Design and Evaluation of Couplers for a Multimode Single Fiber Optical Data Bus.

摘要

The fiber optic couplers designed and evaluated in this thesis are intended primarily for use in aircraft avionics systems, and consist of single strand, multimode fibers with step index profiles. Types of couplers considered are the directional, tee, and star couplers, with emphasis on the latter. Several designs are fabricated and tested, including three kinds of star couplers. The first employed a mixing rod of transparent cement and yielded an average transmission factor of 0.009 (-20.5 dB), with an average insertion loss of -12.83 dB. The second was formed with a solid quartz mixing rod, producing an average transmission factor of 0.003 (-25.2 dB) and an average insertion loss of -18.01 dB. The third star coupler's mixing rod was made by fusing the individual fibers, resulting in an average transmission factor of 0.01 (-20.0 dB) and an average insertion loss of -12.35 dB. After theoretical and experimental comparison between performance efficiencies, the third coupler is recommended as an optimum design for a fiber optic data bus system. (Author)