Sensors & Transducers (Apr 2014)
Capacity-Approaching Joint Source-Channel Coding for Asymmetric Channels with Low-Density Parity-Check Codes
Abstract
By only sending the parity bits, joint source-channel coding can be natively achieved with low-density parity-check codes. However, the code ensemble design of optimal low-density parity- check codes for joint source-channel coding over asymmetric communication channels is difficult. To circumvent such a difficulty, source-channel adaptors is proposed in this paper. By using the source- channel adaptors both the asymmetric communication channel and the asymmetric correlation channel can be converted to symmetric channel and the conventional design method for channel coding can be used straightforwardly. To demonstrate the effectiveness of the proposed scheme, a code ensemble for joint source-channel coding over asymmetric communication channel is designed for binary memoryless sources with a range of a prior probability. The experiment results show that the performance of the devised codes is very close to the theory limit.
