Global Positioning Systems

A space weapons test by China produced a significant amount of orbital space debris that may damage satellites in orbit, including those that provide positioning information.

The Chinese test, carried out on Jan. 11, was at once complex and very simple. The missile hit the satellite with deadly precision. The missile carried no bomb because it didn't need one. The satellite was pulverized by the impact. As of today, Kelso reports that American radar is tracking at least 525 pieces of debris from the collision -- each at least the size of a baseball. There are probably hundreds, if not thousands, of smaller ones. The pieces are gradually spreading out in a ring around the Earth, creating a vast area where spacecraft face increased danger of being hit. "We've already seen in the range of 500 to 600 events where some piece of debris from this one event was coming within 5 kilometers of some payload," said Kelso.

InfoWorld has a brief article about a new Swiss chip that appears to provide increased sensitivity, as well as utilising sats from both the Navstar and the formative Galileo.

The u-blox 5 chip, which Switzerland's U-blox plans to unveil at the 3GSM World Congress event in Barcelona next month, uses two global navigation satellite services: GPS, which was developed by the U.S. Department of Defense, and Europe's Galileo, the vendor said Wednesday. The technology has a tracking sensitivity of -160 dBm, which enables indoor coverage. The abbreviation dBm represents the power ratio in decibels (dB) with respect to 1 milliwatt (mW).

The serendipitous discovery of GPS signal degradation during a research experiment in 2005, has highlighted that degradation of up to 90% may occur around 2011-2012 when more solar flares are expected. This could impact all daytime users more than previously expected.