Abstract: The present invention relates to a method of registering a mobile station in a cellular mobile radio system in which areas, each including a plurality of cells, form registration areas. Each registration area (RA1, RA2, RA3, . . . ) has its own identity (X). According to the proposed method, individual location areas are defined whenever registering a given mobile station with the intention of avoiding an unnecessarily high number of registrations in border areas of the different registration areas. A location area may have the form of a list of registration areas (X1, X2, X3, . . . ), which is stored in a mobile station (MS), or may be stored in the system (HLR, MSC) and transmitted to the mobile station (MS) via a base station (BS) in a given registration area, in conjunction with registration of the mobile station in this area.

Abstract: A method of setting up and handing off calls in a mobile cellular radio system in which consideration is given to the load capacity of several types of channels. The communication system determines the available capacity of the different groups of channels in the communication system whenever a new call needs to be set up. The system then assigns the new call to the group of channels with the most available channels if the requesting mobile station is a multi-mode mobile station, or the system hands off a multi-mode mobile station from a first group of channels to a second group of channels or vice versa to create free channels for calls from single mode mobiles.