Apparatus for time division multi-sector wireless LAN

• US 20040171407A1
• Filed: 01/26/2004
• Published: 09/02/2004
• Est. Priority Date: 02/28/2003
• Status: Active Grant

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Ninomiya, Teruhisa
• Granted Patent: US 7,299,072 B2
• Time in Patent Office: Days
• US Class Current: 455/561
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks
• CPC Class Codes: H04W 88/08 Access point devices

Abstract

An apparatus for a wireless base station is adapted to communicate with a plurality of wireless terminals in a plurality of sectors and comprises a communication control unit, and a plurality of transceivers associated with the sectors, respectively. The transceivers have respective directive antennas associated with the respective sectors. During a first period of time, the communication control unit enables one or more of the plurality of transceivers that are associated with respective one or more of the plurality of sectors that are not adjacent to each other, to communicate with wireless terminals, and the communication control unit disables remaining one or more transceivers other than the enabled one or more transceivers, from communicating with wireless terminals. During a second period of time subsequent to the first period of time, the communication control unit enables further one or more of the plurality of transceivers that are associated with respective further one or more of the plurality of sectors that are not adjacent to each other, to communicate with wireless terminals, in which the further one or more transceivers is disabled in the first period of time from communicating, and the control unit disables further remaining one or more transceivers other than the enabled further one or more transceivers, from communicating with wireless terminals.

Claims

1. An apparatus for a wireless base station adapted to communicate with a plurality of wireless terminals in a plurality of sectors, said apparatus comprising:

a communication control unit, and

a plurality of transceivers associated with said sectors, respectively,

said transceivers having respective directive antennas associated with said respective sectors, wherein,

during a first period of time, said communication control unit enables one or more of said plurality of transceivers that are associated with respective one or more of said plurality of sectors that are not adjacent to each other, to communicate with wireless terminals, and said communication control unit disables remaining one or more transceivers other than said enabled one or more transceivers, from communicating with wireless terminals, and wherein, and,

during a second period of time subsequent to said first period of time, said communication control unit enables further one or more of said plurality of transceivers that are associated with respective further one or more of said plurality of sectors that are not adjacent to each other, to communicate with wireless terminals, said further one or more transceivers being disabled in said first period of time from communicating, and said communication control unit disables further remaining one or more transceivers other than said enabled further one or more transceivers, from communicating with wireless terminals.

2. The apparatus according to claim 1, wherein, a predetermined length of time before the change to said second period of time, said transceiver which is enabled to communicate starts detection of a transmitted RF signal in a corresponding sector, and broadcasts a packet indicative of disabling of transmission during said second period of time, when said transmitted RF-signal is not received.

3. The apparatus according to claim 1, wherein, before the change to said second period of time, said transceiver which is enabled to communicate broadcasts a packet containing indication of a length of said second period of time to wireless terminals in a corresponding sector.

4. The apparatus according to claim 1, wherein, during a third period of time before said first period of time, said communication control unit in all of said sectors causes all of said transceivers to communicate with said plurality of wireless terminals, determines locations of said wireless terminals in the sectors, in accordance with identification codes of said wireless terminals and with identifications of said transceivers which receive said identification codes, and stores, in a location management table, information indicating which wireless terminals are located in each sector.

5. The apparatus according to claim 1, wherein, during a third period of time, said communication control unit causes all of said transceivers to transmit, in all of said sectors, a packet addressed to one of said wireless terminals, whose current location in the sectors is unknown.

6. The apparatus according to claim 1, wherein, during said first period of time, in one of said plurality of sectors, when one of said plurality of transceivers receives an identification code of one of said plurality of wireless terminals which has been located in another sector, from said one terminal, said communication control unit stores said identification code of said one wireless terminal into said location management table in association with said one sector.

7. The apparatus according to claim 1, wherein said transceivers transmit and receive signals in the same frequency band.

8. A wireless terminal adapted to communicate with a wireless base station in any one of a-plurality of sectors, said wireless terminal comprising:

a control unit for communicating with said wireless base station during a first period of time, and for receiving a packet containing a description representative of a length of a second period of time subsequent to said first period of time, and for disabling transmission during said second period of time.

9. A program product for an apparatus for a wireless base station adapted to communicate with a plurality of wireless terminals in a plurality of sectors, said program being operable to effect the steps of:

during a first period of time, enabling one or more of said plurality of transceivers that are associated with respective one or more of said plurality of sectors that are not adjacent to each other, to communicate with wireless terminals, and disabling remaining one or more transceivers other than said enabled one or more transceivers, from communicating with wireless terminals; and

,

during a second period of time subsequent to said first period of time, enabling further one or more of said plurality of transceivers that are associated with respective further one or more of said plurality of sectors that are not adjacent to each other, to communicate with wireless terminals, said further one or more transceivers being disabled in said first period of time from communicating, and disabling further remaining one or more transceivers other than said enabled further one or more transceivers, from communicating with wireless terminals.

10. A method for communication in an apparatus for a wireless base station adapted to communicate with a plurality of wireless terminals in a plurality of sectors, said method comprising the steps of:

during a first period of time, enabling one or more of said plurality of transceivers that are associated with respective one or more of said plurality of sectors that are not adjacent to each other, to communicate with wireless terminals, and disabling remaining one or more transceivers other than said enabled one or more transceivers, from communicating with wireless terminals; and

,

during a second period of time subsequent to said first period of time, enabling further one or more of said plurality of transceivers that are associated with respective further one or more of said plurality of sectors that are not adjacent to each other, to communicate with wireless terminals, said further one or more transceivers being disabled in said first period of time from communicating, and disabling further remaining one or more transceivers other than said enabled further one or more transceivers, from communicating with wireless terminals.

11. A method for communication in a wireless terminal adapted to communicate with a wireless base station in any one of a plurality of sectors, said method comprising:

communicating with said wireless base station during a first period of time,

receiving a packet containing a description representative of a length of a second period of time subsequent to said first period of time, and

disabling transmission during said second period of time.