MSS Configuration

Use this page to configure the receiver to track OmniSTAR satellites or to use Trimble RTX correction services (with xFill technology).

There must be a valid subscription on the receiver before it can use OmniSTAR or Trimble RTX data for positioning.

If OmniSTAR is selected, the following options are available:

Preferred Source of Data – When the OmniSTAR service has been selected, then select either External or Internal. If the receiver is configured to use both internal and external data, it uses the preferred source when both are available:

• External – The OmniSTAR data is derived from an external source such as an NTRIP Client over an internet connection.

• Internal – The OmniSTAR data is derived from the L-Band signal received via an appropriate antenna.

External OmniSTAR Data – Set the receiver to use an external OmniSTAR data stream if available on an Ethernet, NTRIP, serial, Bluetooth, or USB port and then use one of the following modes:

• Don’t Use – Do not use an external source of OmniSTAR data.

• Auto – Tracking is enabled and, if more than one external OmniSTAR service is available, the most precise mode is used.

• Selecting specific services – The following specific services are available for selection if the receiver has an appropriate valid subscription. Selecting one of these modes restricts the receiver from using other external OmniSTAR services:

  • HP only

  • VBS only

Internal OmniSTAR Demodulator – Set the internal OmniSTAR demodulator to the required mode.

• Off – OmniSTAR tracking is disabled.

• Auto – Provides the best solution based on the error estimates. This delays the transition to OmniSTAR HP until the HP solution reports it is better than the VBS solution.

  NOTE – Be careful how you treat VBS; in some locations it is in NAD-83. By default, the receiver provides NAD-83 VBS (in the USA) positions and ITRF2014 for HP. However, you can configure the receiver to transform the NAD-83 VBS positions to ITRF by selecting the following check box.

• Selecting specific services – The following specific services are available if the receiver has an appropriate valid subscription. Selecting one of these modes restricts the receiver from using other internal OmniSTAR services:

  • HP only

  • VBS only

SV name – Select which OmniSTAR satellite beam is to be tracked by the receiver. If you do not know the appropriate OmniSTAR satellite name, select Auto so that the receiver scans for the OmniSTAR satellite whose spot beam is closest to your current location. If the required satellite name does not appear in the list, select Custom and then enter the frequency and bit rate of the required satellite.

Seed with RTK – Select this check box if the primary positioning mode is RTK and you need to use the OmniSTAR solution for short RTK outages. The OmniSTAR engine is seeded with the current RTK Fixed position at a 1 Hz rate. If an RTK Fixed position solution becomes unavailable, the OmniSTAR HP position solution will be used until it is restored. The RTK position is transformed into the OmniSTAR HP datum by using the Datum Offset parameters.

NAD83 - ITRF Transformation – In North America, the OmniSTAR VBS datum is NAD-83, all other OmniSTAR services use the ITRF datum. Enable this feature to transform the VBS positions from NAD-83 to ITRF datum.

Max Data Outage – If the OmniSTAR signal has been lost for the amount of time set in this field, the receiver discards the HP/XP/G2 position or the VBS correction. For OmniSTAR VBS, even though it discards the correction, the firmware still generates VBS positions until the time set in the DGNSS Age of Correction field also expires.

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Fugro SatGuard® Navigation Message Authentication (NMA)

SatGuard is a Fugro subscription service that can be added to a Marinestar G4 subscription for integrity monitoring and spoofing detection.

Navigation Message Authentication (NMA) – Select this check box to authenticate incoming ephemeris data.

Correction Message Authentication (Corr A) – After you select the above check box, you can select this check box to be informed about the authentication status of the Fugro G4 service (clock and orbit) corrections.

Mode – Select one of the following modes:

• Strict – Only authenticated satellites are used in the solution.

• Relaxed – All satellites authenticated at the prior authentication attempt are used in the solution and authentication takes place afterward with a delay, from a few seconds up to around four minutes. Satellites that are not positively authenticated are removed from subsequent solutions.

• Flag – All satellites available are always used in the solution, even if they are not authenticated. A flag is displayed to warn of failed authentication. The Flag mode will never remove any satellites from the solution, only warn that satellites may not be positively authenticated.

Max Authentication Data Outage – If the OmniSTAR signal has been lost for the amount of time set in the Max Authentication Data Outage field, the receiver discards the position or the VBS correction.

For current authentication status, see MSS Status.