Inter-Carrier Interference Suppression in No-Guard-Interval Orthogonal Frequency-Division-Multiplexing System

The inter-carrier interference (ICI) in the no-guard-interval orthogonal frequency-division-multiplexing (NGI-OFDM) system causes severe performance degradation when 2-samples/symbol (Sa/sym) digital signal processing (DSP) is used at the receiver. To enable narrow bandwidth devices and low sampling rate DSP, a novel ICI suppression (ICIS) method is proposed and experimentally demonstrated in this letter. The proposed method improves the performance of the 4-Gbaud 25-carrier NGI-OFDM system by up to 4 dB, and 2-Sa/sym DSP with ICIS achieves comparable performance as the conventional 8-Sa/sym DSP without ICIS, with moderately increased complexity.