From jimr at maia.usno.navy.mil Fri Sep 7 13:41:01 2001 From: jimr at maia.usno.navy.mil (Jim Ray (USNO 202-762-1444)) Date: Fri, 07 Sep 2001 16:41:01 EDT Subject: [IGSMAIL-3514]: SVN 19 anomaly test details (fwd) Message-ID: <200109072041.QAA20891@maia.usno.navy.mil> ****************************************************************************** IGS Electronic Mail 07 Sep 13:41:04 PDT 2001 Message Number 3514 ****************************************************************************** Author: Frank Lorge (forwarded by Jim Ray via NOAA/NGS) Subject: SVN 19 Anomaly Tests Date: Thu, 06 Sep 2001 10:43:25 -0400 From: "Frank Lorge" To: many addresses All, The final test plan for the SVN 19 waveform anomaly test was released yesterday. The test will be conducted next week, September 10-12. The goal of the test is to collect data on the failed hardware chain that caused the anomalous ('evil') waveform in 1993. During the test the satellite will be set unhealthy and should not create a problem for users. The failure was originally detected by differential GPS users using disparate receivers, and resulted in a relative position error of 3 to 8 meters. Errors of this magnitude would not normally be detected by most users. As noted above, since the satellite will be set unhealthy for this test, a normal receiver will not use the satellite in a solution. Specialized receivers will be used during the test to track the signal. Users who do experience problems during the test should report them through the Coast Guard 24-hour information watch. The phone number for the watch is (703) 313-5900 and email: nisws at navcen.uscg.mil. Pilots who experience problems should contact their nearest flight service station to report the details. Testing will be halted if a large number of users detect problems. The detailed schedule follows: Monday J253/1300 - J254/0306 Configuration 1 Tuesday J254/2003 - J255/0302 Configuration 1 Wednesday J255/2000 - J256/0258 Configuration 2 Notes: These dates are julian dates. Day 253 is September 10. All times are in GPS time, which is basically equivalent to UTC. Time 1300 therefore corresponds to 0900 on the east coast. In Configuration 1, the NDU Baseband and Processor will re-configured to the A-side, and the L1 MOD-IPA will also be configured on the A-side. In Configuration 2, the NDU Baseband and Processor will remain on the A-side, while the L1 MOD-IPA will be re-configured to the B-side. Note that transmission of P(Y) on L1 and L2 is at the discretion of the test operator (2 SOPS/DOUAN.) Any other comments or requests or requests for additional detail may be addressed through me. Frank Lorge GPS Civil Test Director frank.lorge at faa.gov 609-485-4588