Radio base station system and central control station with unified transmission format

• US 7,072,586 B2
• Filed: 12/27/2000
• Issued: 07/04/2006
• Est. Priority Date: 12/28/1999
• Status: Expired due to Fees

• Current Assignee: NTT Docomo Incorporated (Nippon Telegraph and Telephone Corporation)
• Original Assignee: NTT Docomo Incorporated (Nippon Telegraph and Telephone Corporation)
• Inventors: Yamao, Yasushi, Suda, Hirohito, Aburakawa, Yuji
• Primary Examiner(s): BELLO, AGUSTIN
• Application Number:
  US09/748,259
• Publication Number:
  US 20020030870A1
• Time in Patent Office: 2,015 Days
• Field of Search: 398115-117, 398118-131, 398135-139, 398/167, 398/167.5
• US Class Current: 398/115
• CPC Class Codes: H04B 10/25753 Distribution optical network, e.g. between a base station and a plurality of remote units

Abstract

A central control station, which controls radio base stations connected thereto via radio links and optical fiber links, includes a demultiplexing unit which demultiplexes signals supplied from an upper-level station, signal conversion units which convert the respective demultiplexed signals into converted signals having a unified transmission format, and a distribution unit which distributes the converted signals to the radio links and the optical fiber links.

Claims

1. A central control station configured to control base stations connected thereto, and is connected to an upper-level station, said central control station comprising:

a demultiplexing unit configured to demultiplex a signal supplied from the upper-level station to generate a plurality of demultiplexed signals for transmission to the base stations;

analog-to-digital converters coupled to said demultiplexing unit, configured to convert the respective demultiplexed signals from digital to analog, so as to output respective analog signals;

analog signal conversion units which are coupled to said analog-to-digital converters, configured to convert the respective analog signals into converted analog signals having a common transmission format;

transceiver units including at least one radio transceiver unit linked to a corresponding one of the base stations via a radio link and at least one optical transceiver unit linked to a corresponding one of the base stations via an optical fiber link; and

a distribution unit which is provided between said analog signal conversion units and said transceiver units, configured to provide changeable interconnections between said analog signal conversion units and said transceiver units for the converted analog signals having the common transmission format, said common transmission format enabling compatibility between radio links and optical fiber links with respect to the changeable interconnections.

2. The central control station as claimed in claim 1, wherein said analog signal conversion units include a modulation/demodulation unit.

3. The central control station as claimed in claim 1, wherein said analog signal conversion units include a modulation/demodulation unit and a radio frequency conversion unit.

4. The central control station as claimed in claim 1, wherein said analog signal conversion units include a base-band modulation/demodulation unit.

5. A central control station which controls base stations connected thereto, and is connected to an upper-level station, said central control station comprising:

a demultiplexing unit configured to demultiplex a signal supplied from the upper-level station to generate a plurality of demultiplexed signals for transmission to the base stations;

digital-to-analog converters coupled to said multiplexing unit, configured to convert the respective demultiplexed signals from digital to analog, so as to output respective analog signals;

analog signal conversion means configured to convert the respective analog signals into converted analog signals having a common transmission format, said signal conversion means being coupled to said digital-to-analog converters;

transceiver units including at least one radio transceiver unit linked to a corresponding one of the base stations via a radio link and at least one optical transceiver unit linked to a corresponding one of the base stations via an optical fiber link; and

a distribution unit which is provided between said analog signal conversion means and said transceiver units configured to provide changeable interconnections between said analog signal conversion means and said transceiver units for the converted analog signals having the common transmission format, said common transmission format enabling compatibility between radio links and optical fiber links with respect to the changeable interconnections.

6. The central control station as claimed in claim 5, wherein said analog signal conversion means includes a modulation/demodulation unit.

7. The central control station as claimed in claim 5, wherein said analog signal conversion means includes a modulation/demodulation unit and a radio frequency conversion unit.

8. The central control station as claimed in claim 5, wherein said analog signal conversion means includes a base-band modulation/demodulation unit.

9. A method for controlling base stations connected to an upper-level station in a mobile communication system, the method comprising:

demultiplexing a signal supplied from the upper-level station to generate a plurality of demultiplexed signals for transmission to the base stations;

first converting the respective demultiplexed signals from digital to analog to output respective analog signals, after said demultiplexing;

second converting the respective analog signals into converted analog signals having a common transmission format, after said first converting;

distributing said converted analog signals via changeable interconnections to transceiver units including at least one radio transceiver unit linked to a corresponding one of the base stations via a radio link and at least one optical transceiver unit linked to a corresponding one of the base stations via an optical fiber link, said common transmission format enabling compatibility between radio links and optical fiber links with respect to the changeable interconnections, after said second converting; and

transmitting said distributed signals to the corresponding ones of the base stations via the radio link and the optical fiber link, after said distributing.