We experimentally demonstrate an aggregate 86-GBaud (over three sub-bands and one polarization) signal generation based on subcarrier multiplexing technique using IQ mixers, an electrical 90 degree hybrid, and diplexers. The electrical hybrid allows transmitter-side digital signal processing to be simplified to pulse shaping and digital pre-emphasis. We verified the configuration by testing the performance of an 86-GBaud Nyquist-shaped 16 quadrature amplitude modulation signal with differential bit encoding. The implementation penalty assuming 7% hard-decision forward error correction is reduced to 2 dB by utilizing a 31-tap decision-directed least mean square based multiple-input multiple-output equalizer for sideband crosstalk mitigation.
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Funding: Engineering and Physical Sciences Research Council projects PEACE (EP/L000091/1), UPON (EP/M005283/1), SPFS (EP/L00044X/1), TOM3 (EP/M009092/1).
Zhang, T., Sánchez, C., Skvortcov, P., Ferreira, F., Sygletos, S., Phillips, I. D., Forysiak, W., & Ellis, A. D. (2019). 86-GBaud subcarrier multiplexed 16QAM signal generation using an electrical 90 degree hybrid and IQ mixers. Optics Express, 27(8), 11819-11829. https://doi.org/10.1364/OE.27.011819