Analog Network Coding for Multi-User Multi-Carrier Differential Chaos Shift Keying Communication System

This paper presents the design and performance analysis of an analog network coding (ANC) scheme for multi-user multi-carrier differential chaos shift keying (MC-DCSK) modulation. The incentives to employ the MC-DCSK system are to achieve a better spectral efficiency and more efficient energy consumption compared to that of a conventional DCSK system. The proposed scheme considers a network comprising L user nodes (L ≥ 2) and a single relay node R. In this scheme, called the ANC-based two-way relay system, all users transmit their signals to the relay in the first time slot, and the relay forwards the superposition of the received signals each of the user nodes in the second time slot. At the receiver end, each user mitigates the overall interference by subtracting its own data signal from the received combined signal and then starts the decoding process. The system design is analytically studied, and the corresponding theoretical bit error rate expression for the multipath fading channel is derived. Additionally, the conventional ANC-DCSK scheme is analyzed and compared to the proposed ANC-based MC-DCSK scheme to show the improvement in the performance of our approach. Finally, to validate the accuracy of the methodology, the simulation results are compared to the related theoretical expressions.