Soft Decoding of LT-Codes for Wireless Broadcast

Abstract

Abstract — This work investigates reliable wireless broadcast with asynchronous data access. A wireless broadcast system based on LT-codes, a realization of the recently introduced Fountain codes, is introduced. We review the traditional problem formalization for Fountain codes operating on erasure channels and generalize the framework to arbitrary types of channels coining the terminology and the concept of information collecting. Thesum-product algorithm in order to exploit soft-information available at the wireless receiver for decoding of LT codes is applied. Simulation results on the AWGN, as well as the fading channel, show remarkable performance gains compared to traditional erasure decoding. I.