Base station selection system, apparatus and method for a wireless local area network (LAN)

• US 6,697,627 B1
• Filed: 09/29/2000
• Issued: 02/24/2004
• Est. Priority Date: 09/30/1999
• Status: Expired due to Fees

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: Ueno, Tsukasa
• Primary Examiner(s): Chin, Vivian
• Assistant Examiner(s): TRAN, TUAN A
• Application Number:
  US09/672,022
• Time in Patent Office: 1,243 Days
• Field of Search: 455/436-440, 455/450-453, 455/455-456, 455/524-525, 370/329-334, 370/338, 370/341, 370/348
• US Class Current: 455/452.1
• CPC Class Codes: H04W 36/0061 of neighbour cell information

Abstract

A wireless local area network (LAN) has a plurality of wireless base stations, one or more wireless mobile terminal machines communicating over specific frequency bands, and a cabled LAN connecting the wireless base stations. The wireless base station comprises a statistics part to summate statistics data such as connection data of individual wireless mobile terminal machines which leave the communication zone of that base station, and obtaining, from the connection data, data arranging base stations in the order of likeliness of their being connected, and to provide the terminal machine with the base station data thus obtained. The wireless mobile terminal machine comprises a frequency selection apparatus whereby the terminal, when it leaves the communication zone of the current wireless base station, refers to the base stations in the order of likeliness of their being connected, and selects appropriate frequencies for voice communication according to the base stations'"'"' selection priority.

Claims

1. A base station selection system for a wireless local area network (LAN), useful for a communication system based on a wireless LAN comprising a plurality of wireless base stations, one or more wireless mobile terminal machines to practice communication using specific frequency bands, and a cabled LAN connecting the wireless base stations, wherein:

the wireless base station comprises a statistics part to summate statistics data such as connection data of individual wireless mobile terminal machines which leave the communication zone of that base station to enter the communication zones of other wireless base stations, and a means to obtain, from the connection data of each of the above terminal machines, base station data arranging base stations to be likely connected at the next moment in the order of likeliness of their being connected, and to provide the terminal machine with the base station data thus obtained;

the wireless mobile terminal machine comprises a frequency selection part whereby it is possible for the terminal, when it enters into the communication zone of

another wireless base station, to refer to the base station data arranging base stations in the order of likeliness of their being connected, and select an appropriate frequency for voice communication according to the base station to be most likely connected at the next moment.

2. A base station selection system for a wireless LAN as described in claim 1 wherein:

the wireless base station comprises a receiving part to obtain connection data of a terminal machine which has entered its communication zone, and been given communication permission, and a transmitting part to transmit the connection data thus obtained to the base station previously connected with that terminal machine through the cabled LAN.

3. A base station selection system for a wireless LAN as described in claim 2 wherein:

the base station apparatus comprises a data managing

part to update the statistics data regarding the connection of terminals under its coverage based on the connection data sent successively by the previously connected base stations, and to obtain therefrom, for those individual terminals, the likeliness of their being connected with other base stations after they leave the present base station, the connection data including data combining the identification numbers of the other base stations likely to be connected and their frequencies, as well as the identification number of the present base station and its frequency.

4. A base station selection system for a wireless LAN as described in claim 3 wherein:

the wireless base station comprises a use frequency switching circuit to set a frequency to be used in its communication zone, a base station switching data receiving circuit to receive base station switching data from terminals, a base station switching data transmitting circuit to transmit the switching data to mobile terminals within its communication zone, a selection priority transmitting circuit, a base station switching data receiving circuit to receive the base station switching data from other base stations via the cabled LAN connecting the wireless base stations, a terminal/base station data managing portion, a radio communication circuit to communicate data with terminal machines, and a via-network communication circuit to communicate data via the cabled LAN.

