Calculation Model for Multimode Fiber Connection Using Measured Near- and Far-Field Patterns

For fiber optic links in the optical transmission systems of short-distance local area networks, connector loss testing is performed before the connector is implemented in the system to ensure that the loss budget requirements are satisfied. We propose a calculation model that can be widely used for practical application of multimode optical fiber connections in loss testing of transmission systems. The proposed model uses the measured data of the near- and far-field patterns of a launch fiber output light under arbitrary launch conditions, such as the light source. To evaluate the proposed model, the connection losses of the step- and graded-index multimode fibers were estimated for the lateral and axial displacements of the optical axis; the simulated data were found to be highly consistent with the measured data. This method is highly versatile as it can be applied to any multimode fiber type, whether step-index or graded-index multimode fiber.