A J2ME based digital map system

The paper descrihes the design and implemenfatiun of a vector graphic based digi~al Map system that can be displayed on plaffivms that .support J2ME (Java 2 Micro Edition). The digifal map ir?formation is encoded in the GDF (Geographic Data File) vector graphic fbrmat utilizins GPS coordinators (1.7 r+rence.s. and is stored in a dutuhase on the Map Server. A portable device (notehook, PDA. ond other mohile devices) conpled with a GPS receiver and wireless LAN con reyue.sf for the map irlformation ut itr immediate vicini@ hv sending i ts GPS coordinates to the Map server. The server then retrieves the relevant section (Jf the map. /ranslates the detail into U XML-hosed Qrmat. and t?ansfer.s the infirmation to the display device that support J?ME standord. The XML data contains not onlv the map information: i t o1,so contains the relevant at/rihrrte.s of the ohjects ,found in the map. Using this .sy.stem. map can be generated on-demand,fram the digital database in real time and streumed to the portahle device.7 as it is moved around. Index Terms GDF, JZME, Vector Graphics, XML.