Entropy loading for multicarrier optical systems

Abstract

Optical fiber channels present flat channel response per wavelength in general, owing to the ultra-wide available bandwidth of optical fiber and optical amplifiers. However, the recent transport capacity upgrade per wavelength from 10 to >100 Gbaud has given rise to severe power fading at the high frequency range. Especially, the modern optical networks may rely on a massive number of reconfigurable optical add and drop multiplexers (ROADM) to enhance the network flexibility with low latency. These cascaded ROADMs bring about a well-known filter-narrowing effect that has become a severe issue in the deployed networks. This strongly limits the channel bandwidth, and leads to an optical channe..