Section 13 - Glossary
05/01/97 REV H
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Section 13 - Glossary
Almanac
The compilation of satellite identification and orbital data used by a GPS
receiver.
Ephemeris data
A uniform measure of data defined by the orbital motion of the planets.
The data is used to calculate exact satellite positions, continually updated
and derived from information relayed to the sensor in each satellite’s data
stream.
Host
The customer system receiving position data from the 8700/8800
series/8900 series.
Selective Availability
(SA)
The intentional degrading by the U.S. Department of Defense of satellite
signals tracked and measured by GPS receivers to determine position,
time, and velocity. SA limits civilian GPS accuracy to about 100 meters,
and velocity accuracy to about one to two knots.
Sentence
A group of data in one of several formats defined by the National Marine
Electronics Association (NMEA). For standard applications, the Northstar
sensors are factory-programmed to output necessary sentences; for cus-
tom applications, the Northstar sensors can be programmed to output
any of several sentence types.
Sferics count
Sferics count is the number of noise impulses that were blanked in the
previous 10-second interval. It’s increased by poor weather conditions
and lightning.
Summary of Contents for 8700
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Page 16: ...Section 2 Introduction PAGE 6 05 01 97 REV H ...
Page 20: ...Section 3 Packaging PAGE 10 05 01 97 REV H ...
Page 32: ...Section 6 GPS beacon combination receivers PAGE 22 05 01 97 REV H ...
Page 46: ...Section 8 Input output configurations PAGE 36 05 01 97 REV H ...
Page 52: ...Section 9 Connector pinouts PAGE 42 05 01 97 REV H ...
Page 76: ...Section 12 8X00 engine monitor program PAGE 66 05 01 97 REV H ...
Page 78: ...Section 13 Glossary PAGE 68 05 01 97 REV H ...
Page 80: ...Section 14 Abbreviations and initialisms PAGE 70 05 01 97 REV H ...
Page 85: ...Index 05 01 97 REV H PAGE 75 ...