Subject: [IGSMAIL-5509]: PRN32 tracking data statistics
From: Stefan Schaer <[email-masked]>
To: igsmail <[email-masked]>
Date: Wed, 20 Dec 2006 18:18:23 +0100

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IGS Electronic Mail      20 Dec 09:18:32 PST 2006      Message Number 5509
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Author: Stefan Schaer

Dear IGS colleagues,

First PRN32/SVN23 tracking data was collected by the IGS /IGLOS receiver
network from day 336 through day 340, 2006. Please be referred to NANU
message 2006155 (also attached to this mail)

   http://www.navcen.uscg.gov/ADO/GpsActiveNanu.asp

and IGS Mail 5499

   http://igscb.jpl.nasa.gov/mail/igsmail/2006/msg00222.html

On the basis of

   http://www.aiub.unibe.ch/download/igsdata/y2006/odata_gps_d336.txt
   http://www.aiub.unibe.ch/download/igsdata/y2006/odata_gps_d337.txt
   http://www.aiub.unibe.ch/download/igsdata/y2006/odata_gps_d338.txt
   http://www.aiub.unibe.ch/download/igsdata/y2006/odata_gps_d339.txt
   http://www.aiub.unibe.ch/download/igsdata/y2006/odata_gps_d340.txt

we compiled a list of all involved receivers and checked how many GNSS
stations equipped with a specific receiver model did sample G12, G15,
and in particular G32 (these three GPS satellites were permanently
marked unhealthy during this period):

AOA BENCHMARK ACT    ( 19):  G12 (18)  G15 (18)
AOA SNR-12 ACT       (  5):  G12 ( 5)  G15 ( 4)
AOA SNR-8000 ACT     ( 11):  G12 (11)  G15 ( 8)
ASHTECH UZ-12        ( 48):  G12 (34)  G15 (33)  G32 (34)
ASHTECH Z-XII3       ( 49):  G12 ( 2)  G15 ( 2)  G32 ( 2)
ASHTECH Z-XII3T      ( 14):
ASHTECH Z18          ( 11):  G12 ( 6)  G15 ( 1)
BLACKJACK            (  2):  G12 ( 2)  G15 ( 1)
JPS EUROCARD         (  1):
JPS E_GGD            (  9):
JPS LEGACY           ( 18):  G12 (13)  G15 (13)  G32 (13)
LEICA CRS1000        (  1):  G12 ( 1)  G15 ( 1)
LEICA GRX1200        (  6):
LEICA GRX1200PRO     (  3):            G15 ( 1)
LEICA RS500          (  1):
LEICA SR520          (  1):
NOV EURO4-1.00-222   (  1):
ROGUE SNR-12 RM      (  1):  G12 ( 1)
ROGUE SNR-8000       ( 11):  G12 (10)  G15 ( 8)
SEPT POLARX2         (  4):  G12 ( 3)  G15 ( 3)  G32 ( 3)
TPS EUROCARD         (  1):
TPS E_GGD            (  8):  G12 ( 6)  G15 ( 6)  G32 ( 6)
TPS GB-1000          (  3):
TPS LEGACY           (  3):  G12 ( 3)  G15 ( 3)  G32 ( 3)
TPS ODYSSEY_E        (  3):  G12 ( 2)  G15 ( 2)  G32 ( 2)
TRIMBLE 4000SSE      (  1):
TRIMBLE 4000SSI      ( 19):
TRIMBLE 4700         (  4):
TRIMBLE 5700         (  3):
TRIMBLE NETR5        (  2):  G12 ( 2)  G15 ( 2)
TRIMBLE NETRS        ( 11):  G12 ( 4)  G15 ( 4)

Note that the numbers in brackets correspond to the number of stations
equipped with the listed receiver model, or the number of stations that
observed the indicated GPS satellite (G12, G15, or G32, all considered
for IGS analysis).

A station observing at least one satellite marked unhealthy (G12 or G15)
should be able to track G32, too.  This is, however, not the case for
the following GNSS receiver models (cf. list above):
- AOA
- ASHTECH Z18
- BLACKJACK
- LEICA
- ROGUE
- TRIMBLE

It is worth mentioning that IGS/IGLOS receiver models tracking PRN32 do
not show any problem in tracking the two other satellites marked
unhealthy (identical numbers in brackets for G12 and G15).

Best regards,

The CODE AC Team

NANU message 2006155:

NOTIC ADVISORY TO NAVSTAR USERS (NANU) 2006155 NANU TYPE: GENERAL

*** GENERAL MESSAGE TO ALL GPS USERS ***

An initial assessment period for SVN 23 utilizing PRN 32 was
accomplished 1 December to 6 December 2006; SVN 23 is no longer
transmitting L-band. During this assessment period SVN 23 was
broadcasting L-band and set unhealthy. SVN 23 was not included in the
operational constellation almanac. Any users that experienced unusual
performance from GPS user equipment during this period should contact
the GPS Operations Center.

Approximately 10 January 2007, SVN 23 utilizing PRN 32 will be turned
on; transmitting L-band and kept unhealthy. SVN 23 will still not be
included in the operational constellation almanac. The GPS Operations
Center will transmit a GENERAL NANU reminding users of this activity.

POC:  GPS Operations Center
Phone:  DSN 560-2541; Comm. 719-567-2541
E-mail:  [email-masked]
Website:  http://gps.afspc.af.mil/gpsoc/

*** GENERAL MESSAGE TO ALL GPS USERS ***