Apparatus and method for detecting a location of a mobile station in a mobile communication system

A mobile communication system comprising:

• a mobile station;
• plural base stations each configured to be directly connectable to the mobile station;
• a base station management device configured to change transmission power of the plural base stations in response to a communication state of a wireless network between the mobile station and the plural base stations;
• and
• a mobile station location information management device configured to manage location information of the mobile station, wherein
• the mobile station location information management device:
• creates a plurality of transmission power output data sets including individual pieces of transmission power data of the plural base stations with changing the transmission power of the plural base stations;
• creates a plurality of reception power data tables configured to individually correspond to the created plurality of transmission power output data sets wherein each of the plurality of reception power data tables includes plural pieces of divided area data, each of which includes reception power data of signals transmitted from the plural base stations, the plural pieces of divided area data individually corresponding to a plurality of individual divided areas within a location detection target area where communication is covered by the plural base stations;
• receives a changed transmission power data set including individual pieces of changed transmission power data of the plural base stations from the base station management device and selects a reception power data table corresponding to the received changed transmission power data set from among the created plurality of reception power data tables when the base station management device has changed the transmission power of the plural base stations after the mobile station has moved into the location detection target area;
• upon receiving a request for providing location information of the mobile station from an external device, instructs the mobile station to measure, in a location where the mobile station exists, pieces of reception power data of individual signals transmitted from the plural base stations with the changed transmission power;
• and
• receives a reception power data set including the individual pieces of reception power data measured by the mobile station, detects, as a specific location where the mobile station exists, a specific area indicated by divided area data where a difference with respect to the received reception power data set is slight, within the selected reception power data table, and transmits information indicating the detected specific location to the external device.

A mobile station location information management device comprising:

• a database creation unit configured to create a plurality of transmission power output data sets including individual pieces of transmission power data of plural base stations directly connectable to a mobile station with changing transmission power of the plural base stations and create a plurality of reception power data tables configured to individually correspond to the created plurality of transmission power output data sets wherein each of the plurality of reception power data tables includes plural pieces of divided area data, each of which includes reception power data of signals transmitted from the plural base stations, the plural pieces of divided area data individually corresponding to a plurality of individual divided areas within a location detection target area where communication is covered by the plural base stations;
• a data selection unit configured to receive a changed transmission power data set including individual pieces of changed transmission power data of the plural base stations from the base station management device and select a reception power data table corresponding to the received changed transmission power data set from among the created plurality of reception power data tables when a base station management device configured to change transmission power of the plural base stations in response to a communication state of a wireless network between the mobile station and the plural base stations has changed the transmission power of the plural base stations after the mobile station has moved into the location detection target area;
• and
• a mobile station location detection unit configured to, upon receiving a request for providing location information of the mobile station from an external device, instruct the mobile station to measure, in a location where the mobile station exists, pieces of reception power data of individual signals transmitted from the plural base stations with the changed transmission power, receive a reception power data set including the individual pieces of reception power data measured by the mobile station, detect, as a specific location where the mobile station exists, a specific area indicated by divided area data where a difference with respect to the received reception power data set is slight, within the selected reception power data table, and transmit information indicating the detected specific location to the external device.