SX BLUE GPS iSXblue II+ GNSSTM, User Manual

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SXblue Series User Manual 57
2.5.3 Automatic Tracking and Performance
The SXblue Platinum features an automatic mode that allows tracking of the best
spot beam if more than one is available in a particular region. The L-band DGPS
receiver’s frequency does not need to be adjusted with this function. The SXblue
Platinum also features a manual tune mode for flexibility.
The Atlas receiver provides both a lock icon and a BER to describe the lock status
and reception quality. Both of these features depend on a line-of-sight between the
antenna and the geostationary communications satellite broadcasting Atlas
correction information.
The SXblue Platinum antenna is designed with sufficient gain at low elevation
angles to perform well at higher latitudes where the signal power is lower and the
satellite appears lower on the horizon.
The BER number indicates the number of unsuccessfully decoded symbols in a
moving window of 2048 symbols. Due to the use of forward error correction
algorithms, one symbol is composed of two bits.
The BER has a default, no-lock value of 500. As the receiver begins to successfully
acquire the signal, it will result in a lower BER. For best operation, this value should
be less than 150 and ideally less than 20.
2.5.4 Available Services
There are three (3) levels of satellite differential correction services for GNSS
available from Atlas that require a subscription with the company:
o
Atlas Basic: 50 cm 95% (30 cm RMS)
o
H30: 30 cm 95% (15 cm RMS)
o
H10: 8 cm 95% (4 cm RMS)
•
Atlas Global Correction Services for GNSS are being introduced across
a wide range of multi-frequency, multi constellation, and RTK-capable
hardware, available worldwide.
•
Atlas is delivering its correction signals via L-Band satellites or IP address
at accuracies ranging from meter to sub-decimeter levels. With
approximately 200 reference stations worldwide and L-Band satellites
distributing coverage from 75°N to 75°S, all of the earth’s landmass is
covered.
•
Scalable service levels: Atlas is capable of providing virtually any accuracy,
precision and repeatability level in the 5 to 100 cm range.