CSI Wireless DGPS MAX, Reference Manual

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DGPS MAX Reference Manual
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3.4.1 Tune Modes
The DGPS MAX may be operated in either Automatic or Manual Beacon
tune modes. In Automatic Beacon Search (ABS) mode, the receiver will
identify and tune to the station providing the strongest DGPS signal. In
Manual Tune mode, you specify the frequency to which the receiver will
tune, or select the desired beacon by name from the built-in global listing.
Refer to Figure 5-12 and Section 5.5 to switch between Automatic and
Manual Tune modes using the display and keypad.
3.4.1.1 Automatic Beacon Search (ABS) Mode
When operating using the internal beacon sensor as the source of DGPS
correction information, the DGPS MAX operates in Automatic Beacon
Search (ABS) mode by default, selecting and tuning to the most appropriate
beacon without operator intervention. The DGPS MAX’s internal beacon
receiver uses its two independent beacon channels to identify and lock to
DGPS beacons without interrupting the continuous flow of RTCM data to
the GPS receiver.
ABS mode is ideal for navigation applications over considerable areas,
eliminating the need for operator intervention when transitioning from one
beacon coverage zone to another.
When desired, you may also tune the beacon receiver manually by using
the menu system. This is discussed in Section 5.12.2.
3.4.1.2 ABS Global Beacon Search
When powered for the first time in ABS mode, the DGPS MAX initiates a
Global Search using, examining each available DGPS beacon frequency, and
recording Signal Strength (SS) measurements in units of dB
µ
V/m to the
Global Search Table. The receiver uses these measured values to compute
an average SS, and noise floor, to sort the frequencies in descending order
of SS. The beacon receiver’s two channels cooperatively examine the
frequencies with the highest SS measurements, above the computed noise