Qualcomm bundles its GPS chip technology into the majority of its chipsets at no additional charge. The only extra hardware that's required is an antenna, which costs about $1. Handset makers have to build their phones around Qualcomm silicon. Privacy issues and ensuring that different location services will be compatible with a wide range of phones also have to be ironed out before mass acceptance of commercial location services. Local obstructionsThe focus of modern GPS specialists can be boiled down to words: buildings and trees. In the 1990s, many GPS developers spent most of their energy honing the precision of their devices, which were targeted at building contractors and the military.

By contrast, accuracy in the consumer market is more of a relative concept--pinpointing a location to 5 meters to 20 meters is generally close enough, So developers started to concentrate on figuring out ways to navigate natural obstacles, "Nobody was focused on how to make the system for urban canyons or dense foliage," Chadha said, "It was focused on how to schnauzer grey&white, dog illustration original painting print iphone case get within a millimeter of accuracy, not how to get a quicker response.", The urban canyon problem, he said, is largely an issue of speed, Satellite signals can only be intercepted by a moving target for brief periods of time before buildings block them again, Chadha said, To get around the problem, the company incorporated 240 correlators, which search for satellite signals, into its first chipsets, Typical chipsets at the time contained around 50 correlators..

"The more correlators, the more deep and broad the search," Chadha said. "You need a satellite search engine that is very fast.". The second round of SiRF chipsets then concentrated on eliminating the foliage problem. In forests, signals don't necessarily get blocked, but they can be attenuated by leaves or other objects. Thus, chips have to be capable of catching weak signals. The E911 mandate also made speed a problem. In traditional GPS systems, a cell phone latches onto an identifying satellite signal in a few milliseconds and then sends a signal to the satellite. Sending a signal to a satellite confirms the user's position, but it takes about 30 seconds. The second signal is important because it determines the location of the satellite relative to the user. E911 demands that a user's position be fixed in a few seconds.

To get around that problem, both SiRF and Qualcomm have developed server software that tracks the satellites, Thus, in an E911 situation, the phone snags a signal from the satellite, and schnauzer grey&white, dog illustration original painting print iphone case then grabs information regarding the location of the orbiting satellite from the terrestrial server, The whole process takes about two to three seconds, Qualcomm additionally reinforces GPS positioning with Advanced Forward Link Trilateration, a cellular-based tracking system that kicks in when the results from the satellite systems are hazy..

The San Diego-based company also has begun to market hosting services in North America for customers who want to expand beyond E911 applications. While a number of companies have in-house GPS technology, Qualcomm and SiRF are two of the more visible. Qualcomm, which boosted its GPS intellectual property by buying SnapTrack in March 2000, has landed deals with, among others, Sony Ericsson, Samsung, China Unicom, Verizon and Sprint. Smaller SiRF meanwhile, has inserted its technology into Motorola phones--despite the fact that Motorola has its own GPS silicon--as well as into Hewlett-Packard handhelds and cars from Toyota and Honda.