Design And Implementation Of Communication Lines Maintenance System Based On GIS

With the increasing popularity of light-guide fiber communications , the light-guide fiber net is becoming larger and larger day by day. The difficulty to maintain communication lines is greatly increased compared to previous years. So urgently,we need a systematic, scientific and efficient management methods to replace the traditional management.Geographical Information System(GIS, in short), is a kind of computerized database management system to obtain, store, retrieve, analyze and display spatial positioning data.This system could show the elements in large geographical area and the attribute information related to these elements.And also include a series of auxiliary functions such as spatial query, spatial analysis.The scalability of GIS is Flexible too, users can add functional modules according to their own needs.These characteristics are just in line with the replacement need of fiber optic communication line management and maintenance methods.Author according to the accumulation of daily maintenance and management experience in fiber-optic cables, analysis the systematic needs, defined the system functions and structure.Using GIS as a platform, integrate of GIS technology, GPS technology and database technology, achieved the collection, entry, storage, management of spatial data,and presented these this data to users visually.Using the attribute informations and multimedia technology, provide the necessary data to support the fiber-optic cables maintenance.The system also has several powerful aids such as: fault location function, the best path analysis function, factor query function, and GPS navigation function.Through careful analysis and comparison, system uses Microsoft's Visual Basic 6.0, as a programming tool, MapInfo's MapX for the secondary development platform, Oracle8i for the database. In the process of system building, relate to the following content:(1) the basic theory and the development direction of GISGIS is composed of five parts that are hardware,software, data, person and method. Its main function is to transform some form of data analysis, processing, integration, in order to show them a different data format.With hardware,network and database technology's development, GIS is in the way of networking, data warehousing, three-dimensional-oriented and component-based.(2) the development mode and comparison of various types of secondary development platform of GISThe system we did is application-oriented that has three ways to Achieve which is independent development, purely secondary development and integrated secondary development.And the third method is most popular,because it reduce the workload of developers,increase the reusability of program,has a friendly interface,has a personality appearance, greater efficiency, more powerful database features,better robustness and easyer to be transplanted.(3) systematic analysis consistent with software engineering methodsAccording to the author's experience and the needs of work,the system's basic functions are: map operation,communication lines information management, query capabilities, spatial analysis, and system management;the specific functions are: fault location, patch panel information display, three-dimensional display and Geometric analysis.(4) Data inputThe collection and input of fiber-optic cables and the surrounding geographical elements of the spatial data is the main work of the data input.The vector map has been prepared and the collection of spatial data uses GPS technology and multimedia technology ,which can show the object accurately and comprehensivly.The format conversion of spatial data collected from other GIS is also important,we can use MapInfo's own converter to converse these different format.(5) the unified management of spatial data and attribute data,and on this basis, design spatial data structure and attribute databaseIn this system, spatial data and attribute data's management is separated. Spatial data is preserved as files operateing with GIS tools. Attribute data is managed with relational database. And then correspond spatial data and attribute data.(6) using MapX To achieve map editor, pixel management, layer management,——the basic functions of GIS in VB environment(7) With some external devices, locate the point of failure quickly and accuratelyThe processing of fault location is:find the point that optical power get down seriously with OTDR,get the distance of the failure point from the station,with the help of marked points that posit with GPS,we can find the failure point exactly.(8) achieve query of attribute information to spatial data and spatial data to attribute informationIn GIS,it is necessary to find the information through the known spatial object;and it's also necessary to find the spatial object through the known information.With the link of spatial database and attribute database,we achieve this objective.(9) using Dijkstra algorithm, achieve the shortest path analysis from the maintenance center to the point of failureWe can get the shortest way with the classical algorithm - Dijkstra Algorithm,then analysis traffic and other factors,using the database,so people can find the best way quickly.(10) GPS NavigationThe system uses car GPS, receive time, longitude, latitude though VB controls, show the location of the car in the map window.And we can set the right way in the system to prevent the car go to the wrong way with warning.