Design of Convolutional Encoder and Viterbi Decoder using MATLAB

The main aim of any communication schemes is to provide error-free data transmission.Error control coding is a method to detect and possibly correct errors by introducing redundancy to the stream of bits to be sent to the channel. This coding has the usefulness that it allows us to increase the rate at which information may be transmitted over a channel while maintaining a fixed error rate. The Convolution (Channel) Encoder will add bits to the message bits to be transmitted systematically. After passing through the channel, at the receiver end the original message sequence is obtained from the received data using Viterbi decoder. It implements Viterbi Algorithm, which is a maximum likelihood algorithm, based on the minimum cumulative hamming distance it decides the optimal trellis path that is most likely followed at the encoder. Convolutional encoding and Viterbi decoding are error correction techniques widely used in Communication systems to improve the bit error rate (BER) performance. In this paper, I present the convolution encoder and Viterbi decoder for constraint length 4 and bit rate 1/2. In addition, a Viterbi decoder is developed in MATLAB