Is the Weak Coupling Nonlinear SDM Channel Worse Than the Strong Coupling One?

The two working regimes of strong (SCR) and weak coupling (WCR) for multimode fibers (MMF) for space-division multiplexing are compared in terms of nonlinearity and achievable data rates. Leveraging recently developed perturbative models and considerations on MMF parameters, hints are provided that the WCR can achieve similar or higher rates than the SCR. Some considerations on power allocation over frequency channels and modes are provided.