A data puncturing IR-scheme for type-II hybrid ARQ protocols using LDPC codes

We present a data puncturing (DP) type-II hybrid ARQ protocol with low-density parity-check (LDPC) codes. Incremental redundancy is created from punctured versions of the original data using the same encoder/decoder hardware. Thus, parts of the initially received data can be gradually improved until successful decoding of the entire code is possible. In comparison to a rate-compatible (RC) type-II hybrid ARQ scheme, a much higher rate LDPC code can be used for encoding/decoding. The proposed approach combines low hardware overhead with high worst case decoding performance. This combination has not been achieved with other schemes so far. The principle is therefore especially suitable for mobile applications. Further, performance analysis shows that the proposed scheme significantly outperforms a type-III HARQ protocol with diversity combining in terms of data throughput.