Next GPS IIF in October
The next GPS satellite, Block IIF-3 (SVN65), scheduled to be launched on October 4, will be positioned in orbital slot 1, which is in plane A. This slot is currently occupied by a Block IIA satellite, SVN39, operating as PRN09. SVN39 is one of the oldest operating satellites in the GPS fleet, dating from June 1993. SVN65 will the the third of a projected 12 IIF satellites to attain orbit.
Galileo IOV Tandem in October, Too
The previously announced September 28 launch date for the second set of Galileo IOV satellites has reportedly been pushed back to October 10.
Meanwhile, after more than four years of service as a Galileo testbed satellite, GIOVE-B was retired on July 23. Its navigation transmitters were switched off, according to an announcement from the European Space Agency, and the satellite’s height was raised in a series of steps to a graveyard orbit where there will be no danger of it interfering with the operational Galileo satellites or other spacecraft.
The SES-5 geostationary communications satellite (also known as Sirius 5 and Astra 4B), launched in July, arrived at its orbital slot of 5 degrees east longitude late that month. The current position is actually about 5.2 degrees. The satellite carries L1 and L5 transponders for the European Geostationary Navigation Overlay Service (EGNOS) satellite-based augmentation system. The GPS Directorate has assigned C/A PRN code 136 and L5 PRN code 136 for use by the satellite.
GAGAN in September
India’s GSAT-10 telecommunications satellite — one of two passengers for Arianespace’s upcoming Ariane 5 mission on September 21 — has completed pre-flight preparations at the Spaceport in French Guiana. Aboard GSAT-10 is the GAGAN (GPS and GEO augmented navigation) payload, which will support the Indian government’s implementation of a satellite-based regional capability to assist aircraft navigation over Indian airspace and in adjoining areas. GSAT-10 is expected to be positioned at 83 degrees east longitude and use PRN code 128. It will join the first GAGAN-equipped satellite, GSAT-8, launched in May 2011, and now at 55 degrees east longitude and transmitting test signals on the L1 frequency using C/A PRN code 127. Although GSAT-8 reportedly carries a dual-frequency transponder, no L5 signals from this satellite have yet been detected by International GNSS Service tracking stations.
GLONASS SBAS in September as Well
Luch-5B, the second of three geostationary satellites to reactivate Roscosmos’s Luch Multifunctional Space Relay System, is scheduled for launch no earlier than November 1, 2012, to be positioned at 16 degrees west longitude. The system’s multi-functional satellites carry transponders for the System for Differential Correction and Monitoring (SDCM), Russia’s satellite-based augmentation system. The transponders will broadcast GNSS corrections on the standard GPS L1 frequency using C/A PRN codes assigned by DoD’s GPS Directorate.
Luch-5A, launched in December 2011, has been placed in an orbital slot at 95 degrees east longitude. It began transmitting corrections on July 12, using PRN code 140.
SVN49 Back on the Air, Unhealthy
The GPS Block IIR-M satellite, SVN49, briefly resumed transmissions as PRN24 on August 9. The signals were marked unhealthy and the satellite was not included in broadcast almanacs. SVN49 was launched in March 2009, but remains out of service until an L1/L2 satellite multipath issue is resolved. Although not in the almanacs, a number of stations of the International GNSS Service tracked SVN49. See http://gge.unb.ca/test/IGS_stns_tracking_G24_223.pdf. SVN49 stopped transmitting signals as PRN24 on August 22. SVN49 previously operated between March 28, 2009, and May 6, 2011, as PRN01, and between February 2 and March 14, 2012, as PRN24.
Beidou Begins Testing Network
China will build a Beidou testing and certification network over the next three years to sharpen the system’s global competitiveness, according to a statement from China’s Certification and Accreditation Administration. By 2015, a national testing center will be set up in Beijing, while seven local sub-centers will be established across the nation, it said. The centers will test the safety and accuracy of products designed for use with Beidou and qualify them for civilian use. China plans to launch 30 satellites to complete the system by 2020.
The launch of next two Beidou-2/Compass medium-Earth-orbit satellites, M2 and M5, did not occur in August as was previously speculated. A knowledgable source states: “All three active Chinese tracking ships have retreated to their home base Jiangyin, north of Shanghai. (Two ships are required for tracking down-range for a typical Chinese beyond-low-Earth-orbit launch.) The launch was put off for the remaining part of August and at least the first couple of weeks in September. The most recently speculated launch date is September 18.”