System and method for geographically locating a cellular phone
According to an embodiment of the invention, there is disclosed a method for geographically locating a cellular phone. The method comprises: determining an effective cell-area for each of a first cell and a second cell in a cellular network; and determining a handover area within which the cellular phone is likely to be located when control of the cellular phone is transferred from the first cell to the second cell; wherein the determination of the handover area and the effective cell-area for each of the first cell and the second cell are made based on a topological relationship between the first cell and the second cell. Further related apparatus embodiments are also disclosed.
1. A method of monitoring vehicle traffic flow by determining successive locations of a plurality of cellular phones located in a plurality of vehicles, the method comprising:
repeatedly determining the location of at least some of the plurality of cellular phones; and
sampling the locations of the at least some of the cellular phones to determine a present picture of vehicle traffic flow;
wherein determining the location of a cellular phone of the plurality comprises determining the area in which handover from a first cell to a second cell occurs, the determination of the area in which handover occurs being based on:
modeling at least a portion of a cell reception area of said first cell and said second cell; and
defining the area in which handover occurs to comprise overlapping portions of said first and second cell areas.
2. The method according to claim 1 , further comprising predicting future vehicle traffic conditions based on the present picture of traffic flow.
3. The method according to claim 1 , wherein the determination of the area in which handover occurs is made by consulting a database of pre-determined handover areas for cell pairs, using handover data from a cellular network.
4. A The method according to claim 3 , wherein the handover data comprises cell identifier data.
5. The method according to claim 3 , wherein the handover data comprises time advance data.
6. The method according to claim 1 , wherein the determination of the area in which handover occurs is made online using streaming handover data from a cellular network.
7. An apparatus for monitoring vehicle traffic flow by determining successive locations of a plurality of cellular phones located in a plurality of vehicles, the apparatus comprising:
a handover area module for defining a handover area comprising overlapping portions of a modeled cell reception area of at least a portion of each of a first cell and a second cell of a cellular network; and
a sampler module for sampling a set of repeated location determinations of at least some of the plurality of cellular phones, to determine a present picture of vehicle traffic flow, wherein each such location determination is based at least in part on the handover area defined by the handover area module for a given cellular phone moving between a given first cell and second cell of the cellular network.
8. The apparatus according to claim 7 , further comprising:
a predictor module for predicting future traffic conditions based on the present picture of traffic flow.
9. The apparatus according to claim 7 , further comprising:
a handover area database comprising pre-determined handover areas for cell pairs.
10. The apparatus according to claim 9 , wherein the handover area module is capable of consulting the handover area database using streaming handover data from the cellular network.
11. The apparatus according to claim 10 , wherein the handover data comprises cell identifier data.
12. The apparatus according to claim 10 , wherein the handover data comprises time advance data.
13. The apparatus according to claim 7 , wherein the handover area module is capable of determining the handover area online based on streaming handover data from the cellular network.