Space Division Multiplexing in Multimode Fiber for Channel Diversity in Data Communications

Laguerre-Gaussian mode division multiplexing in multimode fiber using SLMs in VCSEL arrays

“…Fiber Bragg gratings have also been used as mode converters by wavelength control of the desired mode based on the reflection spectra [13] and as mode demultiplexers by adjusting the tilt angle to change the coupling efficiencies into different modes at resonant wavelengths on the transmission spectra [14]. VCSEL arrays have been used for generating various incident wavefronts such as Hermite-Gaussian modes [15,16], donut modes [17,18], Laguerre-Gaussian modes [16,19]. For launching orbital angular momentum (OAM) modes, microscale spiral-phased plates have been inserted directly into the aperture of a vertical-cavity surface-emitting laser (VCSEL) to promote simple alignment to an optical fiber link when launching orbital angular momentum (OAM) modes [20].…”

Mitigation of Atmospheric Turbulences Using Mode Division Multiplexing based on Decision Feedback Equalizer for Free Space Optics

“…Furthermore, the FSO guarantees increasing the capacity by using mode division multiplexing (MDM) technology. MDM is a promising technology [9][10][11] used to transmit the optical signal or light beams in form of modes such as Laguerre-Gaussian mode [12,13], Hermite-Gaussian (HG) mode [14,15], helical-phase mode [16,1718], spot mode, and donut mode [14,16,19] through the transmission channel that leads to expand the capacity . This technology has been used over optical fibre and FSO, where it successfully achieved increasing the data capacity.…”

Radio-over-free space optical space division multiplexing system using 3-core photonic crystal fiber mode group multiplexers

“…Nevertheless, the main challenge for Ro-FSO systems is the performance degradation due to low visibility and turbulence, as optical are not capable of penetrating structures and other obstacles [9,10,21,22]. Space division multiplexing (SDM) is a recent spatial diversity strategy transpired by utilizing different eigenmodes in optical fiber as independent channels to create multiple-input-multiple-output systems [22][23][24][25][26][27]. SDM enables the provision of multiple links during harsh weather conditions in case of failure of any of the links and increases the achievable link distance [28][29][30][31][32][33][34].…”