Date Added: Jun 2012
In this paper, the authors propose a new design of LT codes, which decreases the amount of necessary overhead in comparison to existing designs. The design focuses on a parameter of the LT decoding process called the ripple size. This parameter was also a key element in the design proposed in the original work by Luby. Specifically, Luby argued that an LT code should provide a constant ripple size during decoding. In this paper, they show that the ripple size should decrease during decoding, in order to reduce the necessary overhead. Initially they motivate this claim by analytical results related to the redundancy within an LT code. They, then propose a new design procedure, which can provide any desired achievable decreasing ripple size.