A Study of Power Distributions in Photonic Lantern for Coherent Optical Receiver

We study the power distributions at single-mode fiber end of the non-mode-selective photonic lantern for the coherent optical receiver using multivariate Gaussian distribution and uniform distribution. Equal-gain combining is used to combine the electrical signals at the outputs of the balanced photodetectors. The signal-to-noise ratio is studied for the coherent optical receiver. It is found that, when the number of single-mode fibers of the photonic lantern is equal to the number of guided modes at multimode end of the photonic lantern, the average signal-to-noise ratio attains its maximum value.