Quasi-regular rate-compatible LDPC codes with a novel diagonal-tailed encoding on noisy channels

It is well known that conventional rate-compatible (RC) codes, such as Raptor codes, only perform well at long code lengths. However, we propose a class of RC codes with short code lengths in this paper. Particularly, we develop a computational approach to design online-generated RC low-density parity-check (LDPC) codes available on noisy channels. We first propose a diagonal-tailed encoding to generate Quasi-regular low-density generator matrix codes. Then, an optimal encoding profile for RC codes is achieved with a linear interpolation approach that is based on the fixed-rate quasiregular LDPC codes. Finally, we evaluate the rateless and fixed-rate performances of the proposed RC codes by extensive simulation results on various code rates with different modulations.