Statistics of Group Delays in Multimode Fiber with Strong Mode Coupling

Understand

The modal group delays (GDs) are a key property governing the dispersion of signals propagating in a multimode fiber (MMF).

• A MMF is in the strong-coupling regime when the total length of the MMF is much greater than the correlation length over which local principal modes can be considered constant.
• In this regime, the GDs can be described as the eigenvalues of zero-trace Gaussian unitary ensemble, and the probability density function (p.d.f.) of the GDs is the eigenvalue distribution of the ensemble.
• For fibers with two to seven modes, the marginal p.d.f.