agps 要怎么实现？ublox 的AssistNow A‑GNSS services 怎么用？？？或者还有什么服务器可以提供agps服务？

http://technicalsearch.iteye.com/blog/2111417
http://www.programgo.com/article/6121540372/;jsessionid=9BC75D8B21DDD8F8E9E0FC0FBE142E0A