Questionnaire concerning of biases for undifferenced ambiguity resolution:
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Your name and institution:
Jianghui Geng, NGI, University of Nottingham (now at: SOPAC, SIO)
Norman Teferle, University of Luxembourg

Contact email address(es):
jhgeng1982@gmail.com
norman.teferle@uni.lu

Primary reference/paper for your approach (URL address or email attached):
Ge, M., G. Gendt, M. Rothacher, C. Shi, and J. Liu (2008), Resolution of GPS carrier-phase ambiguities in Precise Point Positioning (PPP) with daily observations, Journal of Geodesy, 82(7), 389-399.
Geng, J., X. Meng, A. H. Dodson, and F. N. Teferle (2010), Integer ambiguity resolution in precise point positioning: method comparison, Journal of Geodesy, 84(9), 569-581.

List of bias types considered and their temporal resolution:
wide-lane uncalibrated phase delays (daily estimate)
narrow-lane uncalibrated phase delays (at 15 minutes or pass-period for a satellite pair)

Clock corrections are generated at intervals of:
at each epoch, depends on the sampling rate of observations.

Ambiguity resolution for:
[X] undifferenced observations
[ ] between-satellite observations
[ ] other:
We can now fix undifferenced ambiguities directly without forming single difference between satellites.

How do you select GPS code observable types (to be used for a specific station)
if P1 and C1, or P2 and C2 are available?
P1 and P2 always. If there isn't P1, C1 will be transformed to P1 using cc2noncc. 

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


Recommendations for PPP users of your integer phase clock product:
the UPD are for a specific satellite-pair. the user needs to pair the same satellites.
UPDs can be assimilated into satellite clocks to form integer clocks.

Do you have corresponding bias results available (in ASCII form)?
[ ] Yes
[X] No
Do you mean UPD estimates?

Are there any specialties concerning your integer phase clock product?
We don't generate integer clocks at all.

Extra question: Do you have experience/plans in extending your approach to
GLONASS observations?
[ ] No
[X] Yes, please specify:
But this needs more time and more people.