| Date: | 2016-03-31 07:07:50 | |
| Sender: | Toshimichi Otsubo <t.otsubo@r.hit-u.ac.jp> | |
| Subject: | [SLR-Mail] No.2376: Small change in bias estimation procedure at Hitotsubashi University | |
| Author: | Toshimichi Otsubo, Hitotsubashi University | |
| Content: | Author: Toshimichi Otsubo, Hitotsubashi University Dear ILRS Colleagues, We have automatically been updating the SLR quality control reports every 6 hours at: http://geo.science.hit-u.ac.jp/slr/bias/ We have seen a large (> 100 microsec) time bias with a large error often for a relatively short high-sat pass, due to the correlation with a range bias, and it sometimes confused our users. Following comments from J Luck and V Glotov in 2015, time biases of GNSS and ETALON are now estimated only if a pass satisfies all of these: - it contains more than 4 good NPs (no change) - its length is longer than 120 min (was 60 min) - it covers both ascending and descending parts (new) Otherwise, only a range bias estimate will be given, and ”-------.- ( ----.- )” will be shown for the time bias column. As a result, a time bias is given only for a smaller number of ”nicely tracked” passes. I admit it is not an almighty solution, but the untrue large time bias cases are significantly reduced. This is implemented yesterday, 30 March 2016 (2016031606 and onwards). No change has been made for LAGEOS and low orbiters. We have also added the following satellites to our QC analysis. JASON-3 (tagged as JAS3), GALILEO-201, 202, 203, 204, 205, 206, 208 and 209 (F201 to F209), GLONASS-125, 128, 133 and 134 (GL25, GL28, GL33, GL34). Note that we do not include some of these satellites when the tracking data amount is low or the orbit fit is poor. Best Regards, Toshi ----- Toshimichi Otsubo Hitotsubashi University Web http://geo.science.hit-u.ac.jp/ Tel & Fax +81-42-580-8968 |