5. A base station selection system for a wireless LAN as described in claim 3 wherein:

the wireless terminal machine further comprises a use frequency switching circuit to choose a frequency to be used for communication with a base station, a base station data receiving circuit to receive base station data from the base station whose communication zone it is in, a selection priority receiving circuit, a base station switching data managing portion, a base station switching data transmitting portion, and radio communication circuit to communicate data with a base station.

6. A base station selection system for a wireless LAN as described in claim 3 wherein:

the statistics data updated by the wireless base station apparatus includes, in addition to the statistics data of the terminal machines leaving the communication

zone of the base station in question, and of the terminal machines newly entering the same communication zone, the passage time of those terminals and data regarding other attributes of that base station.

7. A base station selection system for a wireless LAN as described in claim 3, wherein:

the statistics data updated by the wireless base station apparatus further comprises the information regarding a communication agent to support a high ordered communication protocol installed in the wireless base station to be most likely connected at the next moment.

8. A base station selection system for a wireless LAN as described in claim 1 wherein:

the wireless base station apparatus further comprises an identifying part to identify the use frequencies of adjacent base stations by referring to the statistics data updated based on the connection data provided by other wireless base stations, and a frequency adjusting part to choose a frequency based on the knowledge thus obtained to

avoid thereby interference from adjacent base stations.

9. A base station selection method for a wireless local area network (LAN), useful for a communication system based on a wireless LAN comprising a plurality of wireless base stations, one or more wireless mobile terminal machines to practice communication using specific frequency bands, and a cabled LAN connecting the wireless base stations comprising the steps of:

summating statistics data such as connection data of individual wireless mobile terminal machines which leave the communication zone of that base station to enter the communication zones of other wireless base stations;

obtaining from the connection data of each of the above terminal machines, base station data arranging base stations to be likely connected at the next moment in the order of likeliness of their being connected; and

providing the terminal machine with the base station data thus obtained.

10. A base station selection method for a wireless local area network (LAN) as described in claim 9, further comprising the steps of;

frequency selecting whereby it is possible for the terminal, when it enters into the communication zone of another wireless base station;

referring to the base station data arranging base stations in the order of likeliness of their being connected; and

selecting an appropriate frequency for voice communication according to the base station to be most likely connected at the next moment.

11. A base station selection method for a wireless LAN as described in claim 10 also comprising:

obtaining connection data of a terminal machine which has entered its communication zone, and been given communication permission; and

transmitting the connection data thus obtained to the base station previously connected with that terminal machine through the cabled LAN.

12. A base station selection method for a wireless LAN as described in claim 11 further comprising the steps of:

updating the statistics data regarding the connection of terminals under its coverage based on the connection data sent successively by the previously connected base stations;

obtaining therefrom, for those individual terminals, the likeliness of their being connected with other base stations after they leave the present base station, wherein the connection data including data combining the identification numbers of the other base stations likely to be connected and their frequencies, as well as the identification number of the present base station and its frequency.

13. A base station selection method for a wireless LAN as described in claim 12 also comprising the steps of:

setting a frequency to be used in its communication zone;

receiving base station switching data from terminals;

transmitting the switching data to mobile terminals within its communication zone;

selection priority transmitting;

base station switching data receiving to receive the base station switching data from other base stations via the cabled LAN connecting the wireless base stations;

terminal/base station data managing;

radio communicating to communicate data with terminal machines; and

communicating data via the cabled LAN.

14. A base station selection method for a wireless LAN as described in claim 13 also comprising the step of:

frequency switching to choose a frequency to be used for communication with a base station;

base station data receiving to receive base station data from the base station whose communication zone it is in;

selection priority receiving base station switching data managing;

base station switching data transmitting; and

radio communicating to communicate data with a base station.

15. A base station selection method for a wireless LAN as described in claims 14 also comprising the steps of:

identifying the use frequencies of adjacent base stations by referring to the statistics data updated based on the connection data provided by other wireless base stations; and

frequency adjusting to choose a frequency based on the knowledge thus obtained to avoid thereby interference from adjacent base stations.