The Design Of Low-cost 1xN Optical Switch

As a new optical access technology, passive optical network (PON) has been widely deployed in recent years. The total traffic amount carried by the whole PON system increased dramatically along with the increasing of the number of laying optical fiber, a wider range of fiber optic cable covered. Once an optical fiber within PON system failure happens, it will cause great losses. Therefore, monitoring and maintenance for the transmission optical fiber in PONs is very crucial.Optical switch is a typical passive optical device and plays a very important role in the optical network maintenance and fault-point monitoring system. This paper studied on two kinds of low-cost 1xN optical switch, which can be applied in a new fiber optic cable monitoring system for PON.These optical switches feature low cost, small in size and multi-channel operation, etc.Firstly, the categories and characteristics and progresses of various optical switch are reviewed; the background of this project is introduced——these low cost optical switches are designed and used in a new solution for PON optical fiber monitoring; and their application in this new PON fiber optic cable monitoring system is pointed out.Secondly, two kinds of optical switch are studied in this thesis.Based on the theoretical analysis of the fiber coupling losses, the first kind of optical switch is realized by moving optical fiber positioned in the V-slot, its corresponding optical design and electronic circuit design are given, the final packaging and performance testing of this optical switch samples are discussed. The test results show that this kind of optical switch has reach all expected design goals.The second kind of optical switch based on the operation principle of rotating wedge mirror is realized by changing the deflection angle of wedge mirror, so that the output beam arrives at the desired output.port.Then, combined with their applications in the new optical fiber monitoring solution for PONs,the design and operation principle of optical switch control board with low-power consumption is studied in detailed. Finally, a summary and prospects of this thesis are given.