Apparatuses and mobile stations for providing packet data communication in digital TDMA cellular systems

An apparatus for providing packet data communication to and from mobile stations in a digital TDMA cellular system having a plurality of base stations providing regular cellular control channels and regular cellular dedicated traffic channels;

• one or more mobile services switching centers, each being associated with a visitor location register and being coupled to a subordinated plurality of the base stations;
• and home location register means for storing information on mobile station subscribers, the apparatus comprising:
• channel providing means for providing, in at least some of the base stations, on a per cell basis, one or more shared packet data channels for packet transfer to and from the mobile stations, and packet transfer controlling means for controlling the packet transfer;
• channel defining means for defining, on a per cell basis, the packet data channel to be used for packet transfer;
• first packet data mode establishing means for establishing packet data mode for a mobile station to enable the mobile station to send and receive packets over the packet data channels;
• first packet transferring means for transferring packets between the mobile stations and base stations;
• second packet transferring means for transferring packets between the base stations and their respective superior mobile services switching centers;
• packet routing means for routing packets to and from a service area of a mobile services switching center;
• first means for performing cell selection for a mobile station in packet data mode;
• first means for performing location updating for the mobile station in packet data mode;
• first packet data mode maintaining means for maintaining the packet data mode for a roaming mobile station;
• and
• first packet data mode terminating means for terminating the established packet data mode for the mobile station.