum error. In the first(1) part of this work, Linear Block Coding Method is used to transmit the audio data recorded in wav format for 5 seconds in MATLAB environment with minimum error. Four different types of modulation were used as the modulation method and the best performance was obtained by using Binary Phase Shift Keying (BPSK). The Bit Error Rate (BER) performance curve was drawn and the difference between the original and the received signal was observed. According to the BER performance curve, as the signal to noise ratio increases, less false data is received at the receiver. In the second part of the study, four wavelet transforms at different levels were applied to the audio signal, and the performances of these families were compared.