Capacities of WDM transmission systems and networks limited by stimulated Raman scattering

We derive analytic expressions of the ultimate capacity-length-product (CLP) of the wavelength-division-multiplexing (WDM) transmission systems and the ultimate node throughput-length-product (NTLP) of the WDM networks limited by the stimulated Raman scattering (SRS). The CLP and the NTLP are proportional to the square root of the system capacity and the node throughput, respectively. However, they are independent of the system capacity and the node throughput when we compensate for the SRS induced power depletion. The CLP increases as we decrease the amplifier spacing. However, there exists an optimum amplifier spacing that maximizes the NTLP. The analytic results agree well with numerical simulation results.