Decision device, decision method, mobile terminal, control method, location notification system, and location notification method

A decision device for controlling installation of a lighting device configured to transmit identification information by changing an output mode of emitted light in an indoor positioning system, the decision device comprising:

• at least one processor and a memory device storing instructions that, when executed by the at least one processor, cause the at least one processor to perform operations comprising:
• dividing a floor region of an indoor space into a plurality of spatial regions;
• defining adjacency relationships between the spatial regions based on shared boundaries between the spatial regions;
• for each of a plurality of candidate installation positions of the lighting device:
• specifying an irradiation target region on the floor region, wherein the irradiation target region is irradiated with the emitted light having the output mode changed to transmit the identification information when the lighting device is installed at the candidate installation position;
• and
• identifying, among the spatial regions, non-irradiation target regions not irradiated with the emitted light when the lighting device is installed at the candidate installation position;
• selecting a candidate installation position of the plurality of candidate installation positions, such that non-irradiation target regions corresponding to the selected candidate installation position are not adjacent to each other according to the defined adjacency relationships.