Patent Application
20080081639
Wireless network 101 facilitates communication within a cellular network. Wireless network 101 also allows communication with a wireline network via a Public Switched Telephone Network (PSTN). Wireless network 101 can utilize a variety of wireless protocols.
Home MSC 103 typically is coupled to and controls a plurality of base stations, which in turn communicate with mobile units located within their location areas. Each base station is typically responsible for a specific geographical area, commonly referred to as a cell site. Home MSC 103 is preferably responsible for compiling call information for billing and handing off calls from one cell to another. In an exemplary embodiment, Home MSC 103 is a CDMA MSC.
Visited MSC 105 typically is coupled to and controls a plurality of base stations, which in turn communicate with mobile units located within their location areas. Only one cell site, cell site 115, is depicted in
Mobile unit 107 is a portable unit that is registered with Home MSC 103. Although mobile unit 107 is registered at Home MSC 103, mobile unit 107 can travel throughout communication system 100 and place and receive calls at other MSCs. As depicted in
A request is sent to wireless network 101 to locate mobile unit 107. Home MSC 103 determines (201) the last known location of mobile unit 107. This determination will produce the MSC at which mobile unit 107 last registered. In the exemplary embodiment depicted in
Home MSC 103 sends (203) a request to the last known MSC which mobile unit 107 registered with. In the exemplary embodiment depicted in
After receiving the request from Home MSC 103, Visited MSC 105 initiates (205) a location finding process for mobile unit 107. The visited MSC sends an SDPP message to mobile unit 107 to inform mobile unit 107 that it is to send its GPS information to home MSC 103. Mobile unit 107 determines its position with the information sent and the use of a pilot system, which preferably comprises three pilot signals. The information is sent to Home MSC 103.
Visited MSC 105 determines (206) if mobile unit 107 is located within the coverage area of visited MSC 105. If not, visited MSC 105 sends (208) a failure message to home MSC 103 indicating that mobile unit 107 is not located within the area covered by visited MSC 105. The process then ends (299).
If mobile unit 107 is located within the area covered by visited MSC 105 as determined at step 206, processing continues at step 207. Visited MSC 105 sends (207) location data relating to mobile unit 107 to Home MSC 103. Location data is preferably GPS coordinates, but can alternately be a cell site, a zip code, a street address, a city name, or any other suitable geographic location.
Home MSC 103 records (209) the information pertaining to mobile unit 107. In an exemplary embodiment, Home MSC 103 stores the information in a database, and includes the subscriber's record. In an alternate exemplary embodiment, home MSC 103 stores the information in a file in a working directory on home MSC 103. Further, home MSC 103 can send the information to the “ROP”, or it may send the information to a processor in wireless network 101 for further evaluation.
Home MSC 103 outputs (211) information pertaining to mobile unit 107 to an ROP. In an exemplary embodiment, home MSC 103 outputs the GPS coordinates onto the ROP using a write primitive.
Visited MSC 105 determines (212) if it has received a message from Home MSC 103 telling visited MSC 105 to stop determining the location of mobile unit 107. If visited MSC 105 has received such a message, the process ends (299). If visited MSC 105 has not received a stop message at step 212, processing returns to step 205, where visited MSC 105 continues the location finding mechanism.
While this invention has been described in terms of certain examples thereof, it is not intended that it be limited to the above description, but rather only to the extent set forth in the claims that follow.
