Javad TRIUMPH-1M, Руководство пользователя

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Description and
Operation
INTRODUCTION
The new TRIUMPH-1M receiver inherits the best
features of our famous TRIUMPH-1. Based on our
new 864 channel chip, equipped with the internal 4G/
LTE/3G card, easy accessible microSD and microSIM
cards, includes “Lift & Tilt” technology. (Fig. 1).
Figure 1. TRIUMPH-1M
TRIUMPH-1 can receive and processes multiple sig-
nal types (including the latest GPS C/A, P1, P2, L2C
(L+M); GLONASS C/A, L2C, P1, P2; SBAS L1) improv-
ing the accuracy and reliability of your survey points
and positions, especially under difficult jobsite con-
ditions.
Several other features, including multipath miti-
gation and common tracking, provide under-canopy
and low signal strength reception. The TRIUMPH-1
receiver provides the functionality, accuracy, avail-
ability, 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-
ing accuracy.
Availability – The availability of satellites affects
the calculation of valid positions. The more visible
satellites available, the more valid and accurate the
position. Natural and man-made objects can block,
interrupt, and distort signals, lowering the number
of available satellites and adversely affecting signal
reception.
Integrity – Fault tolerance allows a position to have
greater integrity, increasing accuracy. Several factors
combine to provide fault tolerance, including:
– Receiver Autonomous Integrity Monitoring (RAIM)
detects faulty GNSS satellites and removes them from
the position calculation.