Regresar

Comparing DMT variants in medium-reach 100G optically amplified systems

Abstract:

Several research works are currently addressing 100+ Gbps per wavelength high-capacity dense wavelength division multiplexing (DWDM) medium reach systems (80 km on SMF fibers) to cover the metro market segment. For the purposes of cost reduction, it is interesting to consider the use of direct detection receivers rather than the more expensive coherent receivers. However, DWDM transmission in the C-Band imposes severe limitations in terms of tolerances to chromatic dispersion, electrical low-pass filtering, analog-to- digital converter and digital-to-analog converter quantization effects, and receiver optical signal-to-noise ratio (OSNR). In this paper, we analyze the ultimate performance of several variances of discrete multitone (DMT) modulation (namely dual-sideband DMT, single-sideband, and vestigial-sideband), comparing them in terms of required OSNR as a function of several system parameters in a medium reach scenario. We found that for the 80 km target link only single-sideband DMT seems a viable option, while double-sideband DMT has exceedingly high OSNR requirements.