发明名称 |
PROVIDING TIME SYNCHRONIZATION TO A GPS LOCATOR |
摘要 |
A method and system for knowing positioning system standard time at a mobile unit with respect to a system, such as the Global Positioning System, when normal, direct measurement may be impracticable owing to low signal-to-noise ratio, by calibrating the timing signal of an available communication network, such as a cellular telephone transmission network (610, 615). A time reference is set for the communcation network with respect to the positioning system at a time when an adequate signal-to-noise ratio prevails and the offset of a timing event in the communication network control signal measured by means of the mobile unit's internal clock may be determined (620, 625). Subsequent times are measured with respect to this time reference by using the internal clock to measure time intervals therefrom.
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申请公布号 |
WO0176285(A1) |
申请公布日期 |
2001.10.11 |
申请号 |
WO2001US09591 |
申请日期 |
2001.03.26 |
申请人 |
CELLGUIDE LTD.;FRIEDMAN, MARK, M.;NIR, JOSEPH;SHAYEVITS, BARUCH;COHEN, HANOCH |
发明人 |
NIR, JOSEPH;SHAYEVITS, BARUCH;COHEN, HANOCH |
分类号 |
G01S19/48;G01S1/00;H04W4/02;H04W56/00;H04W64/00;(IPC1-7):H04Q7/20 |
主分类号 |
G01S19/48 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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