Mathematical Model, Simulated Design and Experimental Results for Parabolic Mirror Based Multiplexer for Spatially Multiplexed Fiber Optic Communication Systems
Spatial Domain Multiplexing (SDM) is a multi-input multi-output (MIMO) architecture. It adds an innovative dimension to optical fiber communication systems by enabling spatial reuse of the optical frequencies. SDM utilizes radially distributed spatial locations for different input signals based on their input launch angles. These input channels propagate in a helical path inside the carrier fiber. These SDM input channels do not encounter any perceptible cross-talk or inter-symbol interference. The SDM system is similar to other optical communication systems. However, they require two added parts. These parts are the spatial multiplexer, also known as the Beam Combiner Module (BCM) and the de-multiplexer, better known as the Beam Separator Module (BSM). The BCM is located at the input end, while the BSM is located at the output end of the system. A robust and reliable BCM is critical for spatial domain multiplexing technology. This thesis presents a simple and reliable 90-degree off-axis parabolic mirror-based BCM, as well as the relevant mathematical model, simulations, and experiments. This thesis also reviews and analyzes Orbital Angular Momentum (OAM) in spatially multiplexed channels. Finally, this will present a ray theory based simulation software that is specifically designed for SDM channels in an attempt to bridge the void between commercially available simulation tools and SDM applications.