Telit Wireless Solutions SC872-A, Руководство пользователя

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SC872-A Product User Guide Glossary and Acronyms
1VV0301202 Rev. 6 Page 51 of 53 2018-12-21
SAW : Surface Acoustic Wave filter
Electromechanical device used in radio frequency applications. SAW filters are useful at frequencies up
to 3 GHz.
SBAS : Satellite Based Augmentation System
A system that uses a network of ground stations and geostationary satellites to provide differential
corrections to GNSS receivers. These corrections are transmitted on the same frequency as navigation
signals, so the receiver can use the same front-end design to process them. Current examples are
WAAS, EGNOS, MSAS, and GAGAN .
Server-based Ephemeris prediction data:
Extended Ephemeris (i.e. predicted) data, calculated by a server and provided to the receiver over a
network. It is usually useful for up to 14 days. See AGPS.
TCXO : Temperature-Compensated Crystal Oscillator
Tracking Sensitivity:
The lowest signal level at which a GNSS receiver is able to maintain tracking of a satellite signal after
acquisition is complete.
TTFF : Time to First Fix
The elapsed time required by a receiver to achieve a valid position solution from a specified starting
condition. This value will vary with the operating state of the receiver, the length of time since the last
position fix, the location of the last fix, and the specific receiver design.
A standard reference level of -130 dBm is used for testing.
UART
: Universal Asynchronous Receiver/Transmitter
An integrated circuit (or part thereof) which provides a serial communication port for a computer or
peripheral device.
WAAS : Wide Area Augmentation System
The North American SBAS system developed by the US FAA (Federal Aviation Administration).
Warm Start:
A warm start occurs when a receiver begins operation with known (at least approximately) time and
position, but unknown ephemeris data, typically after being sent a restart command..
See Restart .