ashtech HDS800, Reference Manual

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Using the Web Server
throughput. So there is some sort of compromise to find
here.
So What Should I Choose? In practice, Ashtech
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 misfunctioning of your
application. Ashtech 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.
The table below gives average data throughput figures ( in
bytes/sec ) for different GNSS signals and three message
types (RTCM-3 given as reference).
Protocol/
Scenario
GPS+GLONASS
L1/L2
GPS+GLONASS
L1 (L1CA only)
GPS L1/L2
ATOM RNX
(SCN,4)
317 205 193
ATOM RNX
(SCN,100)
159* 140* 98*
ATOM RNX
(SCN,101)
86* 75* 70*
RTCM-3 338 (MT 1004,1012) 214 (MT 1002,1010) 202 (MT 1004)