What Type Of Encoding Was Introduced To Improve The Performance Of Line Coding?

To improve the performance of the line encoding schemes, the block encoding was introduced. As you know that we need some kind of redundancy to ensure the synchronization. In addition to this, we also need to include some other redundant bits to detect errors. Block coding can achieve, to some extent, both these two goals. There are three main steps that are used in transformation. These are the division, the substitution and the line coding. In first step that is division; the sequence of bits is divided into the groups of m bits. For example in case of 45/52 encoding, the original bit sequence is divided into 4-bit groups. The heart of block coding is the substitution step. In this step we substitute an m-bit code for an n-bit group. The third step is the line coding. After the substitution, we can use one of the line coding schemes to crate a signal. Normally a very simple line coding scheme is chosen because the block coding procedure provides two desirable features of complex line coding schemes. In certain situations it is necessary to combine the third step (substitution) and the fourth step (line coding). Block coding can definitely help in error detection.