SEPTENTRIO PolaRx5TR, Reference Manual

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4 SBF Reference
BaseVectorCart
Number: 4043
"OnChange"
interval: default PVT output rate (see 4.1.8)
The
BaseVectorCart
block contains the relative position and orientation of one or more
base stations, as seen from the rover (i.e. this receiver). The relative position is expressed in
the Cartesian X, Y, Z directions.
For highest accuracy, the receiver tries to compute the baseline from rover antenna
reference point (ARP) to base ARP. This requires to compensate for the phase center offset
at both the base and the rover antennas. This is possible if two conditions are met:
• the base station must transmit its antenna parameters in RTCM2 message types 23 and
24 or in RTCM3 message types 1005/1006 and 1007/1008. Older RTCM2 messages and
CMR do not allow phase center offset compensation.
• the base and rover antenna types must belong to the list returned by the command
lstAntennaInfo, overview
. (see the description of the commands
setAntennaOffset
and
lstAntennaInfo
for details).
Accurate ARP-to-ARP baseline is guaranteed only if both bits 0 and 1 of the
Misc
field are
set. Otherwise, centimeter-level offsets may arise because the receiver cannot make the
distinction between phase center and ARP positions. See section 2.5 for a discussion on the
phase center and ARP positions.
The block supports multi-base operation. It contains as many sub-blocks as available
base stations, each sub-block containing the baseline relative to a single base station
identified by the
ReferenceID
field.
Parameter Type Units Do-Not-Use Description
Sync1
c1
Block Header, see 4.1.1
Sync2
c1
CRC
u2
ID
u2
Length
u2
1
byte
TOW
u4
0.001
s
4294967295
Receiver time stamp, see 4.1.3
WNc
u2
1
week
65535
N
u1 Number of baselines for which relative position, velocity and direction
are provided in this SBF block, i.e. number of
VectorInfoCart
sub-
blocks. If
N
is 0, there are no baseline available for this epoch.
SBLength
u1
1
byte Length of one sub-block
VectorInfoCart
... ...
A succession of N
VectorInfoCart
sub-blocks, see definition below
Padding
u1[..] Padding bytes, see 4.1.5
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