[IGSREPORT-634] JPL Analysis Report (721)
Fri Dec 3 00:00:00 PST 1993
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IGS Electronic Report 3-DEC-1993 09:48:21 Message Number 634
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Author : David C. Jefferson
Subject: JPL Analysis Report (721)
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JPL ANALYSIS REPORT GPS-WEEK 0721 (DAYS 304-310, DATES 31-10-93 TO 06-11-93)
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Submitted by
D C Jefferson, J F Zumberge, G Blewitt, M B Heflin, F H Webb
all at the Jet Propulsion Laboratory, California Institute of Technology,
Pasadena, CA 91109.
The following files have been sent to the CDDIS:
______________________________________________________________________________
filename contents
______________________________________________________________________________
jpl07217.sum This text file.
jpl07217.erp Earth rotation parameters for GPS week 721.
jpl0721[0-6].sp3 GPS ephemerides for GPS week 721, sp3 format.
______________________________________________________________________________
GENERAL
Due to anti-spoofing, various receivers were tracking in cross-correlated mode
on days 304, 305, and 307-310 (October 31, November 1, 3-6). Except for day
305, which only had 4 hours of cross-correlated data for one satellite (PRN20),
our A-S strategy was used for analysis; see jpl07147.sum for details.
Additionally, we deweighted data from PRN20 on day 304, as normal weighting
produced many outliers. (We suspect that our editing of AS phase data misses a
number of bias breaks, and are working to improve our editing of AS data.)
According to the file gpsn4.txt obtained from tycho.usno.navy.mil, PRN31/GPS31
was scheduled unusable on day 304 from 18:00 UT for up to 12 hours for
repositioning. We have deweighted data from this satellite on this day and
the following days 305 and 306 as well.
According to IGS Mail Message #369, the antenna at MCMU (McMurdo Bay,
Antarctica) was relocated on day 304. Data was not available from this site on
this day, and we found it necessary to exclude data from this site on the
following day (305) as well. Also, tracking data from ALBH (Alberthead, Canada),
and HOBA (Hobart, Tasmania) have been deleted in accordance with the warnings
below. Inclusion of one or more of these sites has caused an excessive number
of outliers in our solutions.
Finally, please note that the analyses of days 308, 309, and 310 (November 4,
5, and 6) were done using a well-distributed subset of the ground stations
normally used. Day 308's analysis incorporated 28 sites, while the following
two days contained 12 sites each. The processing was done this way to reduce
the large number of outliers caused by the inclusion of various data. However,
the specific site(s) causing the problem is not presently known.
CHANGES TO IGS PRODUCTS
Beginning this week, we discontinue providing orbit files in the sp1 format. In
addition, we include two new pieces of information in the sp3 file: (i) the
sp3 header with an orbit quality indicator for each prn and (ii) precise clock
solutions. So that we can provide precise clock solutions every 15 minutes, we
have changed our data interval from 10 minutes to 7 1/2 minutes.
Our orbit quality indicator is calculated as follows: take the minimum value
over the day of sqrt(dx^2+dy^2+dz^2) for each prn, where dx, dy, and dz are the
prn's formal error in position. The value in the sp3 file is the log2 of this
value in mm. A value of 6, for example, indicates a formal error between 4.5 cm
(2^5.5 mm) and 9 cm (2^6.5 mm). Clock solutions whose formal error is less
than 1000 nsec are included in the sp3 file. Otherwise, the all 9's indicator
is used.
In analogy to our orbit repeatability table, we begin to provide a clock
repeatability table, with the rms (over time) difference between the day's
solution and the previous day's solution (for 0 <= t < 3 h) and the following
day's solution (for 21 <= t < 24 h). If there are exactly 6 hours used in the
comparison, the precision of the values in the table is to one decimal place,
otherwise, no decimal place is used. Our software produces clock estimates for
every epoch (i.e., every 7 1/2 minutes); however, only solutions with formal
errors less than 1000 nsec are included in the repeatability calculation. The
"units" of the rms values in the table are log(base-10) picoseconds. Whitespace
indicates no matching time-tags were found for a particular GPS component during
the overlap period on adjacent days.
We have also changed the way we handle deweighted satellites in our orbit
repeatability table. Satellites whose minimum 3drss formal error over the day
exceeds 1 meter are not included. Thus deweighted satellites show up as white-
space, as will satellites for which there is little data.
WARNING: Data from PRN20/GPS20 have been deweighted for day 304 (Oct 31) only.
