A New Ensemble of Rate-Compatible LDPC Codes
  In this paper, we presented three approaches to improve the design of Kite codes (newly proposed rateless codes), resulting in an ensemble of rate-compatible   LDPC codes with code rates varying "continuously" from 0.1 to 0.9 for additive white Gaussian noise (AWGN) channels. The new ensemble rate-compatible LDPC codes can be constructed conveniently with an empirical formula. Simulation results show that, when applied to incremental redundancy hybrid automatic repeat request (IR-HARQ) system, the constructed codes (with higher order modulation) perform well in a wide range of signal-to-noise-ratios (SNRs). 
Kai Zhang, Xiao Ma, Shancheng Zhao, Baoming Bai and Xiaoyi Zhang
cs.IT math.IT