List-decoding of variable-length codes with application in joint source-channel coding

The residual redundancy that remains, intentionally or unintentionally, in source-coded systems can be exploited by joint source-channel coding. This principle has been recently applied to variable-length encoded sequences via iterative decoding. This work improved on past results by proposing list-decoding for variable-length codes (VLCs) with the help of a non-binary outer CRC code. We show that the list Viterbi decoding of VLCs is beneficial, particularly for the redundant ones used in state-of-art video coding standards. For a concatenated VLC and channel code, we propose an approximated list-decoder. Since the feasible decoders for concatenated codes are iterative, this proposed list-decoder has as a subset the recently proposed iterative decoder of VLCs and channel codes. The introduced list-decoder improved the overall performance significantly in AWGN and Rayleigh fading channels even with a short list of L=2.