A New Joint Source-Channel Coding Scheme Based on Nested Lattice Codes

In this paper, we propose a new joint source-channel coding (JSCC) method for transmission of a Gaussian source through an additive white Gaussian noise (AWGN) channel whose bandwidth is higher than that of the source. Firstly, a sequence of random variables from a Gaussian source is discretized with a lattice-based quantizer, resulting in a sequence of lattice points. Secondly, by driving an encoder of a systematic group code, these lattice points are utilized to compute a sequence of parity lattice points. Thirdly, both the systematic and the parity lattice points are scaled and transmitted over an AWGN channel. Simulation results show that, with moderate code length, our scheme performs well when compared with the Shannon limits.