Method and system for providing assistance data for A-GPS location of handsets in wireless networks

A method for estimating the location of a device, comprising the steps of:

• (a) determining a boundary for a region in which the device is located;
• (b) determining two or more available satellites that are observable along said boundary;
• (c) receiving, at the device, assistance data from a communications network, said assistance data including information from said two or more available satellites;
• (d) receiving, at the device, a plurality of signals comprising one signal from each of the two or more available satellites;
• and
• (e) estimating, at the device, a location of the device as a function of said plurality of signals.

A system for determining the location of a device from signals received from a plurality of Global Navigation Satellite System (“GNSS”) satellites comprising:

• (a) circuitry for determining a boundary for an approximate area in which a wireless device is located;
• (b) circuitry for determining a first plurality of satellites that are observable along said boundary;
• (c) a transmitter for transmitting assistance data to said wireless device, said assistance data including information from said first plurality of satellites;
• and
• (d) circuitry for determining, at the wireless device, the location of the wireless device from said information included in said assistance data.