ashtech HDS800, Справочное руководство

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Using the Web Server
• All the message types pertaining to a given data format are
listed vertically. These are the following:
• To enable the output of a differential message, you just
need to enter the desired refresh rate (in seconds) for this
message in the corresponding field.
• Leaving a field blank means you don’t want the message
type to be output.
• For ATOM message types, you need to choose between the
different formats available (“Standard”, “Compact” or
“Super Compact”). Basically, the difference between the
three formats lies in the length (size) of the ATOM
messages generated.
Compared to the “Standard” format, “Compact” and
“Super Compact” will produce shorter messages for the
same message content. “Super Compact” will deliver even
shorter messages than “Compact”.
Basically, data compacting is achieved by lowering the
level of redundancy across messages. Through this
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
Format Message types
ATOM
RNX
- Standard (4), Static Base
- Compact (100), Static Base
- Super-compact (101), Static Base
- Standard (204), Moving Base
- Compact (300), Moving Base
RTCM2.3
Message types: 1, 3, 9, 16, 18/19, 20/21, 22, 23, 24, 31, 32, 34,
36
RTCM 3.0
& 3.1
Message types: 1001-1013, 1019, 1020, 1029, 1033
CMR Message types: 0, 1, 2, 3
DBEN Ashtech legacy message