Location registration system in mobile communication

Claim 1

(1) A location registration system in a mobile communication system comprising; a service area for mobile communication comprising a plurality of location registration areas each having a plurality of cells, and each cell being related to a related base station, a fixed home location register storing location identifier of each mobile station showing which location registration area each mobile station stays, a fixed mobile control center coupled with said home location register, a fixed telephone network, and a plurality of base stations each of which transmits radio wave to mobile stations staying in a related cell, a plurality of mobile stations coupled with one of the base stations through radio link, and having a location identifier corresponding to the same in said home location register, said location identifier in said home location register and in said mobile station being updated when the mobile station moves beyond border of location registration areas, to the location identifier of the location registration area in which the mobile station stays, a call from a fixed network to a mobile station being transmitted from the base stations which belong to the location registration area which the mobile station stays, to the mobile stations, CHARACTERIZED IN THAT each location registration area has a plurality of groups each having a plurality of cells so that the cells of any group overlap partly with the cells of other groups, but do not completely coincide with cells of other groups, each mobile station belongs to one of said groups, broadcast information from a base station to mobile stations for location updating includes a number of groups, and a plurality of location identifiers for each group, means for updating location identifier is provided so that when a location identifier in a mobile station does not coincide with anyone of the location identifers for the group to which the mobile station belongs in broadcast information, by updating location identifiers in said home location register and the mobile station, fixed network stores a paging table which lists a plurality of cells for each group for each location identifier, and paging information for call to a mobile station is transmitted by the base stations which are listed in the related group of the location registration area in said table.