Adaptively Loaded IM/DD Offset-QAM OFDM Based on Set-Partitioned QAM Formats

We propose an adaptive-loading algorithm for SP-QAM formats, and experimentally show that SP-offset-QAM outperforms conventional offset-QAM and conventional SP-QAM, in adaptive-loaded IM/DD OFDM systems, and achieves >40 Gbit/s at 50 km without any guard interval.