WARNING: Due to the maneuver of PRN31/GPS31, data from this satellite have been deweighted for days 304 and 305 (Oct 31, Nov 1).
WARNING: Data from ALBH from been excluded for days 304 and 305.
WARNING: Data from HOBA have been excluded the entire GPS week 721.
WARNING: Data from MCMU have been excluced for day 305.
JPL LODR TABLE GPS week 721 (1993 Oct 31 - Nov 06)
MJD LODR +/-
(ms/day)
49291.5 2.59 0.01
49292.5 2.48 0.05
49293.5 2.65 0.05
49294.5 2.45 0.01
49295.5 2.55 0.02
49296.5 2.55 0.04
49297.5 2.49 0.03
END LODR TABLE
NOTE: In the following table, UT1R-UTC are the assumed nominal values from
IERS Bulletin-B predicts; estimated LODR values are given in the previous
table. See IGS Mail Message 97 for details.
JPL UTPM TABLE GPS week 721 (1993 Oct 31 - Nov 06)
MJD X Y UT1R-UTC XSIG YSIG UTSIG RMS XYC XUC YUC STA SAT PASS
'' '' sec '' '' sec
49291.5 -.07300 .42233 .35317 .00008 .00008 .00000 .0 .00 .00 .00 37 25 0
49292.5 -.07224 .42272 .35071 .00013 .00014 .00000 .0 .04 .00 .00 36 25 0
49293.5 -.07051 .42353 .34825 .00011 .00012 .00000 .0 .00 .00 .00 38 25 0
49294.5 -.06918 .42452 .34579 .00009 .00011 .00000 .0 .03 .00 .00 32 25 0
49295.5 -.06647 .42638 .34332 .00023 .00018 .00000 .0 -.07 .00 .00 28 25 0
49296.5 -.06362 .42734 .34084 .00022 .00025 .00000 .0 .11 .00 .00 11 25 0
49297.5 -.06271 .42917 .33837 .00018 .00017 .00000 .0 .18 .00 .00 12 25 0
END UTPM TABLE
The following table indicates the "3-dimensional orbit repeatability", as
defined in IGS Mail Message 37, for GPS week 721:
["3d rss" = sqrt(xrms**2 + yrms**2 + zrms**2)]
JPL ORBIT REPEATABILITY TABLE GPS week 721 (1993 Oct 31 - Nov 06)
93 10 31 93 11 1 93 11 2 93 11 3 93 11 4 93 11 5 93 11 6
prn 3d rss (m)
1 0.55 0.40 0.26 0.54 1.03 1.30 0.79
2 0.45 0.56 0.48 0.73 0.45 1.29 1.79
3 0.32 0.52 0.23 0.38 1.57 1.12 0.55
5 0.59 0.23 0.21 0.49 0.85 1.07 1.88
7 0.56 0.54 1.17 0.79 1.24 1.09 1.31
9 1.09 0.17 0.36 0.89 0.80 1.50 1.22
12 0.42 0.32 0.21 0.82 0.35 1.08 1.00
13 0.26 0.43 0.43 0.32 0.75 2.48 2.09
14 0.20 0.23 0.12 0.25 1.80 0.95 0.39
15 0.46 0.11 0.28 0.52 0.75 1.49 1.21
16 0.39 0.33 0.66 1.24 2.19 1.42 1.70
17 0.53 0.73 0.62 0.41 0.69 0.63 0.61
18 0.45 0.27 0.40 0.51 0.46 0.86 0.39
19 0.41 0.22 0.30 0.54 0.83 0.64 0.84
20 0.5 0.38 0.80 2.04 1.45 0.58
21 0.29 0.39 0.38 0.39 0.44 0.92 0.92
22 0.76 0.46 0.35 0.40 1.54 1.14 0.52
23 0.30 0.39 0.35 0.41 0.89 2.63 0.75
24 0.32 0.28 0.49 0.84 0.98 1.90 2.20
25 0.37 0.39 0.44 0.90 5.07 3.66 0.61
26 0.81 0.27 0.71 0.95 1.53 1.63 1.05
27 0.43 0.25 0.29 0.72 1.00 0.95 0.60
28 1.58 0.72 0.67 0.96 1.86 2.58 1.82
29 0.44 0.17 0.2 0.6
31 0.8 1.59 3.26 1.78
_______________________
#Indicates deweighted satellite.
