On unequal error protection raptor codes

Raptor codes are the most advanced fountain codes that can provide dynamically changeable code rate and have linear time encoding and decoding. In multimedia communications and different other areas, it is desired that channel codes can provide the property of unequal error protection (UEP). In this paper, we study two methods to provide UEP Raptor codes on the binary erasure channel (BEC): (1) Using UEP precode (2) Using UEP LT codes. With analysis and thorough simulation we compare the two methods and we conclude that applying UEP in the precode can achieve lower bit erasure rate (BER) for both the more important bits (MIB) and less important bits (LIB).