Nguyen Minh Hoang creator Lochmann, S. Chairperson Erke, Tapio J. Examination Committee Sharma, A.B. Examination Committee Finnish International Development Agency (FINNIDA), Finland Scholarship donor text series technical report th Bangkok Asian Institute of Technology 1993 continuing eng 77 leaves + 1 online resource Metallic cables have been used in local subscriber loop systems since the introduction of very first telecommunication system. It would appear logical to introduce fiber optic systems into subscriber networks as a natural consequence of their successful introduction into trunk networks. This study presents a design and construction of an optical-fiber local loop for ISDN basic access interface. Two optical systems, which use two-level and tri-level codes for transmitting through the fiber, were designed and implemented with a consideration in comparison with their effective cost and performance. An optical link was set up between an ISDN subscriber and NT1 of the DX-220 ISDN exchange. In addition, an CD-Player laser diode and techniques for coupling it to optical fiber were investigated. It was shown that the fiber was most suitable to be implemented at the S-interface of basic access ISDN and with ternary line coding scheme was employed for optical signal transmission. A research study report submitted in partial fulfillment of the requirement for the degree of Master of Engineering, School of Engineering and Technology Research Studies Project Report (M.Eng.) - Asian Institute of Technology, 1993 Telecommunication systems Optical fibers Asian Institute of Technology. http://203.159.5.9/ait-thesis/detail.php?q=B16087 http://203.159.5.9/ait-thesis/detail.php?q=B16087 121095 20260818090058.0