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Hi,
Does anyone has heard about A-GPS technology. What is it and which mobiles does have this. Like what the older mobiles have what if offers more than them. I want some information on this service. I am using a Nokia phone with GPS support which helps to guide the maps. Now I had found in a news that Nokia N95 gives a A-GPS support. What is it actually. Thanks in advance.
The A-GPS service that anticipates the future of GPS navigation. An A-GPS or Assisted GPS or AGPS or WAG (Wireless Assisted GPS), GPS uses the operator to help the mobile terminal to know which GPS signals must be followed. With this assistance, the signal search conducted by the terminal is greatly reduced.
In A-GPs the time required for the initial connection or TTFF (Time To First Fix) increases from several minutes to just seconds. Moreover, unlike traditional GPS receivers, the receiver A-GPS integrated in the terminal is able to detect and demodulate signals of very low magnitude. The standard GPS positioning is very effective in open environments with a clear view skyward. However, this performance deteriorates significantly in dense urban areas and inside buildings.
Parallel to GPS, other positioning technologies are used by mobile operators such as Cell-ID (identification of the cell), but they do not provide sufficient accuracy (300 m in urban area several kilometers in rural areas ) for a navigation service. Using the A-GPS technology provides operators with location data more accurate than Cell-ID and in places where GPS does not usually. For example, the server Alcatel 8608 provides an accuracy of about 3 to 5 meters outdoors.
Here is an example of an A-GPS server. The system is designed to operate independently from any mobile operator that the service is GSM, GPRS, Edge or UMTS. From the operator side, the A-GPS server includes three elements the first is an antenna that searches for the satellite information. Second is a platform (hardware and software) to perform positioning calculations and a computer (or gateway) that connects the server to the IP network.
In its classic version, the application connects to an external Bluetooth GPS receiver to determine the position of the phone. In the case of A-GPS, the application communicates with a server hosted by the operator. There are two steps are necessary to recover the position. In the first one at its inception, the mobile phone sends a request via the IP network to server A-GPS to know which GPS signals must follow and then he puts in conjunction with the satellite indicated by the server to its position. Therefore, the phone operates autonomously. If the phone loses the GPS signal, it then asks the assistance of A-GPS server to help.