Telecommunications system, base station thereof and telecommunications method

• US 7,805,167 B1
• Filed: 03/15/2000
• Issued: 09/28/2010
• Est. Priority Date: 03/16/1999
• Status: Expired due to Fees

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Esmailzadeh, Riaz
• Primary Examiner(s): Urban; Edward F.
• Assistant Examiner(s): NGUYEN, THUAN T
• Application Number:
  US09/525,901
• Time in Patent Office: 3,849 Days
• Field of Search: 455/562.1, 455/452, 455/453, 455/463, 455/518, 455/519, 455/561, 455/431, 455/452.1, 455/452.2
• US Class Current: 455/562.1
• CPC Class Codes: H01Q 1/246 specially adapted for base stations
• CPC Class Codes: H01Q 3/2605 Array of radiating elements provided with a feedback control over the element weights, e.g. adaptive arrays
• CPC Class Codes: H04B 7/0851 using training sequences or error signal minimizing error signal H04B7/0854
• CPC Class Codes: H04W 16/28 using beam steering
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A wireless telecommunications system capable of transmitting desired information to a plurality of mobile stations efficiently is adapted to transmit the information to the plurality of mobile stations by forming a signal beam that covers these mobile stations simultaneously. Since information can thus be sent to a plurality of mobile stations at the same time, it is possible to send information in a highly efficient. In addition, because transmission power can be reduced, interference acting upon other mobile stations can be suppressed.

Claims

1. A method of broadcasting information to mobile stations within a wireless telecommunications system, wherein said system includes a radio base station having an adaptive array antenna having a plurality of antenna elements, said method comprising the steps of:

determining the geographic position of a plurality of mobile stations subscribed to receive certain broadcast information;

generating a multicast data transmission signal including said broadcast information; and

feeding said multicast data transmission signal to each of said plurality of antenna elements of said adaptive array antenna, wherein the amplitude and phase of said signal delivered to each of said plurality of antenna elements is adjusted as a function of said geographic position of said plurality of mobile stations, whereby a signal beam is formed having a beam width sufficient to cover only the area substantially bounded by the geographic locations of said plurality of mobile stations.

2. The method of claim 1, wherein said step of determining the geographic position of said plurality of mobile stations is performed for each of said mobile stations in response to receiving a signal from a mobile station requesting receipt of said broadcast information.

3. The method of claim 1, wherein said amplitude and phase of said signal delivered to each of said plurality of antenna elements are a function of a signal received from each of said plurality of mobile stations.

4. The method of claim 3, wherein said signal received from each of said plurality of mobile stations comprises data identifying the geographic position of said mobile station.

5. The method of claim 4, wherein said data identifying said geographic position is obtained by said mobile station from a Global Positioning System (GPS) satellite.

6. A system for broadcasting information to mobile stations within a wireless telecommunications network, wherein said network includes a radio base station having an adaptive array antenna having a plurality of antenna elements, said system comprising:

means for determining the geographic position of a plurality of mobile stations subscribed to receive certain broadcast information;

means for generating a multicast data transmission signal including said broadcast information; and

means for feeding said multicast data transmission signal to each of said plurality of antenna elements of said adaptive array antenna, wherein the amplitude and phase of said signal delivered to each of said plurality of antenna elements is adjusted as a function of said geographic position of said plurality of mobile stations, whereby a signal beam is formed having a beam width sufficient to cover only the area substantially bounded by the geographic locations of said plurality of mobile stations.

7. The system of claim 6, wherein said means for determining the geographic position of said plurality of mobile stations determines said position for each of said mobile stations in response to receiving a signal from a mobile station requesting receipt of said broadcast information.

8. The system of claim 6, wherein said amplitude and phase of said signal delivered to each of said plurality of antenna elements are a function of a signal received from each of said plurality of mobile stations.

9. The system of claim 8, wherein said signal received from each of said plurality of mobile stations comprises data identifying the geographic position of said mobile station.

10. The system of claim 9, wherein said data identifying said geographic position is obtained by said mobile station from a Global Positioning System (GPS) satellite.