Optical Spectrally Sliced Transmitter for High Fidelity and Bandwidth Scalable Waveform Generation

This paper presents a single-carrier optical coherent transmitter that synthesizes high-fidelity waveforms from
N
spectral slices with the state-of-the-art electrical drivers. The synthesis technique overcomes the electronic speed bottlenecks and produces an optical waveform bandwidth that is
N
times the electrical bandwidths. Using two 32 GHz slices, we synthesized and transmitted a 60-GBd polarization-division multiplexed, quadrature phase-shift keying (PDM-QPSK) waveform over 4480 km with a Q
²
-factor of 8.71 dB. To demonstrate high-fidelity waveform synthesis, we generated a 60-GBd PDM 16-QAM and observed a 2.5-dB implementation penalty at BER of 1×10
^–2
. To address scalability, we also developed the phase mismatch compensation algorithm for the transmitter that uses photonic integrated circuits.