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Questionnaire concerning GLONASS biases:
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Your institution:
Contact email address(es):

The GLONASS clock corrections you generate are consistent to:
[x] pseudorange
[x] carrier phase
Please mark both fields if indicated.

Clock corrections are generated at intervals of: 30 seconds


Handling of GLONASS interfrequency code biases (for ionosphere-free LC):
[x] one bias parameter for each station and satellite combination/pair
[ ] one bias parameter for each station and frequency channel
combination/pair
[ ] other configuration:
Time resolution: one value per day


Description of datum definition (or reference) for GLONASS code biases:
Currently no fixed datum definition. A constraint on the bias estimates of 0.1 microsecond is applied (relative to an apriori value coming from a pseudo-range based preprocessing
In the next NAPEOS version (3.7) we will have the ability (and will start using) a "zero mean" constraint over all the ISBs (or possbily a subset of stations).

How many conditions/constraints are imposed for the bias datum definition? None except the general constrain of 0.1 microsecond on all ISBs


How do you select GLONASS code observable types (to be used for a specific
station) if P1 and C1, or P2 and C2 are available?

1) Firstly in our processing C2 is completely ignored. So observation existing of P1 and C2 or C1 and C2 are NEVER used. This holds both for GPS and GLONASS
2) Secondly P1 is preferred but if unavailable C1 is used. C1 observations are "converted" to P1 using the CC2NONCC tool. Not 100% sure how well/correct that works for GLONASS. For GPS it should be OK.


Do you generate GLONASS clock corrections on a regular/operational basis?
[X] Yes
[ } No, but test results (in clock-RINEX) would be available for:


Recommendations for PPP users of your GLONASS clock product: Use them, it really improves your solutions, especially kinematic solutions! Be sure to estimate an ISB for each rec-sat pair for the GLONASS observations.


Do you have corresponding GLONASS bias results available (in ASCII form)?
[X] Yes. From our reprocessing (initial repro2 run) we have the biases available from 1.1.2009 onwards.
[ ] No

Are there any specialties concerning your GLONASS clock product? Possibly "best in class" (ha, ha, just for fun)


Extra question: Do you have experience with GLONASS ambiguity resolution?
[ ] No
[X] Yes, please specify: Several attempts have been made with different strategies. However, very few ambiguities resolved and no noticeable positive effects so far. But we have not yet given up hope.....and CDMA for GLONASS is coming.....


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