Partial & Full MIMO for Orbital Angular Momentum Mode Group Division Multiplexing via Optical Fibers

The use of Orbital Angular Momentum (OAM) of light as a further degree of freedom to encode information has shown great potential in enhancing the capacity transmission and in unleashing the spectral efficiency of optical fibers. Some implications of the use of OAM in mode division multiplexing (MDM) system could degrade the scalability of the system include the complexities and the heaviness of multiple input multiple output MIMO DSP. In this paper, we discuss the MDM system incorporating OAM modes as data carriers. We focus on the employing of MIMO DSP at the receiver side of an OAM-MDM system. Our analysis shows that a small-scale MIMO DSP (i.e. partial blocks) could reduce the computational complexities and minimize the overall system complexity using either time-domain equalization (TDE) or frequency-domain equalization (FDE) approaches.