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Introduction to
Multi-Operating
Mode
The SP90m is a multi-application GNSS receiver, making it
possible to use different operating modes simultaneously.
The limitation to that feature is very simple to understand:
The maximum number of baselines the SP90m can calculate
simultaneously is 3
. The capability for the SP90m to support
several operating modes simultaneously is simply derived
from that statement.
NOTE: Working in a Trimble RTX mode does not “consume” a
baseline, which means that the above statement would be
more accurate if we said, “The maximum number of baselines
the SP90m can calculate simultaneously is 3 + RTX”.
The consequences of this rule are as follows:
• In single-antenna configuration:
– In Hot Standby RTK, you can configure the receiver to
use up to three independent correction sources (=
three baselines), thus making it possible to have up to
two different backup position solutions available in
case the first source of position solution fails.
–
In Hot Standby RTK + Relative RTK, you can only set
two independent correction sources (= two baselines),
to have a backup position solution available in case the
first source of position solution fails. The third baseline
is dedicated to the Relative RTK mode.
• In a two-antenna configuration, the heading mode may be
combined with all of the existing rover modes:
–
Autonomous
–
RTK
–
Hot Standby RTK
–
RTK + Relative RTK
–
Only Relative RTK
–
Dual RTK
–
Dual Relative RTK
However, in Hot Standby RTK, there can only be two
independent sets of corrections used (not three because
one baseline is dedicated to computing heading).
Besides, the rover and moving base modes can be run
simultaneously. To make this work, you should first configure
the receiver as a rover, then as a moving base (and not the
other way round). That way, while base corrections will be
generated and delivered via your programmed output
messages, the receiver will continue to compute RTK
positions for its own location provided the required external
corrections continue to enter the receiver.
