Experimental implementation of real-time non-orthogonal multi-carrier systems in a realistic fading channel

Spectrally efficient frequency division multiplexing (SEFDM) has the potential to improve spectrum utilization through bandwidth compression at the cost of self-induced inter-carrier interference. In this paper, an experimental test-bed is designed and implemented to evaluate the performance of SEFDM systems in real-time using frequency-domain channel estimation/equalization and iterative signal detection. Our innovation lies in the development and experimental, real-time implementation of baseband generation, signal assembly, signal decoding and a novel frequency-domain channel estimation and equalization method for the SEFDM transceiver. Our system compresses the transmitted signal bandwidth up to 60%, 30% and 20% for BPSK, QPSK and 8PSK respectively, offering significant bandwidth savings, and moving towards satisfying one of the key 5G challenges.