SiRF's
starIII chipset appears to dominate the GPS receiver market, at least where Windows devices are concerned. During the past few weeks alone, it has appeared here in -- from most to least recent -- the
Asus P526,
Maxian E900T,
Gigabyte Gsmart i350,
Michelin X-970T,
Santek SSGN3, and
E-Ten Glofiish X600. The starIII architecture can track 20 satellites at once and offers 200,000 correlators, features that make acquisition -- finding and locking onto enough satellites for operation -- relatively fast, according to the company.
Nonetheless, the company explains, a GPS receiver needs to know where each satellite is in the sky with a very high degree of accuracy. Every satellite requires 30 seconds to broadcast its precise location, data which is typically valid only for two to three hours. If anything interrupts the signal while receiving this data, such as a building or tree, the receiver has to wait another 30 seconds to completely download the data from the satellite.
Therefore, in real-world conditions it can take several minutes for a receiver to "warm start" -- obtain all the data it needs to perform its calculations and obtain a fix. But, it's said, the new SiRFInstantFixII technology can reduce warm starts to as little as five seconds.
According to SiRF, this is accomplished via "sophisticated, patent-pending algorithms" that enable a PND to model the behavior of visible GPS satellites during the day and predict their position in the sky for up to three days in the future. SiRFInstantFixII refines its calculations based on data it receives from the satellites being tracked while the PND is in use, and does so autonomously, without ever needing updates via Internet connectivity.
Kanwar Chadha, founder and vice president of marketing for SiRF, said "Our groundbreaking SiRFInstantFixII technology makes the frequent start-up waits for PNDs a thing of the past. By not requiring any network connectivity or downloads, it significantly improves the daily navigation experience for consumers of mobile navigation devices."
AvailabilitySiRFInstantFixII is available now to manufacturers of devices using starIII GPS receivers or SiRFatlas and SiRFtitan multifunction SoC navigation processors. In its statement, the company did not specify when PNDs employing the technology can be expected to go onto the market.
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