Enhanced Joint Source-Channel Polarization Effect based on Polarizing Matrix Extension

In this letter, we propose a joint source-channel coding scheme based on polarizing matrix extension (PME-JSCC). The PME-JSCC can combine channel received signal and source side information to form a longer polar code. We extend the source encoding matrix and place channel bits on the extended bits. Due to the lower triangular structure of the polarizing matrix, source bits will not be changed by channel bits. The PME-JSCC can obtain enhanced joint source-channel polarization (JSCP) effect. This effect enhances the reliabilities of both channel bits and source encoded bits simultaneously. The bound on the block error probability for PME-JSCC is improved. And the PME-JSCC can be proved to reach the fundamental limit on JSCC. Simulation results show that the PME-JSCC scheme outperforms the DP-LDPC and the D-Polar codes under the joint successive cancellation list (J-SCL) decoder and can approximate the JSCC finite length bound in the short blocklength regime.