Mobile communication system wherein a base station transfers to another an identifier for a cell of call origination

Claim 2

A mobile communication system as claimed in Claim 1, wherein said identifier transmitting means transmits to said central office and to said mobile unit the first identifier transferred from the memory of said each base station to the memory of said different station if said second identifier is identical with the last-mentioned first identifier.

Claim 3

A mobile communication system as claimed in Claim 1 or 2, wherein the transmitter/receiver of said each base station further comprises signal transmitting means for transmitting to said mobile unit, when said communication is terminated at said each base station, a station channel disconnection signal carrying a termination identifier indicative of as one of said area identifiers the cell set comprising one of the last-mentioned cells in which said mobile unit is present upon termination of said communication.

Claim 4

A mobile communication system as claimed in any one of Claims 1 to 3, wherein the transmitter/receiver of said mobile unit further comprises signal transmitting means for transmitting to said each base station, when said communication is terminated at said mobile unit, a mobile channel disconnection signal which makes said each base station transmit to said central office and to said mobile unit a station channel disconnection signal carrying a termination identifier indicative of as one of said area identifiers the cell set comprising one of the last-mentioned cells in which said mobile unit is present upon termination of said communication.

Claim 5

Each of a plurality of base stations connected in a mobile communication system to a central office and collectively having an overall service area divided into cell sets which are identified by respective area identifiers and each of which is subdivided into at least one cell, the cells of said cell sets being in one-to-one correspondence to said base stations, said mobile communication system including a mobile unit movable in said overall service area and capable of carrying out communication with one of said base stations while present in one of the last-mentioned cells that corresponds to said one of the base stations, each of said central office, said base stations, and said mobile unit comprising a transmitter/receiver and a memory connected to said transmitter/receiver, wherein the transmitter/receiver of each base station comprises: transferring means for transferring a first identifier of said area identifiers from the memory of said each base station to the memory of a different station of said base stations when said mobile unit moves from a first cell of the last-mentioned cells to a second cell of the last-mentioned cells during said communication, said first cell being in the cell set identified by said first identifier and being in correspondence to said each base station, said second cell being in the cell set identified by a second identifier of said area identifiers and being in correspondence to said different station; and identifier transmitting means for transmitting said second identifier to at least one of said central office and said mobile unit if said second identifier is different from said first identifier upon termination of said communication, said identifier transmitting means transmitting said second identifier to make the transmitter/receiver of said at least one of the central office and the mobile unit update to said second identifier the memory connected to the last-mentioned transmitter/receiver.

Claim 6

Each of the base stations as claimed in Claim 5, wherein said identifier transmitting means comprises: storing means for storing in the memory of said each base station the first identifier which is transferred from the memory of another of said base stations; comparing means for comparing said second identifier with the first identifier stored in the memory of said each base station to judge whether or not said second identifier is different from the last-mentioned first identifier; first ready state setting means for setting a ready state for a next communication in said each base station after the last-mentioned first identifier is transmitted to said at least one of the central office and the mobile unit when it is judged that said second identifier is not different from the last-mentioned first identifier; component identifier transmitting means for transmitting said second identifier to said at least one of the central office and the mobile unit when said second identifier is different from the last-mentioned first identifier; and second ready state setting means for setting said ready state in said each base station after said second identifier is transmitted to said at least one of the central office and the mobile unit when said second identifier is different from the last-mentioned first identifier.

Claim 7

A central office for use in a mobile communication system comprising a plurality of base stations connected to said central office and collectively having an overall service area divided into cell sets which are identified by respective area identifiers and each of which is subdivided into at least one cell, the cells of said cell sets,being in one-to-one correspondence to said base stations, said mobile communication system including a mobile unit movable in said overall service area and capable of carrying out communication with one of said base stations while present in one of the last-mentioned cells that corresponds to said one of the base stations, each of said central office, said base stations, and said mobile unit comprising a transmitter/receiver and a memory connected to said transmitter/receiver; the transmitter/receiver of each base station comprising: (A) transferring means for transferring a first identifier of said area identifiers from the memory of said each base station to the memory of a different station of said base stations when said mobile unit moves from a first cell of the last-mentioned cells to a second cell of the last-mentioned cells during said communication, said first cell being in the cell set identified by said first identifier and being in correspondence to said each base station, said second cell being in the cell set identified by a second identifier of said area identifiers and being in correspandence to said different station; and (B) identifier transmitting means for transmitting said second identifier to at least one of said central office and said mobile unit if said second identifier is different from said first identifier upon termination of said communication; wherein the transmitter/receiver of said central office comprises updating means for updating to said second identifier the memory connected to the last-mentioned transmitter/receiver when supplied with said second identifier from said each base station.

Claim 8

A central office as claimed in Claim 7, said identifier transmitting means transmitting to said at least one of the central offica and the mobile unit the first identifier transfrred by said transferring means if said second identifier is not different from the last-mentioned first identifier upon termination of said communication, wherein said updating means stores in the memory connected to the last-mentioned transmitter/receiver the first identifier transmitted by said identifier transmitting means.

