Javad OMEGA, Руководство пользователя

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Description and Operation
Introduction
OMEGA is the most advanced GNSS receiver. It does
not include integrated antenna and controller, based
on our new 864 channel chip, equipped with the inter-
nal 4G/LTE/3G card, easy accessible microSD and mi-
croSIM cards. It is suited for applications like machine
control and in marine and avionics applications.
Adding GrAnt and VICTOR-LS makes a complete
RTK systems. It is well suited for monitoring and net-
work stations.
Figure 1.
OMEGA
OMEGA can receive and processes multiple signal
types (including the latest GPS C/A, P1, P2, L2C (L+M);
GLONASS C/A, L2C, P1, P2; SBAS L1) improving the ac-
curacy and reliability of your survey points and posi-
tions, especially under difficult jobsite conditions.
Several other features, including multipath miti-
gation and common tracking, provide under-canopy
and low signal strength reception. The OMEGA receiv-
er provides the functionality, accuracy, availability,
and integrity needed for fast and easy data collection
.
When calculating an absolute position, a stationary
or moving receiver determines its three-dimensional
position with respect to the origin of an Earth-Center
Earth-Fixed coordinate system. To calculate this po-
sition, the receiver measures the distance (called
pseudoranges) between it and at least four satellites.
The measured pseudoranges are corrected for clock
differences (receiver and satellites) and signal prop-
agation delays due to atmospheric effects. The posi-
tions of the satellites are computed from the ephem-
eris data transmitted to the receiver in navigation
messages. When using a single satellite system, the
minimum number of satellites needed to compute
a position is four. In a mixed satellite scenario (GPS,
GLONASS, Galileo), the receiver must lock onto five or
more satellites to account for the different time scales
used in these systems and to obtain an absolute po-
sition.
Achieving quality position results requires the fol-
lowing elements:
Accuracy – The accuracy of a position primari-
ly depends upon the satellite geometry (Geometric
Dilution of Precision, or GDOP) and the measurement
(ranging) errors.
– Differential positioning (DGPS and RTK) strong-
ly mitigates atmospheric and orbital errors, and
counteracts Selective Availability (SA) signals the US
Department of Defense transmits with GPS signals.
– The more satellites in view, the stronger the sig-
nal, the lower the DOP number, the higher position-