END ORBIT REPEATABILITY TABLE
As described in IGS Mail Message 37, the following table compares the JPL
precise ephemerides with those from the broadcast ephemeris:
JPL COMPARISON OF BROADCAST NAVIGATION MESSAGE WITH PRECISE EPHEMERIDES
93 10 31 93 11 1 93 11 2 93 11 3 93 11 4 93 11 5 93 11 6
prn 3d rss (m)
1 11.3 12.1 11.1 10.6 9.3 8.0 7.0
2 3.4 2.7 5.4 7.4 6.7 4.8 4.4
3 9.5 9.4 10.1 10.6 10.2 10.3 11.5
5 16.4 16.2 14.5 14.6 14.4 21.1 17.3
7 7.7 8.0 9.4 15.6 22.2 17.8 12.7
9 27.7 3.8 4.2 4.1 4.7 8.9 12.1
12 3.2 3.3 3.6 3.5 0.0 3.3 2.8
13 8.89 5.8 3.5 4.92 5.4 11.3 10.5
14 6.0 8.1 8.9 7.3 6.0 5.5 6.3
15 3.8 4.2 2.7 4.3 2.7 3.0 0.0
16 7.5 10.3 11.4 10.4 9.4 9.8 8.9
17 3.1 2.5 2.1 2.5 2.6 2.7 2.6
18 13.2 10.2 7.0 7.7 6.6 7.7 11.5
19 8.5 7.1 7.0 7.0 6.3 7.9 7.7
20 5.1 6.0 5.0 4.3 4.8 5.3
21 4.0 3.1 3.4 4.1 4.6 2.8 13.3
22 9.0 7.4 8.5 10.6 7.6 4.7 4.9
23 3.4 3.5 2.6 4.3 2.4 1.9 2.6
24 8.5 6.7 7.1 8.3 9.1 8.1 9.8
25 7.9 9.4 8.7 7.0 7.5 6.5 7.3
26 5.5 4.6 4.9 5.7 5.1 4.4 6.7
27 6.3 6.6 5.7 6.2 6.9 6.6 7.0
28 5.5 9.9 14.7 12.1 11.5 8.2 13.5
29 7.7 8.6 9.6 18.7
31 6.7 6.4 7.3 12.9
_______________________
END COMPARISON OF BROADCAST NAVIGATION MESSAGE WITH PRECISE EPHEMERIDES
The following tables, as explained in IGS Report Nos. 99 and 295, indicate the
amount of global network tracking data used in this week's analysis:
JPL SITE SUMMARY TABLE (no. stations) GPS week 721 (1993 Oct 31 - Nov 06)
93 10 31 93 11 1 93 11 2 93 11 3 93 11 4 93 11 5 93 11 6
Fiducials 4.6 7.0 6.9 5.7 4.4 5.5 6.0
Total 20.1 34.4 37.1 24.5 18.6 8.8 9.8
END SITE SUMMARY TABLE
JPL GROUND STATION INCLUSION TABLE GPS week 721 (1993 Oct 31 - Nov 06)
93 10 31 93 11 1 93 11 2 93 11 3 93 11 4 93 11 5 93 11 6
site % data
ALBH 0 0 99 70 64 0 0
ALGO* 57 102 105 72 67 87 92
BRMU 58 81 104 65 63 0 0
DRAO 59 103 104 0 0 0 0
FAIR* 65 109 110 83 56 75 53
FORT 58 109 108 83 63 81 94
GODE 62 97 98 0 0 0 0
GOLD 49 92 94 47 69 0 0
GRAZ 0 95 96 0 0 0 0
HART* 67 102 89 84 84 88 90
JPLM 25 103 103 76 24 0 0
KIRU 66 85 93 82 68 0 0
KOKB* 58 105 106 74 0 75 91
KOSG 69 99 100 85 58 0 0
KOUR 50 100 103 77 74 0 0
MADR* 65 98 104 92 70 59 87
MASP 64 100 106 92 89 0 0
MCMU 8 0 111 0 0 0 0
MDO1 53 97 99 78 70 0 0
METS 71 100 106 90 76 0 18
NLIB 42 91 95 79 72 0 0
NYAL 65 111 112 86 0 0 0
ONSA 64 98 102 85 79 0 0
PAMA 0 0 88 73 0 0 0
PIE1 58 99 101 75 64 0 0
PINY 36 93 102 0 0 0 0
QUIN 48 95 94 71 59 0 0
RCM4 62 102 104 78 71 0 0
SANT* 63 79 83 79 78 82 93
STJO 44 99 102 84 80 0 0
TAIW 65 102 97 82 80 80 87
TIDB 69 94 86 79 57 82 93
TROM* 69 106 111 79 76 86 93
USUD 61 96 98 79 75 0 0
VNDP 65 102 102 0 0 0 0
WEST 59 91 0 0 0 0 0
YAR1* 71 101 83 83 79 83 94
YELL 60 107 109 84 0 0 0
_______________________
*Indicates fiducial site; #indicates deweighted site.
