| 摘要 |
A cellular telephone having a global positioning system (GPS) receiver using a blended combination of GPS signals from GPS satellites and GPS pseudolites for determining a location. The cellular telephone includes a cellphone transceiver and a GPS receiver. The cellular transceiver receives wireless downlink cellphone signals from the cell site transceiver and transmits wireless uplink cellphone signals to the cell site transceiver. The cell site transceiver passes voice and data from the downlink and uplink cellphone signals within a local area into the worldwide network of telephone services. The GPS receiver receives satellite GPS signals from GPS satellites and pseudolite GPS signals from GPS pseudolites. The GPS pseudolites augment the GPS satellites for the local area by broadcasting pseudolite GPS signals having location-determination information with a format that is similar to the format in the satellite GPS signals. The GPS receiver uses either the satellite GPS signals, the pseudolite GPS signals, or a blended combination of the satellite and pseudolite GPS signals for determining its location. Then, the cellphone transceiver reports the location to the cell site transceiver in the uplink cellphone signal. The cell site transceiver transmits a downlink cellphone signal having acquisition aiding information optionally including GPS-based time; ephemeris orbital parameters for GPS satellites; and pseudorandom (PRN) codes, locations, and signal characteristics used by GPS pseudolites in the local vicinity. The GPS receiver in the cellular telephone uses the acquisition aiding information for speeding the time to the first location fix.
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