Coherent transmissions are more and more frequent. They are not just hero experiments anymore; they are real commercial deployments, done on a daily basis.
However, to achieve the promised reach, low noise amplification is required. In long-haul applications, coherent is increasingly associated with Raman amplification and rightfully so.
Unfortunately, this means chromatic dispersion once again takes center stage.
This is not because to the chromatic dispersion limits on proper transmission, as coherent can handle pretty much any chromatic dispersion thrown at it, but because Raman pump adjustment requires very specific information.
This white paper explores what this is, and why it is that chromatic dispersion will once again play a critical role in coherent–Raman applications.