Ultra-Dense, Single-Wavelength DFT-Spread OFDMA PON with Laserless 1.2 Gb/s ONU Ready for Silicon Photonics Integration

We introduce an ultra-dense network architecture designed for silicon photonics at the ONU. This network relies on only 3.333 GSa/s and 417 MSa/s converters at the OLT and ONU, respectively, and offers up to 12 Gbit/s of symmetric traffic in a single 12.5 GHz optical channel. Multiple access and lowest processing speeds at the ONU are enabled by choosing 10 DFT-spread OFDM subbands. We demonstrate this FDMA network architecture in a proof-of-principle experiment with up to eight 300 MBd 16QAM subbands offering a bidirectional data rate of 9.6 Gbit/s. Real-time signal processing is realized for downstream transmission. Finally, we shortly address future improvements of this network architecture by employing integrated silicon photonics and analog signal processing.