Hemisphere GPS S321 - Page 8

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Terms and Definitions (continued)
Term Definition
Ntrip Networked Transport of RTCM via Internet Protocol (Ntrip) is
a protocol for streaming GNSS data over the internet. Ntrip is
most often used to stream RTK or DGNSS corrections over
the internet.
Ntrip Caster Ntrip casters receive data from one or more Ntrip servers and
the data is available to one or more Ntrip clients. Each data
source (Ntrip server) must send the data to a specified Ntrip
mountpoint, and the Ntrip client must specify which
mountpoint to receive data from. This allows multiple base
stations on the same network.
Ntrip Client Ntrip clients receive data from the Ntrip caster and provide
this data
(
often over GSM or serial
)
to the GNSS receiver.
Ntrip Server The Ntrip server sends data from the Ntrip source (base
station
)
to the Ntrip caster.
QZSS Quasi-Zenith Satellite System (QZSS) is a satellite navigation
s
y
stem currentl
y
under development in Japan.
ROX ROX is a Hemisphere GNSS propriety RTK message format
that can be used as an alternative to RTCM3 when both the
base and rover are Hemisphere branded.
RTCM Radio Technical Commission for Maritime Services (RTCM) is
a standard used to define RTK message formats so that
receivers from an
y
manufacturer can be used to
g
ether.
RTK Real-Time-Kinematic (RTK) is a real-time differential GPS
method that provides better accuracy than differential
corrections.
SBAS Satellite Based Augmentation System (SBAS) is a system that
provides differential corrections over satellite throughout a
wide area or re
g
ion.
Signal-to-Noise Ratio Signal-to-Noise Ratio (SNR) is the ratio of the message
content of the si
g
nal a
g
ainst the noise of the si
g
nal.
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.
WAAS Wide Area Augmentation System (WAAS) is a satellite-based
augmentation system (SBAS) that provides free differential
corrections over satellite in parts of North America.