GPS Signal Reception
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The TeleType Bluetooth GPS Receiver offers high position accuracy and fast Time-To-First-Fix (TTFF). These rely on environmental factors, such as where the receiver is located and the initial state of the receiver. While attempting a position fix, the receiver needs to be locked-on to at least four satellites. The TeleType Bluetooth GPS Receiver then uses the signals received from the satellites, along with data from the receiver's digital memory about the last position fix, in order to compute the current location of the device.

Environmental factors that influence position accuracy and initial GPS position fix are:
·Tall buildings  
·Narrow street and passageway  
·Protection film on glass  
·Heavy foliage  
·Large cliffs  
·Other obstructions where the satellite signals may blocked  
·Poor satellite geometry situations  

The initial state of the receiver refers to the last status of the receiver in memory. This mainly determines the length of time it will take for your GPS receiver to obtain a position fix. Your position can be quickly fixed within 10 seconds from a "hot-start" state, and typically 45 seconds from a "cold-start" state. It takes at least 3 to 5 minutes to obtain a position fix from a completely restart-state, for example, flying at a distance over 300 miles from the initial origin.

The TeleType Bluetooth GPS Receiver uses the satellite signals to calculate your exact location by computing your distance from the satellites. The position data within the receiver is then converted into latitude and longitude coordinates, which are usually provided in the geodetic datum on which the GPS is based (WGS84). Using the wrong datum can result in position offsets for many miles.

In addition to incorrect datum, there are number of positioning errors that can occur which affect the accuracy of your TeleType Bluetooth GPS Receiver. The major errors including satellite orbiting errors, poor satellite geometry, multi-path signals, atmospheric delay, and receiver clock timing.