Invention Grant
US5654718A GPS receiver device and method for calibrating a temperature
uncompensated crystal oscillator
失效
GPS接收机装置和校准温度无补偿晶体振荡器的方法
- Patent Title: GPS receiver device and method for calibrating a temperature uncompensated crystal oscillator
- Patent Title (中): GPS接收机装置和校准温度无补偿晶体振荡器的方法
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Application No.: US751385Application Date: 1996-11-19
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Publication No.: US5654718APublication Date: 1997-08-05
- Inventor: Lawrence W. Beason , Ronald T. Chinnery , Stephen Davis , Jay Dee Krull
- Applicant: Lawrence W. Beason , Ronald T. Chinnery , Stephen Davis , Jay Dee Krull
- Applicant Address: KS Olathe
- Assignee: Garmin Corporation
- Current Assignee: Garmin Corporation
- Current Assignee Address: KS Olathe
- Main IPC: G01S1/00
- IPC: G01S1/00 ; G01S5/14 ; G01S19/19 ; G01S19/23 ; H03L1/02 ; G01S5/02 ; G01J5/00
Abstract:
A device and method for compensating a crystal oscillator that is not electrically compensated over its operable temperature range. A GPS receiver device stores in memory data indicative of the actual offset frequency of oscillation of the crystal over its operable temperature range. The first time the device is activated, the temperature at the crystal is sensed and data, stored in memory, indicative of the specified frequency offset of the crystal at the sensed temperature is retrieved, and used to control the receiver.backslash.decoder. When the receiver locks onto a sufficient number of satellites to calculate its two-dimensional location, the actual frequency offset of the crystal is calculated and stored in memory. Repeated use of the receiver device permits a database of actual frequency offset data of the crystal, over its operable temperature range to be stored. Subsequent uses of the device permit retrieval of this data for use in locking the receiver onto satellite signals. If such data is not available, the device uses the average offset data at the given temperature. The device further adjusts the offset data originally retrieved or computed until the receiver locks onto the desired signal.
Public/Granted literature
- US5165832A Removable B-nut retaining wire Public/Granted day:1992-11-24
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