Analysis of Hard Decision and Soft Decision decoding mechanism using Viterbi Decoder in Presence of Different Adaptive Modulations

This paper exhibits the performance of both the hard and soft decision method of decoding for analysis of
different existing adaptive modulation techniques by using Viterbi decoder. In hard decision Viterbi
decoding, the got code word is contrasted and all the conceivable code words and the code word which
gives the base Hamming distance is chosen. While in soft decision decoding all the possible code words
with the minimum Euclidean distance is selected in presence of Additive White Gaussian Noise (AWGN)
channel. The MATLAB codes are executed for signal-to-noise ratio per bit (Eb/No) with respect to bit
error rate (BER) using convolution encoder and optimized Viterbi decoding (HDVD) algorithm. Also the
performance is compared for both the hard and soft decision decoding.