400-Gb/s Single-Photodiode Polarization-Agnostic Kramers-Kronig Reception of Distributedly Aggregated Superchannel

摘要： In its most simple implementation, the Kramers-Kronig (KK) scheme allows the reception of complex modulation formats with a single photodiode. Thereby, in analogy to a heterodyne receiver, an additional continuous wave signal is used which allows under certain conditions the distortion-free reconstruction of the data signal. We present experimental investigations on a novel Kramers-Kronig scheme based on inherently carrier generation at the receiver. We use a distributed superchannel aggregation scheme to demonstrate ultra-wideband single-photodiode reception of a 3×33-GBd single-polarization 32QAM superchannel with this scheme. The impact of polarization rotations is discussed, and we show that variations in data or Kramers-Kronig carrier polarization will only affect the carrier-to-signal power ratio (CSPR), leading to an increase or decrease from the optimum CSPR by about 6 dB. 400-Gb/s net capacity is demonstrated for optimized conditions. In addition, we demonstrate transmission measurements over a 60-km standard single-mode fiber (SSMF) link with a 344-Gb/s net rate superchannel (3×28 GBd sub-carriers) with the novel Kramers-Kronig scheme.