Low overhead, DC-Balanced and run length limited Line Coding

Abstract

Two main characteristics define the performance of a line coding: the maximum guaranteed run length (RL) which is the number of consecutive identical bits, and the running disparity (RD or DC-Balance) which is the difference between the number of “zeroes” and “ones” in a frame. Both should be bounded to a certain limit, RL to ensure reliable clock recovery and RD to limit baseline wander. In a previous paper, we presented a very low overhead line coding with guaranteed maximum run length. In this paper, we propose a low overhead technique to bound the running disparity that can do up to 10x better than existing encodings in terms of overhead and for the same RD bounds. We furthermore show how we can combine this technique with our former one to build a low overhead, run length limited, and DC-Balanced Line Coding.