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Terms and Definitions
The following table lists the terms and definitions used in this document
Term
Definition
DGPS/DGNSS
Differential GPS/GNSS refers to a receiver using Differential
Corrections.
Firmware
Firmware is the software loaded into the receiver that controls
the functionality of the receiver and runs the GNSS engine.
GNSS
Global Navigation Satellite System (GNSS) is a system that
provides autonomous 3D position (latitude, longitude, and
altitude) along with very accurate timing globally by using
satellites. Current GNSS providers are: GPS, GLONASS and
Galileo. BeiDou is expected to have global coverage by 2020.
GPS
Global Positioning System (GPS) is a global navigation
satellite system implemented by the United States.
NMEA
National Marine Electronics Association (NMEA) is a marine
electronics organization that sets standards for
communication between marine electronics.
RTCM
Radio Technical Commission for Maritime Services (RTCM) is
a standard used to define RTK message formats so that
receivers from any manufacturer can be used together.
SBAS
Satellite Based Augmentation System (SBAS) is a system that
provides differential corrections over satellite throughout a
wide area or region.
Signal-to-Noise Ratio
Signal-to-Noise Ratio (SNR) is the ratio of the message
content of the signal against the noise of the signal.
Subscription
A subscription is a feature that is enabled for a limited time.
Once the end-date of the subscription has been reached, the
feature will turn off until the subscription is renewed.