Improved design of expanding window fountain codes over BIAWGN channels

Abstract

In this paper, we propose an improved design of expanding window fountain (EWF) codes over the binary input additive white Gaussian noise (BIAWGN) channels. The encoding process is modified to get almost regular variable node degree distributions. Compared with the conventional EWF codes, our proposed scheme can lower the error floor. Furthermore, we combine the EWF encoding process with unequal power allo-cation to improve unequal error protection (UEP) performance. Both asymptotic analysis and simulation results show that the proposed scheme can get better UEP performance and design flexibility.