Frequently Asked Questions: ANTARIS FAQ

Topic

11	Questions about raw data output (RXM-RAW) of ANTARIS and RINEX conversion.

Questions about raw data output (RXM-RAW) of ANTARIS and RINEX conversion.

Q1: Which message provides raw measurements?
A1: UBX-RXM-RAW.

Q2: How to derive RINEX observables from UBX Message RXM-RAW?
A2: Please refer to this document

Q3: Does u-blox provide a RINEX converter?
A3: Not at this time. There are commercial ones around, which convert UBX-RXM-RAW to RINEX (e.g. from HELENAV Electronic Navigation Equipment, Services and Consultancy in the Netherlands).

Q4: Does u-blox provide GPS real-time and post-processing position determination software?
A4: No. Precise GPS real-time and post-processing position determination software supporting ANTARIS is available from Waypoint Consulting Inc. and VIASAT GeoTechnologies. An open source software for ANTARIS is available at www.precision-gps.org.

Q5: What is the maximum raw measurement update rate (don't confuse this with the position update rate)?
A5: It's currently at 10 Hz (FW versions V3.0 and V3.01).

Q6: We need the measurements from two receivers at exactly the same time. Can we ensure that electrically?
A6: The measurements are taken close to the top-off second. The jitter is in the order of a few milliseconds. But read also the qeustion below.

Q7: How can I extrapolate measurements from multiple receivers to a common timetag?
A7: One needs to extrapolate the carrier phase to the top-of-second by using doppler. This works since the Carrier Phase is nothing else but accumulated dopplers.

Q8: How can I handle receiver clock-slews?
A8: Pseudorange is kept within "sensible" limits. This will result in a clock bias "jump" in the post-processed solution (this is not a problem). In FW version 3.01 and earlier, the carrier phase was also reset. In later versions, the carrier phase will not be reset.

Q9: Does the receiver resolve half-cycle ambiguity?
A9: Yes.

Please refer to the ANTARIS protocol specification for further information.

Further Information

ANTARIS FAQ

/customersupport/faq_antaris/R...
last modified: 30.11.2006

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