DSP-Enhanced Analog-to-Digital Conversion for High-Speed Data Centers' Optical Connectivities

Yaron Yoffe, Dan Sadot
2015 IEEE Photonics Journal  
As data centers evolve to sustain the economic scale in network traffic, optical interconnections are adapted to support the vast amount of capacity requirements. Among emerging solutions is the incorporation of digital-signal-processing (DSP) functionalities at the receiver to compensate for the optical fiber and optoelectronic components impairments. The bottleneck in such architecture is often implementing a high-resolution and high-speed analog-to-digital-converter (ADC) device, which
more » ... device, which usually leads to massive power consumption and high costs. In this paper, we propose novel transmission schemes based on low-resolution ADCs, termed DSP-enhanced analog-todigital conversion. The proposed methods are based on the mathematical principle of predictive quantization, combined with linear equalization theory. Mathematical analysis and performance bounds associated with common channel impairments are derived. Simulation results demonstrate that the DSP-enhanced ADC provides a significant signal-to-noise-ratio (SNR) gain and, subsequently, may enable heavy digital compensation with reduced-resolution ADCs. Index Terms: Fiber-optic communications analog-to-digital conversion (ADC), quantization, bit error rate (BER), differential pulse code modulation, inter-symbol interference (ISI), linear equalization.
doi:10.1109/jphot.2015.2458911 fatcat:owkacb3upnab7nt2rainphefaq