由国外的一个著名的geonetwork修改而来，包含installer文件夹供用户直接安装查看效果以及完整的源码，可支持各类卫星元数据标准的索引及查询，由Java编写，功能强大。-from abroad a famous GeoNetwork changes come, folder contains installer for users installed directly View results and integrity of the source code, satellite ca

对GPS初学者来说，可以直观的查看GPS卫星分布以及进行模拟结算用户位置-Pairs of GPS for beginners, this may be an intuitive view to simulate GPS satellite distribution and settlement of user location

Gpredict is a real-time satellite tracking and orbit prediction application. It can track an unlimited number of satellites and display their position and other data in lists, tables, maps, and polar plots (radar view). Gpredict can also predict the