Traffic hot spot locating method

A method for locating hot spots of telephone traffic in a cell in a digital cellular mobile system comprising:

• broadcasting an adjacent cell list to mobile stations in the cell;
• measuring the received signal level of the adjacent cells in the mobile stations with an ongoing call;
• reporting the measuring results from the mobile stations to the cellular network;
• determining for each mobile station a timing advance value which is proportional to the distance between the mobile station and the serving base station;
• determining a hot spot of telephone traffic in the cell using the adjacent cell measurement and the timing advance values by
• dividing a timing advance range into sub-ranges,
• searching for the timing advance sub-range having the highest number of measurement results within a specific measurement sequence,
• selecting N adjacent cells included most frequently in the adjacent cell measurement reports in the searched timing advance sub-range where N=2,3, . . . ,
• forming a matrix of the measured signal levels of the N adjacent cells in the timing advance sub-range, and
• determining the hot spot of the cell on the basis of the coverage area information of N adjacent cells, the signal level matrix and the timing advance sub-range.

A system for locating hot spots of telephone traffic in a cell in a digital cellular mobile network, comprising:

• a base station arranged to broadcast an adjacent cell list to mobile stations in the cell,
• mobile stations with an ongoing call which are arranged to measure the received signal level of the adjacent cells and report the measurement results from the mobile stations to the cellular network,
• a base station arranged to determine a timing advance value proportional to the distance between the mobile station and the serving base station,
• a unit to determine a hot spot in the cell using the adjacent cell measurement and the timing advance values, the unit including
• a dividing unit to divide a timing advance range into sub-ranges,
• searching circuitry to search for the timing advance sub-range having the highest number of measurement results within a specific measurement sequence,
• circuitry to select N adjacent cells included most frequently in the adjacent cell measurement reports in the searched timing advance subrange where N=2,3, . . . ,
• matrix forming circuitry to form a matrix of the measured signal levels of these N adjacent cells in the timing advance sub-range, and
• circuitry to determine the hot spot of the cell based on the coverage area information of N adjacent cells, the signal level matrix and the timing advance sub-range.

A system for locating hot spots of telephone traffic in a cell in a digital cellular mobile network, comprising

• a base station arranged to broadcast an adjacent cell list to mobile stations in the cell,
• mobile stations with an ongoing call, the mobile stations being arranged to measure the received signal level of the adjacent cells and report the measurement results from the mobile stations to the cellular network,
• a base station arranged to determine a timing advance which is proportional to the distance between the mobile station and the serving base station,
• a unit to determine a hot spot in the cell using the adjacent cell measurement and the timing advance values, and further including
• circuitry to divide a timing advance range into sub-ranges,
• circuitry to form groups of N cells from the adjacent cells, each group having a timing advance distribution counter for each of said timing advance sub-range, where N=2,3, . . . ,
• selecting circuitry to select from each measurement report of the mobile station N adjacent cells whose measured received signal levels are the strongest,
• an incrementing unit to increment a timing advance distribution counter in the adjacent cell group which contains the selected adjacent cells, and
• circuitry to determine the distribution of mobile stations in a cell based on coverage area information of the adjacent cells and the values of the distribution counters cumulated during a specific measurement sequence.