Traditional, Lengthened and Shortened LT Codes Comparison

Shortened and lengthened systematic Luby Trans- form Codes (LT-codes) have been shown, in this paper, to perform better than their equivalent mother codes by simulating trans- mission of LT-coded information over a binary erasures channel. The performance is improved as the shortening (lengthening) factor is increased while reducing (keeping) its complexity, when compared to the complexity of the mother code. The reported performance of both shortened and lengthened systematic LT- codes were obtained by designing the codes by using a truncated robust soliton degree distribution. Our results shows also that systematic LT-codes (despite the degree distribution) performs better than non-systematic LT-codes.