On Trellis Structure of Error Correction Coding |
The modern trends in communication field points towards achieving the fastest way of data transmission through communication line, reaching Shannon’s Channel Limit. The key to these developments is error correction coding technique which is currently employed in broadband satellite communication and data storage. Constructing Trellis for the codes - a graphical way of code analysis that allows us to avoid repeating the same computations over and again - reduces the decoding complexity, thereby improves transmission efficiency. The paper will investigate the way trellises are constructed for different types of codes, how their complexity can be reduced and how they are used to correct errors on transmission channels. This includes study of trellis pattern for different coders – for both convolutional and block codes and its implementation in a practical communication channel using Monte Carlo Simulation technique. A brief comparison of bit error rate for hard and soft decision decoding techniques for selected coders and for different message lengths is performed with BER Vs SNR plots.
Mathew J, Ambroze MA