Method for estimating a radio coverage of a geographic area in a cellular mobile radio communication network

1. A method for estimating coverage of a selected geographic area by a cellular radio mobile communications network comprising a plurality of radio base stations, comprising:

dividing the selected area into a plurality of area elements;

determining expected serving radio base stations in said plurality of radio base stations expected to serve the area elements, based on an estimation of the strength of the radio electromagnetic field of the radio base stations in the area elements, said determining expected serving base radio stations comprising:

estimating for each radio base station of said plurality of radio base stations, a respective probabilistic distribution of the strength of the radio electromagnetic fields irradiated b the radio base station and perceived in each area element of said plurality of area elements; and

calculating for each radio base station of said plurality of radio base stations and for each area element of said plurality of area elements, respective probabilities that the radio base station serves said plurality of area elements, based on said estimated probabilistic distributions,

wherein:

estimation of the strength of the radio electromagnetic field is determined by simulating a radio electromagnetic wave propagation from the radio base stations in said geographic area and calculating an average electromagnetic field strength in each area element;

said estimating the probabilistic distributions comprises:

associating with the electromagnetic field strength a probabilistic distribution with average value and variance depending on said average electromagnetic field strength and at least one effect selected from the group of: an intrinsic wave propagation simulation error, a field fading error, an indoor field attenuation, and a body loss attenuation; and

determining respective probability density functions; and

said calculating the probabilities comprises:

determining exhaustive sets of events for which the radio base stations act as serving stations for the considered area element, based on a predetermined network access criterion implemented by the network for assigning a serving cell to a mobile terminal;

deriving from said sets of events respective integration domains for integrating the probability density functions; and

integrating the probability density functions over said integration domains.

2. The method of claim 1 , wherein the cellular radio mobile communications network comprises at least a first and a second radio access layers, wherein said determining exhaustive sets of events comprises taking into account a priority of radio base stations of the first radio access layers over radio base stations of the second radio access layer provided for in said predetermined network access criterion implemented by the network for assigning a serving cell to a mobile terminal.

3. The method of claim 1 , further comprising:

for the generic area element of said plurality of area elements, calculating a respective degree of coverage by the communications network as a sum of said probabilities that the radio base stations of said plurality serve said area element.

4. A method for estimating coverage of a selected geographic area by a cellular radio mobile communications network comprising a plurality of radio base stations, comprising:

dividing the selected area into a plurality of area elements;

determining expected serving radio base stations in said plurality of radio base stations expected to serve the area elements, based on an estimation of the strength of the radio electromagnetic field of the radio base stations in the area elements, said determining expected serving base radio stations comprising:

estimating for each radio base station of said plurality of radio base stations, a respective probabilistic distribution of the strength of the radio electromagnetic fields irradiated by the radio base station and perceived in each area element of said plurality of area elements; and

calculating for each radio base station of said plurality of radio base stations and for each area element of said plurality of area elements, respective probabilities that the radio base station serves said plurality of area elements, based on said estimated probabilistic distributions,

wherein:

estimation of the strength of the radio electromagnetic field is determined by simulating a radio electromagnetic wave propagation from the radio base stations in said geographic area and calculating an average electromagnetic field strength in each area element; and

said estimating the probabilistic distributions of the strength of the radio electromagnetic fields irradiated by the radio base stations and perceived in each area element, comprises: estimating, for each radio base station, an outdoor probabilistic distribution without taking into account the indoor field attenuation and an indoor probabilistic distribution taking into account the indoor field attenuation; and

said calculating, for each area element, the probabilities that the radio base stations serve the area element comprises:

calculating, for each radio base station, an outdoor probability and an indoor probability, respectively based on the respective outdoor probabilistic distribution and indoor probabilistic distribution:

associating with each area element a respective indoor degree factor, based on a density of buildings in said area element; and

combining, for each radio base station, the outdoor probability and the indoor probability using said indoor degree factor.

5. A non-transitory computer-readable medium tangibly storing a computer program comprising instructions, when executed, causing a hardware data processing system to carry out the steps of the method according to claim 1 .

6. A non-transitory computer-readable medium tangibly storing a computer program comprising instructions, when executed, causing a hardware data processing system to carry out the steps of the method according to claim 4 .