END GROUND STATION INCLUSION TABLE
JPL CLOCK REPEATABILITY TABLE GPS week 721 (1993 Oct 31 - Nov 06)
93 10 31 93 11 1 93 11 2 93 11 3 93 11 4 93 11 5 93 11 6
comp log10(rms/ps)
PRN01 4 3.5 3.7 3.9 4.5 4.7 4.4
PRN02 4 3.4 3.9 4.2 4.4 4.8 4.1
PRN03 4 3.6 3.7 4.4 4.4 4.6 4.1
PRN05 4 3.6 3.7 4.0 4.5 4.8 4.5
PRN07 4 3.6 3.8 4.0 4.4 4.8 4.1
PRN09 4 3.6 3.7 4.1 4.4 4.8 4.1
PRN12 4 3.6 3.7 4.1 4.3 4.8 4.1
PRN13 4 3.5 3.7 4.1 4 5 4
PRN14 4 3.4 3.7 3.7 4.4 4.8 4.0
PRN15 4 3.4 4 3.8 4.2 4.7 4.4
PRN16 4 3.6 3.8 4.4 4.6 4.5 4.2
PRN17 4 3.6 3.8 3.9 4.7 4.7 4.3
PRN18 4 3.4 3.9 4.1 4.4 4.8 3.8
PRN19 4 3.4 3.9 4.2 4.3 5 3.9
PRN20 3 3.8 4.0 4.5 4.8 4.5
PRN21 4 3.4 3.8 3.9 4.3 4.6 4.4
PRN22 4 3.5 3.8 4.4 3 5 4.4
PRN23 4 3.7 3.7 4.2 4.5 4.8 4.3
PRN24 4 3.6 3.7 3.6 4.6 4.7 4.0
PRN25 4 3.5 3.8 3.9 4.3 4.7 4.3
PRN26 4 3.7 3.7 3.8 4.4 4.6 4.3
PRN27 4 3.4 3.9 4.3 4.4 4.8 3.9
PRN28 4 3.5 3.8 4 4 4.8 4.3
PRN29 4 3.4 2 4
PRN31 4 4.6 4.8 4.5
ALBH 4 4.0 4
BRMU 4 3.5 3.7 4.2 4
CANB 4 3.6 3.9 4.1 4.4 4.7 3.7
FAIR 4 3.4 3.8 4.1 4.3 4.7 4
FORT 4 3.8 3.7 4.1 4 4.6 4.4
GGAO 4 3.5 2
GOLD 4 3.5 3.7 3.8 4
GRAZ 4 3.6 2
HART 3 3.7 3.7 5 4.3 4.9 4.3
HARV 4 3.4 3.7 3.9 4
JPLM 4 3.4 3.7 3.9 4
KIRU 3 3.4 3.8 4.1 4
KOKB 4 3.6 3.8 4 5 3.8
KOSG 4 3.7 3.7 4.2 2
KOUR 3 3.7 3.8 4.4 4
MADR 4 3.6 3.7 4.2 4.3 5 3.9
MASP 4 3.9 3.9 4.1 4
MDO1 4 3.3 3.8 4.2 4
METS 4 3.6 3.8 4.1 2 4
NALL 4 3.6 3.8 4
NLIB 4 3.4 3.8 4.1 4
ONSA 4 3.6 3.8 3.9 4
PAMA 4
PENT 4 3.5 2
PIE1 4 3.4 3.8 4.2 4
PINY 4 3.5 2
QUIN 4 3.4 3.8 4.2 4
RCM4 3 3.4 3.8 4.1 4
SANT 4 3.6 4 4.7 4.4 4.9 4.3
STJO 4 3.7 3.5 4.0 4
TAIS 4 3.6 3.8 4.1 4.4 4.8 4.1
TROM 3 3.6 3.8 3.8 4.1 4.7 4.0
USUD 4 3.2 3.9 4.2 3
VNDP 4 3.4 2
WEST 4 4
YAR1 4 3.1 3.9 3.8 4.3 4.7 4.1
YELL 4 3.4 3.7 4
_______________________
END CLOCK REPEATABILITY TABLE
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