Method and system for providing a maximum channel capacity in a wavelength division multiplexing transmission system

A wavelength division multiplexing, WDM, system comprising:

• a transmitting transceiver for transmitting optical signals via an optical transmission link to a receiving transceiver using optical wavelengths in a WDM channel grid with a signal symbol rate, SR, each of the optical signals modulated with a modulation format;
• a Reconfigurable Optical Add Drop Multiplexer, ROADM, or another optical filter interposed on the optical transmission link, OTL, between the transmitting and receiving transceivers;
• and
• a controller operatively associated with the transmitting and receiving transceivers and adapted to maximize a channel capacity for each optical channel while maintaining a calculated channel margin, CM, is maintained above a preset minimal channel margin value by iteratively optimizing a system performance parameter, Q, of the optical WDM transmission system, which depends on a link effective bandwidth, BW, of the optical transmission link, OTL, representing the passband-filtering related impairments of the optical transmission link, OTL, and which depends on a generalized optical signal noise ratio, GOSNR, representing the noise related impairments of the optical transmission link, OTL, until the calculated channel margin, CM, is equal or larger than the present minimal channel margin value.

A wavelength division multiplexing, WDM, system design tool implemented in software on a computer and usable for planning an optical wavelength division multiplexing, WDM, transmission system by controlling the computer to perform steps comprising:

• selecting parameters of a software-defined transmitting transceiver and a software-defined receiving transmitter to provide a maximum channel capacity per optical channel using multiple optical channels in a WDM channel grid to transport optical signals modulated with a modulation format and with a signal symbol rate, SR, via an optical transmission link, OTL, along an optical path from the transmitting transceiver to the receiving transceiver, while maintaining a calculated channel margin, CM, above a preset minimal channel margin value, wherein the optical transmission link, OTL, comprises at least one Reconfigurable Optical Add Drop Multiplexer, ROADM or another optical filter;
• and
• wherein selecting the parameters of the transmitting and receiving transceivers includes iteratively optimizing a system performance parameter, Q, of the optical WDM transmission system which depends on a link effective bandwidth, BW, of the optical transmission link, OTL, representing the passband-filtering related impairments of the optical transmission link, OTL, and which depends on a generalized optical signal noise ratio, GOSNR, representing the noise related impairments of the optical transmission link, OTL, until the calculated channel margin, CM, is equal or larger than the present minimal channel margin value.