C-Nav 2050, Руководство пользователя

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2050 User Guide
RCP a NavCom Technology, Inc. proprietary processing technique in which carrier phase
measurements, free of Ionospheric and Troposphere effects are used for navigation.
Real-Time Kinematic ( RTK ) a GPS system that yields very accurate 3D position fixes immediately
in real-time. The base station transmits its GPS position to roving receivers as the receiver
generates them, and the roving receivers use the base station readings to differentially correct their
own positions. Accuracies of a few centimeters in all three dimensions are possible. RTK requires
dual frequency GPS receivers and high speed radio modems.
reference station a reference station collects GPS data for a fixed, known location. Some of the
errors in the GPS positions for this location can be applied to positions recorded at the same time by
roving receivers which are relatively close to the reference station . A reference station is used to
improve the quality and accuracy of GPS data collected by roving receivers .
RHCP Right Hand Circular Polarization used to discriminate satellite signals. GPS signals are
RHCP.
RINEX (Receiver Independent Exchange) is a file set of standard definitions and formats designed
to be receiver or software manufacturer independent and to promote the free exchange of GPS
data. The RINEX file format consists of separate files, the three most commonly used are: the
observation (.YYo) file, the navigation (.YYn) file, and the meteorological (.YYm) files; where YY
indicates the last two digits of the year the data was collected.
rover any mobile GPS receiver and field computer collecting data in the field. A roving receiver’s
position can be differentially corrected relative to a stationary reference GPS receiver or by using
GPS orbit and clock corrections from a SBAS such as StarFire

.
roving receiver see rover .
RTCM - (Radio Technical Commission for Maritime Services) a standard format for Differential GPS
corrections used to transmit corrections from a base station to rovers . RTCM allows both real-time
kinematic ( RTK ) data collection and post-processed differential data collection. RTCM SC-104
(RTCM Special Committee 104) is the most commonly used version of RTCM message.
RTK see Real-time kinematic .
RTG Real Time GIPSY, a processing technique developed by NASA’s Jet Propulsion Laboratory to
provide a single set of real time global corrections for the GPS satellites.
S/A see Selective availability .
SBAS (Satellite Based Augmentation System) this is a more general term, which encompasses
WAAS , StarFire

and EGNOS type corrections.
Selective Availability (S/A) deliberate degradation of the GPS signal by encrypting the P-code .
When the US Department of Defense uses S/A , the signal contains errors, which can cause
positions to be inaccurate by as much as 100 meters.
Signal-to-Noise Ratio ( SNR ) a measure of a satellite’s signal strength.
single-frequency a type of receiver that only uses the L1 GPS signal. There is no compensation
for ionospheric effects.
SNR see signal-to-noise Ratio.
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