Claim 9

A mobile unit for use in a mobile communication system comprising a central office and a plurality of base stations connected to said central office and collectively having an overall service area divided into cell sets which are identified by respective area identifiers and each of which is subdivided into at least one cell, the cells of said cell sets being in one-to-one correspondence to said base stations, said mobile unit being movable in said overall service area and capable of carrying out communication with one of said base stations while present in one of the last-mentioned cells that corresponds to said one of the base stations, each of said central office, said base stations, and said mobile unit comprising a transmitter/receiver and a memory connected to said transmitter/receiver; the transmitter/receiver of each base station comprising: (A) transferring means for transferring a first identifier of said area identifiers from the memory of said each base station to the memory of a different station of said base stations when said mobile unit moves from a first cell of the last-mentioned cells to a second cell of the last-mentioned cells during said communication, said first cell being in the cell set identified by said first identifier and being in correspondence to said each base station, said second cell being in the cell set identified by a second identifier of said area identifiers and being in correspondence to said different station; and (B) identifier transmitting means for transmitting said second identifier to at least one of said central office and said mobile unit if said second identifier is different from said first identifier upon termination of said communication; wherein the transmitter/receiver of said mobile unit comprises updating means for updating to said second identifier the memory connected to the last-mentioned transmitter/receiver when supplied with said second identifier from said each base station.

Claim 10

A mobile unit as claimed in Claim 9, said identifier transmitting means transmitting to said at least one of the central office and the mobile unit the first identifier transferred by said transferring means if said second identifier is not different from the last-mentioned first identifier upon termination of said communication, wherein said updating means stores in the memory connected to the last-mentioned transmitter/receiver the first identifier transmitted by said identifier transmitting means.

Claim 11

A mobile unit for use in a mobile communication system comprising a central office and a plurality of base stations connected to said central office and collectively having an overall service area divided into cell sets which are identified by respective area identifiers and each of which is subdivided into at least one cell, the cells of said cell sets being in one-to-one correspondence to said base stations, said mobile unit buing movable in said overall service area and capable of carrying out communication with one of said base stations while present in one of the last-mentioned cells that corresponds to said one of the base stations, each of said central office, said base stations, and said mobile unit comprising a transmitter/receiver and a memory connected to said transmitter/receiver; the transmitter/receiver of each base station comprising: (A) transferring means for transferring a first identifier of said area identifiers from the memory of said each base station to the memory of a different station of said base stations when said mobile unit moves from a first cell of the last-mentioned cells to a second cell of the last-mentioned cells during said communication, said first cell being in the cell set identified by said first identifier and being in correspendence to said each base station, said second cell being in the cell set identified by a second identifier of said area identifiers and being in correspondence to said different station; and (B) signal transmitting means for transmitting to said mobile unit, when said communication is terminated at said each base station, a station channel disconnection signal carrying a termination identifier of said area identifiers, wherein the transmitter/receiver of said mobile unit comprises: identifier receiving means for receiving said first identifier from the memory of said each base station; comparing means for comparing said termination identifier with the first identifier received by said identifier receiving means to judge whether or not said termination identifier is different from the last-mentioned first identifier upon termination of said communication; and identifier transmitting means for making said signal transmitting means transmit to said central office the station channel disconnection signal carrying said second identifier as said termination identifier if it is judged that said termination identifier is different from the last-mentioned first identifier.

Claim 12

A mobile unit as claimed in Claim 11, wherein said identifier transmitting means makes said signal transmitting means transmit to said central office the station channel disconnection signal carrying the last-mentioned first identifier as said termination identifier if it is judged that said termination identifier is not different from the last-mentioned first identifier.

Claim 13

A mobile unit as claimed in Claim 11 or 12, wherein said comparing means comprises: storing means for storing the last-mentioned first identifier in the memory of said mobile unit; and component comparing means for comparing said termination identifier with the first identifier stored in the memory of said mobile unit to judge whether or not said termination identifier is different from the last-mentioned first identifier.

Claim 14

A mobile unit for use in a mobile communication system comprising a central office and a plurality of base stations connected to said central office and collectively having an overall service area divided into cell sets which are identified by respective area identifiers and each of which is subdivided into at least one cell, the cells of said cell sets being in one-to-one correspondence to said base stations, said mobile unit being movable in said overall service area and capable of carrying out communication with one of said base stations while present in one of the last-mentioned cells that corresponds to said one of the base stations, each of said central office, said base stations, and said mobile unit comprising a transmitter/receiver and a memory connected to said transmitter/receiver; the transmitter/receiver of each base station comprising: (A) transferring means for transferring a first identifier of said area identifiers from the memory of said each base station to the memory of a different station of said base stations when said mobile unit moves from a first cell of the last-mentioned cells to a second cell of the last-mentioned cells during said communication, said first cell being in the cell set identified by said first identifier and being in correspondence to said each base station, said second cell being in the cell set identified by a second identifier of said area identifiers and being in correspondence to said different station; and (B) signal transmitting means for transmitting to said each base station, when said communication is terminated at said mobile unit, a mobile channel disconnection signal carrying a termination identifier of said area identifiers; wherein the transmitter/receiver of said mobile unit comprises: identifier receiving means for receiving said first identifier from the memory of said each base station; comparing means for comparing said termination identifier with the first identifier received by said identifier receiving means to judge whether or not said termination identifier is different from the last-mentioned first identifier upon termination of said communication; and identifier transmitting means for making said signal transmitting means transmit to said central office the mobile channel disconnection signal carrying said second identifier as said termination identifier if it is judged that said termination identifier is different from the last-mentioned first identifier.

Claim 15

A mobile unit as claimed in Claim 14, wherein said identifier transmitting means makes said signal transmitting means transmit to said central office the mobile channel disconnection signal carrying the last-mentioned first identifier as said termination identifier if it is judged that said termination identifier is not different from the last-mentioned first identifier.

Claim 16

A mobile unit as claimed in Claim 14 or 15, wherein said comparing means comprises: storing means for storing the last-mentioned first identifier in the memory of said mobile unit; and component comparing means for comparing said termination identifier with the first identifier stored in the memory of said mobile unit to judge whether or not said termination identifier is different from the last-mentioned first identifier.