Examining System Behaviour in Mode Division Multiplexing for Bidirectional Mobile In-Building Solutions

This paper investigates the feasibility of a bidirectional Mode Division Multiplexing (MDM) system designed for in-building mobile network solutions. Spatial Light Modulators (SLMs) were employed to ensure precise selection of light modes, minimizing the risk of unwanted modes being excited during propagation within the Few Mode Fiber (FMF). The FMF core diameter was chosen to support two specific modes, one dedicated to downlink and the other to uplink transmission. System behavior was analyzed across various fiber lengths to determine potential limitations. Our simulations indicate that this approach could lead to the simplification of Remote Radio Units (RRUs) while maintaining the high-capacity transmission essential for in-building environments.