Design of Nested Linear/Lattice Code using Field-size Reduction

Abstract It has been demonstrated that lattice-code based communication strategies are beneficial to multi-user multi-hop networks. This paper considers a practical nested linear/lattice code design that achieves near-capacity performance. We propose a new field-size reduction method to realize code nesting for users with different rates. Then, a multi-code extrinsic information transfer (EXIT) chart is executed to design optimized degree distributions. Simulation results demonstrate enhanced BER performance compared to the existing method, and the nested code is less than 0.8 dB to capacity limits. The performance improvement in multi-user systems is demonstrated with linear physical-layer network coding multiple access (LPNC-MA) framework.