100.29-Gb/s direct detection optical OFDM/OQAM 32-QAM signal over 880  km SSMF transmission using a single photodiode

We propose a novel guard-band-shared direct-detection (GBS-DD) scheme for a 100-Gb/s single-photodiode direct-detection transmission system. The 100.29 Gb/s signal is successfully transmitted over 880 km standard single mode fiber (SSMF) with Raman amplification under the 20% forward error correction (FEC) threshold within 52 GHz optical bandwidth. The signal is modulated with orthogonal frequency-division multiplexing/offset quadrature-amplitude-modulation 32-ary QAM (OFDM/OQAM 32-QAM). The signal-to-signal beat interference (SSBI) terms fall and overlap in the same guard band. Adopting the proposed approach, the bandwidth usage efficiency of the photodiode is greatly enhanced, which brings benefits on the data rate and transmission performance.