Design of Low-Power DSP-Free Coherent Receivers for Data Center Links
| Autor: | Anujit Shastri, Jose Krause Perin, Joseph M. Kahn |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
Engineering
Analogue electronics business.industry Optical polarization 02 engineering and technology Phase detector Atomic and Molecular Physics and Optics Phase-locked loop Direct-conversion receiver 020210 optoelectronics & photonics Costas loop 0202 electrical engineering electronic engineering information engineering Electronic engineering Carrier recovery business Phase-shift keying |
| Zdroj: | Journal of Lightwave Technology. 35:4650-4662 |
| ISSN: | 1558-2213 0733-8724 |
| DOI: | 10.1109/jlt.2017.2752079 |
| Popis: | Coherent detection offers high spectral efficiency and receiver sensitivity, but digital signal processing (DSP)-based coherent receivers may be prohibitively power hungry for data centers even when optimized for short-reach applications, where fiber propagation impairments are less severe. We propose and evaluate low-power DSP-free homodyne coherent receiver architectures for dual-polarization quadrature phase shift keying (DP-QPSK) for inter- and intradata center links. We propose a novel optical polarization demultiplexing technique, for DP-QPSK and higher-order modulation formats, with three cascaded phase shifters driven by marker tone detection circuitry. We consider carrier recovery based on either optical or electrical phase-locked loops (PLLs). We propose a novel multiplier-free phase detector based on XOR gates, which exhibits less than 0.5 dB power penalty relative to a conventional Costas loop phase detector. We also study the relative performance of homodyne DP-differential QPSK, for which carrier phase recovery is unnecessary. Our proposed DSP-free architectures exhibit ∼1 dB power penalty at small chromatic dispersion compared to their DSP-based counterparts. We estimate conservatively that the high-speed analog electronics of an electrical PLL-based coherent receiver consume nearly 4 W for 200 Gbit/s DP-QPSK, assuming a 90-nm complementary metal-oxide semiconductor process. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|