Raka Biswas

Simultaneous transmission of two channels operating at the same wavelength in standard multimode fibers

Spatial domain multiplexing is a novel multiplexing technique providing a method to transmit multiple channels of same wavelength inside an optical fiber. Two such analog channels on optical fibers for LAN applications are reported.

SDM propagation model for multiple channels using electromagnetic theory and vortex analysis

Spatial Domain Multiplexing (SDM) is a novel technique in optical fiber communications. Single mode fibers are used to launch Gaussian beams of the same wavelength into a multimode step index fiber at specific angles. Based on the launch angle, the channel follows a helical path. The helical trajectory is explained with the help of vortex theory. The electromagnetic wave based vortex formation and propagation is mathematically modeled for multiple channels and the results are compared against experimental and simulated data. The modeled output intensity is analyzed to show a relationship between launch angle and the electric field intensity.

CAD model for co-propagating spatially multiplexed channels of same wavelength over standard multimode fibers

Spatial Domain Multiplexing (SDM) is a novel technique that allows co-propagation of two or more optical communication channels of the same wavelengths over a single strand of optical fiber cable by maintaining spatial separation between the channels. Spatial multiplexer known as the beam combiner module (BCM) supports helical propagation of light to ensure spatial separation between the channels. It is inserted at the input end of the system. Spatial de-multiplexing is achieved by a unit named beam separator module (BSM). This unit is inserted at the receiving end of the system and it routes the optical energy from individual channels to dedicated receivers. Spatially multiplexed channels exhibit negligible crosstalk. The bandwidth of the fiber optic systems employing SDM technique increases by multiple folds. CAD model of a beam combiner module for a two channel system using commercially available simulation tools is presented here. Simulated beam profile of the output is compared to the experimental data.

CAD Analysis of Four Co-Propagating Spatial Domain Multiplexed (SDM) Channels of Same Wavelength in Optical Fibers

A four channel spatially multiplexed optical system has been designed using commercially available CAD software. Two dimensional intensity plot and three dimensional beam profiles with CAD simulated output data are presented in this paper.

Beam Profile of Two Simultaneously Propagating Channels of Same Wavelength in Step Index Multimode Fibers

Spatially multiplexed channels of exactly the same wavelength can be transmitted simultaneously over a single strand of multimode fiber. Experimental setup, screen projection of output and beam intensity profiles at the exit end is presented.

CAD simulated and experimental beam profile analysis of single-mode tapered fibers for optical bandwidth enhancement applications

Most developments in data transfer techniques are incremental by nature and the goal of increasing total capacity in optical communications and networking requires new concepts for basic transmission media. The transmission data rates can only be enhanced by introducing new modulation and multiplexing techniques. In this paper different single mode tapered fiber waveguides are used to design a Spatial Multiplexer Unit (SMU) for a novel optical fiber multiplexing technique called the Spatial Domain Multiplexing (SDM) that allows co-propagation of two or more channels of exactly same wavelength without interfering with each other. This paper also presents a CAD model for the SMU and then compares the output beam profiles from different single mode tapered fibers to determine the optimum geometry for the SMU. Finally experimental and simulated beam profiles for the SMU are presented.