Mobile communication system, mobile terminal, base station, mobile switching station and mobile communication control method

• US 6,285,684 B1
• Filed: 05/05/1997
• Issued: 09/04/2001
• Est. Priority Date: 10/30/1996
• Status: Expired due to Fees

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Suzuki, Norio, Tomita, Kazuhiko, Morita, Eiji, Kameyama, Keiji, Samejima, Noriko
• Primary Examiner(s): Ton, Dang
• Assistant Examiner(s): Sam, Phirin
• Application Number:
  US08/851,421
• Time in Patent Office: 1,583 Days
• Field of Search: 370/394, 370/395, 370/397, 370/474, 370/466, 370/471, 370/338, 370/401, 370/331, 370/332, 370/473
• US Class Current: 370/471
• CPC Class Codes: H04L 2012/5607 Radio
• CPC Class Codes: H04L 2012/563 Signalling, e.g. protocols, reference model
• CPC Class Codes: H04L 2012/5652 Cell construction, e.g. including header, packetisation, depacketisation, assembly, reassembly
• CPC Class Codes: H04Q 11/0478 Provisions for broadband connections
• CPC Class Codes: H04W 36/00 Hand-off or reselection arrangements

Abstract

A mobile communication system includes a mobile terminal, a base station, and a mobile switching station. The mobile terminal, the base station and the mobile switching station are constructed so that communication information and control information are transferred by an asynchronous transfer mode (ATM) cell between the mobile terminal and the base station, between mobile switching station and the base station.

Claims

1. A mobile communication system comprising:

a first mobile terminal;

a first base station;

a first mobile switching station; and

a second mobile switching station;

said first mobile terminal, said base station and said first mobile switching station being constructed so that communication information and control information are transferred by an asynchronous transfer mode (ATM) cell between said first mobile terminal and said first base station, between said first mobile switching station and said first base station;

said first and second mobile switching stations being constructed so that the communication information and the control information are transferred by the ATM cell between said first and second mobile switching stations,

wherein said second mobile switching station is specified by a mobile switching station number in a cell header part of the ATM cell in said first mobile switching station, the ATM cell is transferred between said first and second mobile switching stations which are mutually specified, and said first mobile terminal communicates with a second mobile terminal via said first base station and a second base station which are coupled to said first and second mobile switching stations, mutually different.

2. A mobile terminal for use in a mobile communication system including mobile terminals, base stations and mobile switching stations, said mobile terminal comprising:

a radio transmitter/receiver part transmitting and receiving an asynchronous transfer mode (ATM) cell;

an audio input/output part inputting and outputting audio information;

a transmitting cell assembling part assembling the ATM cell from the audio information output from said audio input/output part and control information, and transferring the ATM cell to said radio transmitter/receiver part;

a received cell disassembling part disassembling the ATM cell received by said radio transmitter/receiver part to restore audio information, and transferring the restored audio information to said audio input/output part; and

a control processor controlling assembling and disassembling of the ATM cell in said transmitting cell assembling part and said received cell disassembling part, and controlling a transmission timing of the ATM cell from said radio transmitter/receiver,

wherein said transmitting cell assembling part includes a cell accumulating part accumulating ATM cells which await transmission,

said control processor controls said transmitting cell assembling part to notify the base station of a number of accumulated ATM cells which await transmission in the cell accumulating part, and

said control processor controls said radio transmitter/receiver part to transmit the ATM cell with a transmission timing which is notified from the base station in correspondence with said number of accumulated ATM cells.

3. The mobile terminal as claimed in claim 2, wherein said transmitting cell assembling part adds a cell number which indicates a transmitting order to a cell header part of the ATM cell.

4. The mobile terminal as claimed in claim 2, wherein said control processor determines the transmission timing to a timing which is a predetermined time after a reception timing of the ATM cell by said radio transmitter/receiver part from the base station.

5. A mobile communication control method which controls communication in a mobile communication system including mobile terminals, base stations and mobile switching stations, said mobile communication control method comprising:

transferring call control information and audio information by the ATM cells between the base stations and the mobile switching stations respectively;

switching the ATM cells in the mobile switching stations depending on tag information in a respective cell header part of the ATM cells, said tag information indicating a structure of a corresponding one of the mobile switching stations the steps of;

receiving the respective ATM cells from the mobile terminals by a plurality of base stations and transferring the ATM cells from the base stations to the mobile switching stations;

comparing, in the respective mobile switching stations, received signal intensities in the cell header parts of the ATM cells received from the base stations;

switching the base stations from one base station to another base station having a larger received signal intensity;

instructing the mobile terminals to switch a communication channel from one base station to said other base station; and

comparing, in the mobile switching stations, cell numbers of the ATM cells which are received from the mobile terminal via the base stations, and discarding duplicates of the ATM cells having the same cell number.

6. The mobile communication control method as claimed in claim 5, which further comprises the steps of:

controlling timings from the base stations so that a plurality of mobile terminals using the same communication channel within a service area of the base stations transmits the ATM cells at different transmission timings.

7. The mobile communication control method as claimed in claim 5, which further comprises the steps of:

setting, in the mobile terminals, a transmission timing of the respective ATM cells based on a reception timing of the ATM cells from the base stations respectively.

8. The mobile communication control method as claimed in claim 5, which further comprises the steps of:

specifying, in the base stations, a transmission timing of the ATM cells transmitted from the mobile terminals which use the same communication channel within a service area of the base stations, by a control ATM cell including control information.

9. The mobile communication control method as claimed in claim 5, further comprising the step of:

transferring the call control information and the audio information between the mobile terminals and the base stations by ATM cells respectively via a radio channel.

10. A mobile communication control method which controls communication in a mobile communication system including mobile terminals, base stations and mobile switching stations, said mobile communication control method comprising the steps of:

transferring call control information and audio information by the ATM cells between the base stations and the mobile switching stations respectively;

switching the ATM cells in the mobile switching stations depending on tag information in a respective cell header part of the ATM cells, said tag information indicating a structure of a corresponding one of the mobile switching stations;

specifying, in the base stations, a transmission timing of the ATM cells transmitted from the mobile terminals which use the same communication channel within a service area of the base stations, by a control ATM cell including control information;

notifying an accumulated number of ATM cells to be transmitted from the mobile terminals to the base stations by the ATM cells; and

setting, in the base stations, an order of transmission timings of the ATM cells to be transmitted from the mobile terminals based on the accumulated number of ATM cells.

11. A mobile communication control method which controls communication in a mobile communication system including mobile terminals, base stations and mobile switching stations, said mobile communication control method comprising the steps of:

transferring call control information and audio information by the ATM cells between the base stations and the mobile switching stations respectively;

switching the ATM cells in the mobile switching stations depending on tag information in a respective cell header part of the ATM cells, said tag information indicating a structure of a corresponding one of the mobile switching stations;

notifying an accumulated number of ATM cells to be transmitted from the mobile terminals to the base stations by the ATM cells; and

setting, in the base stations, an order of transmission timings of the ATM cells to be transmitted from the mobile terminals based on the accumulated number of ATM cells.