Transmission efficiency of multimode-single mode-multimode fiber based on the coupled mode theory

In this paper, we present a numerical simulation of the transmission efficiency of multimode-single mode-multimode fiber structures through adopting the coupled mode theory. The total transmission efficiency, which is defined as the ratio between output light power of the fiber end and input light power of fiber head, has been calculated to be 48.51%. Our experimental result of the ratio is measured to be 47.48%, which has a good agreement with the numerical simulation result. Therefore, our theoretical method is helpful in the area of optical fiber sensors and communications.