Thales MobileMapper Beacon, Руководство пользователя

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Monitoring Reception Performance
Beacon reception performance is described by a signal to
noise ratio (SNR) number. Essentially what this number in-
dicates is how much the signal 'peaks' above the noise floor.
A taller signal would mean better reception performance
than a shorter signal above the noise floor. The SNR is mea-
sured in decibels (dB).
The following table describes reception performance based
on the SNR indicator.
Beacon Interference
The signals transmitted from Coast Guard beacon stations
are very weak and can be jammed by noise emitted from
electronics. All electronics emit some type of radio noise.
Depending on the amplitude and frequency bands that they
emit, it has the potential to interfere with beacon reception.
There are other sources of noise, such as power lines, engine
electronics of vehicles, power transformers, and the like.
The MobileMapper Beacon system is able to provide diag-
nostic information to the DGPS Configuration application
that you can run on your PC or on the MobileMapper CE
system. This utility can allow you to monitor the current re-
ception performance of the MobileMapper Beacon system.
This will tell you how well it's receiving the signal compared
to the amount of noise present in the environment.
SNR Receiver Description Approximate Data Throughput
>25 Excellent 100% data throughput
20 to 25 Very Good 100% data throughput
15 to 20 Good Good data throughput up to 100%
10 to 15 Moderate Moderate to good data throughput
7 to 10 Intermittent Low data throughput
<7 No Lock No data throughput