SEPTENTRIO PolaRx5TR, Справочное руководство

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2 Operation Details
file, the receiver cannot make the distinction between phase center and ARP, and the position
accuracy is slightly degraded, especially in the height component.
The point to be positioned is the "marker" (see Figure 2-3). The offset between the ARP and
the marker is a function of the antenna monumentation. It must be measured by the user
and specified with the
setAntennaOffset
command.
The absolute position reported in the
PVTCartesian
and
PVTGeodetic
SBF blocks is al-
ways the marker position.
In DGPS or RTK modes, the receiver needs to know the type of antenna used at the base
station in order to properly compensate for the phase center variation at the base. This
information is typically included in the correction stream received from the base station.
The base-to-rover baseline coordinates in the
BaseVectorCart
and
BaseVectorGeod
SBF blocks is from ARP to ARP unless the receiver is not able to properly compensate for the
phase center variation at base or rover. Refer to the description of the
BaseVectorCart
SBF blocks for details.
2.5.2 Antenna Effects in Base Mode
Phase center compensation always happens at the rover side. The base station sends un-
compensated measurements in its differential correction messages, together with its ARP
position and antenna type. The antenna type information allows the rover to apply the ap-
propriate phase center compensation to the base measurements.
When setting up a base station, it is therefore important that the coordinates entered with
the
setStaticPosGeodetic
or the
setStaticPosCartesian
commands refer to the
ARP. The coordinates are encoded without change in the relevant differential correction mes-
sages. The antenna type must be provided with the
setAntennaOffset
command.
2.6 Galileo OSNMA
The receiver supports Galileo Open-Service Navigation Message Authentication (OSNMA),
when enabled with the
setGalOSNMAUsage
command.
The authentication status is reported in the
GALAuthStatus
SBF block. The main steps
involved in OSNMA authentication are summarized below.
1. The receiver may still need to gather initial information (e.g. public keys) from the
Galileo satellites before being able to launch its authentication function. The initializa-
tion progress is reported in % in the
OSNMAStatus
field of
GALAuthStatus
. Once
100% is reached, all necessary information is available. The process of information
gathering can take up to a few minutes, but is typically only needed once as the
receiver stores the data in its non-volatile memory.
2. After initialization, the authentication process starts, indicated by the
OSNMAStatus
field of
GALAuthStatus
changing to
authenticating
. Roughly a minute after this
transition, satellite authentication results are expected to become available. The
ActiveMask
and
AuthenticMask
fields indicate for which satellites authentication
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