发明申请
- 专利标题: Unassisted indoor GPS receiver
- 专利标题(中): 无人值守的室内GPS接收器
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申请号: US11324144申请日: 2005-12-29
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公开(公告)号: US20070152878A1公开(公告)日: 2007-07-05
- 发明人: Chi-Shin Wang , Zongde Qiu , Shridhara Kudrethaya , Jun Mo
- 申请人: Chi-Shin Wang , Zongde Qiu , Shridhara Kudrethaya , Jun Mo
- 专利权人: Centrality Communications, Inc.
- 当前专利权人: Centrality Communications, Inc.
- 主分类号: G01S5/14
- IPC分类号: G01S5/14
摘要:
The present invention provides GPS receivers capable of tracking very weak GPS signals particularly in an indoor environment without assistance from an external server or a network. In a preferred embodiment, a GPS receiver initially acquires and locks onto GPS satellite signals to compute receiver position outdoors. The GPS receiver then tracks at least one satellite signal indoors to maintain acquisition parameters for quick acquisition of GPS signals. To save power, the receiver automatically goes to the sleep state and periodically wakes up, i.e., powers up, to maintain the at least one satellite signal tracking. During the wakeup state, the receiver collects ephemeris data from the at least one satellite signal when the ephemeris data needs to be updated for quick acquisition of GPS signals.
公开/授权文献
- US07570208B2 Unassisted indoor GPS receiver 公开/授权日:2009-08-04