Spectra Precision ProFlex 800 Web Server User Manual
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process, some message data are sampled, which means
that instead of being present in every single message
generated by the base, they will in fact be provided every
x occurrences of the message.
Reconstructing full messages on rover side will however
not tolerate data loss in the transmission. The successful
use of the “Compact” or “Super Compact” formats
therefore demands a very robust data link. In that respect,
a conventional serial line using a cable is more likely to
meet this requirement rather than a radio used in difficult
reception conditions. But on the other hand, using a
compact format seems more especially appropriate to
radio links, owing to their potentially limited data
throughput. So there is some sort of compromise to find
here.
So What Should I Choose? In practice,
Spectra Precision
recommends that you follow these rules:
1. As long as you are not facing any data throughput issue
in your application, using the “Standard” format will
always be the best choice, whatever the data link
media used.
2. Data throughput issues may occur in applications
requiring high output rates (e.g. 10 Hz in heading or
relative positioning applications). In this case,
provided a robust data link is used, you can select
“Compact”, or even “Super Compact” depending on
the data throughput requirement.
Choosing one of these formats when a radio link is
used implies that you have full confidence in the
performance of the radio (good reception conditions,
data loss very unlikely).
3. Using the “Super Compact” format should always be
ruled out for a moving base.
4. Using “Compact” or “Super Compact” to solve the
throughput issues of a radio used in difficult reception
conditions or at range limits, is clearly a bad idea as it
is likely to result in a global malfunctioning of your
application.
Spectra Precision recommends you
reconsider the
implementation of the data link.
There is however a safe operating margin using radio
links since there won’t be any throughput issue
working in “Standard” ATOM format with a radio
operated at 7600 bps.