Extract And Publish The Incremental Information Of The Road Network In The Electronic Map Update

In recent years, along with the rapid promotion of mobile phone hardware and ceaselessly upgrade of software, the multifunctional intelligent mobile phone has gradually become the mainstream consumer products in mobile phone markets, along with the large-scale coverage of the3G wireless network," mobile location services" has become a focus, in which navigation electronic map has a more extensive application. Navigation electronic map has a high level of requirements to map data in the reality and accuracy, butcurrently the timeliness of the location service of spatial information is unsatisfactory, data update rate is far behind of city construction, and the nation has not yet taken a large-scale investment in the electronic map update, together with the electronic map market is not enough transparent, the problem of real-time updating of electronic map cannot be solved effectively, these problems make electronic map has become a bottleneck in the development of location service market.In view of the current problems, incremental updating of electronic map is introduced to be the solution of rapid data updating of navigation electronic map, it is consistent with the demand of most the navigation electronic map users and service providers. Incremental data update mode, namely updating the master database immediately once changeswere found, and continuously provide to the user, compared to the traditional off-line version updating, incremental updatinghas some advantages as smaller data transmission amount, lower cost, easy to be updated. At present the studies on incremental online updatemainly focus on the incremental information accurate extraction, incremental information organization and expression, update operator design, update operation data integrity and topology maintenance etc.The main content of this paper includes the following aspects: incremental information recognition and extraction based on the object matching method, generation of incremental update files, focus on the threshold settings in the progress of object matching, and the results are verified by experiment; In response to the powerless of complex data operation and topology error correction, we added topology error correction information in incremental update files in the server side, simplified the client update process, improve the update efficiency and accuracy; Incremental update files organization and expression was done based on SVG format, which reducing the update file transmission data quantity and the data updating cost; Exploiting these key technologies we developed client data update system based on the J2ME platform, and validated the feasibility of the solution.