Comparison of Modulation Formats for 42.7-Gb/s Single-Channel Transmission Through 1980 km of SSMF

We experimentally compare non-return-to-zero and return-to-zero on-off keying with a number of recently proposed alternative modulation formats for 2000-km 42.7-Gb/s single-channel transmission over standard single-mode fiber. Substantial performance improvements are obtained with the new formats, confirming simulation results and analytical analysis.