Vancouver, Canada – April 1, 2009; Rx Networks, Inc., today announced that ST-Ericsson, a leader in mobile platforms and semiconductors has licensed Rx Networks GPStream™ technology for use with their GPS solutions. GPStream™ technology allows GPS based mobile devices to calculate and retain predicted satellite position information. This makes satellite acquisitions very fast for a better user experience, and enables devices to operate in weaker signal environments. Overall improvements include: significantly reduced Time To First Fix (TTFF), lower power consumption and improved usability inside buildings.

“The ST-Ericsson GPS solution comes in an impressively small form factor with low power consumption,” said Guylain Roy-MacHabée, President and CEO of Rx Networks. “This provides a lot of flexibility when designing into space constrained platforms like mobile devices.”

“Having the GPStream™ technology integrated into our GPS solutions makes commercial deployment simple for our customers,” said Nick Taluja, Head of Product marketing of ST-Ericsson, “this allows us to provide our customers with an industry leading portfolio of turnkey assisted GPS solutions.”

GPStream™ PGPS™ extended ephemeris feature enables the fastest possible TTFF by eliminating network overhead associated with real time network overhead associated with SUPL solutions. The solution requires miniscule 2Kbyte weekly downloads which make it ideal for mobile handsets.

GPStream™ SAGPS™ does not require any network connectivity at all. Originally targeting personal navigation devices, the solution has also found use in emerging markets where consumers like advanced handset products but are sensitive to recurring network service fees and roaming charges.

About Rx Networks

Rx Networks is a private, venture funded mobile positioning technology and global services company. Its GPS acceleration and assistance solutions uniquely reduce GPS wake-up times to mere seconds while improving GPS signal lock in challenging indoor and urban environments. Rx Networks licenses its GPStream solutions to location service providers, GPS semiconductor vendors and mobile device manufacturers to help them deliver a Click’n Go!™ GPS user experience for virtually any GPS enabled device.

Since the advent of GPS systems, the cost of production has decreased to the consumer so much that it’s now quite practical to incorporate the technology into systems one would never have though of a few years ago. Examples are GPS Running Watches, and dog tracking collars, gps wrist watch to name a few.

In order to determine if some of these commercially available units are for you, it’s likely wise to understand a little of the history & workings of present GPS systems.

Global Positioning System satellites transmit signals to equipment on the ground. GPS receivers passively receive satellite signals; they do not transmit. GPS receivers require an unobstructed view of the sky, so they are used only outdoors and they often do not perform well within forested areas or near tall buildings. GPS operations work on a on a very accurate time reference, which is provided by atomic clocks at the U.S. Naval Observatory. Each GPS satellite has atomic clocks on board.

Each GPS satellite transmits data that indicates its location and the current time. All GPS satellites synchronize operations so that these repeating signals are transmitted at the same instant. The signals, moving at the speed of light, arrive at a GPS receiver at slightly different times because some satellites are somewhat farther away than others. The distance to the GPS satellites can be determined by estimating the amount of time it takes for their signals to reach the receiver. When the receiver estimates the distance to at least four GPS satellites, it can calculate its position in three dimensions.

There are at least 24 operational GPS satellites at all times. The satellites, operated by the U.S. Air Force, orbit with a period of 12 hours. Ground stations are used to precisely track each satellite’s orbit.

Determining Position

A GPS receiver “knows” the location of the satellites, because that information is included in satellite transmissions. By estimating how far away a satellite is, the receiver also “knows” it is located on the surface of an imaginary sphere centered at the satellite. It then determines the sizes of several spheres, one for each satellite. The receiver is located where these spheres intersect.

GPS Accuracy
The accuracy of a position determined with GPS depends on the type of receiver. Most hand-held GPS units have about 10-20 meter accuracy. Other types of receivers use a method called Differential GPS (DGPS) to obtain much higher accuracy. DGPS requires an additional receiver fixed at a known point nearby. Observations made by the stationary receiver are used to correct positions recorded by the roving units, producing an accuracy greater than 1 meter.

When the system was created, timing errors were inserted into GPS transmissions to limit the accuracy of non-military GPS receivers to about 100 meters. This part of GPS operations, called Selective Availability, was eliminated in May 2000.