Spatially distributed optical fibre based transmission link and method thereof

A method for reducing and/or minimizing the energy consumption and/or the cost of an optical fiber based transmission link characterized by having an optical signal-to-noise-ratio (OSNR) and desired total capacity CTotal, the method comprising:

• calculating a received signal-to-noise ratio (SNR01) in a single spatial channel in the transmission link based on the OSNR of the transmitted optical signal through the link, or assuming a given SNR01, as determined by a given link design, wherein the single spatial channel has only one optical fiber;
• calculating the corresponding capacity C01 of the single spatial channel, determined by the SNR01, and calculating a number of single spatial channels (Nfiber) required in the link to obtain a predefined desired total capacity CTotal=Nfiber·C01;
• whilst maintaining the same total capacity of the link, distributing the total capacity CTotal of the link in S=m·Nfiber spatial fiber channels, calculating a required signal-to-noise ratio SNR0m for each of the S spatial fibre channels to support the capacity CTotal/S, where m is between 1 and 2, or 2, or greater than 2, and wherein S is an integer;
• for each fiber calculating a required repeater spacing in each spatial fibre channel to obtain the required SNR0m;
• and
• determining the number of m that provides the minimum number of repeaters.