WIRELESS COMMUNICATION SYSTEM

• US 20100046462A1
• Filed: 11/04/2009
• Published: 02/25/2010
• Est. Priority Date: 03/22/2005
• Status: Abandoned Application

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Kuwahara, Mikio, Fujishima, Kenzaburo, UWANO, Koki, Taira, Masanori
• Application Number:
  US12/611,964
• Publication Number:
  US 20100046462A1
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04B 7/0408 using two or more beams, i.e. beam diversity
• CPC Class Codes: H04B 7/0617 for beam forming
• CPC Class Codes: H04W 16/26 Cell enhancers or enhancement, e.g. for tunnels, building shadow
• CPC Class Codes: H04W 16/28 using beam steering
• CPC Class Codes: H04W 28/10 Flow control between communication endpoints
• CPC Class Codes: H04W 64/006 with additional information processing, e.g. for direction or speed determination

Abstract

Wireless communication arrangements including: performing scheduling of transmitting signal to each of the mobile stations so that interference of radio waves sent from each of the remote units to each of the mobile stations can be suppressed based on priority level of the mobile station and the interference area information; generating information to control the direction-variable antenna of each of the plurality of remote units, so that the corresponding remote unit forms beam according to scheduling result; and transmitting the information to control the direction-variable antenna to the plurality of remote units.

Claims

1. A wireless communication method in a wireless communication system comprising:

a plurality of remote units for transmitting and receiving wireless signals with a plurality of mobile stations, each of the plurality of the remote units including a direction-variable antenna of which directivity varies with an electric signal supplied to a plurality of antenna elements;

a central base station connected with the plurality of remote units, for transmitting signals from the plurality of mobile stations through the plurality of remote units to a network side and receiving signals for the plurality of mobile stations from the network side, and performing scheduling of transmitting signals to the plurality of mobile stations;

wherein the central base station executing operations of;

storing an identification and an area information of a remote unit in which each mobile station is placed, for the plurality of remote units connected with the central base station;

storing a plurality of other area information causing interference with a certain area of a certain remote unit corresponding to each area of a remote unit;

performing scheduling of transmitting a signal to each of the mobile stations so that interference of radio waves sent from each of the remote units to each of the mobile stations can be suppressed based on priority level of the mobile station and the interference area information;

generating information to control the direction-variable antenna of each of the plurality of remote units, so that the corresponding remote unit forms a beam according to scheduling result; and

transmitting the information to control the direction-variable antenna to the plurality of remote units.

2. A wireless communication method according to claim 1, wherein the central base station holds electric signals to be supplied to the direction-variable antenna as a plurality of beam patterns, and the directivity is changed by switching the beam pattern as selected in accordance with the position of the mobile station.

3. A wireless communication method according to claim 2, wherein the central base station estimates the position of the mobile station by predicting the direction in which radio waves come from the mobile station, and determines the beam pattern to be sent to the mobile station.

4. A wireless communication method according to claim 2, wherein each mobile station receives radio waves of all beam patterns from the remote units and notifies the central base station of a beam received with good quality, and the central base station determines the beam pattern to be sent to the mobile station.

5. A wireless communication method according to claim 3, wherein the central base station performs centralized management of the beam patterns to be sent to all the mobile stations.

6. A wireless communication method according to claim 1, wherein

the performing scheduling selects such a mobile station that a transmitted beam will not cause strong interference, in accordance with the priority levels of the mobile stations and based on the area information;

and

a combination of mobile stations are determined so that interference will not occur between radio waves sent by the remote units.

7. A wireless communication method according to claim 1, wherein each mobile station measures radio waves sent from the remote unit, determines a beam pattern causing interference, and notifies the central base station of interference area information;

and

the central base station, in accordance with the notified interference area information, determines such a combination of mobile stations that radio waves sent from the remote units will not cause interference.

8. A wireless communication method according to claim 7, wherein beam patterns of radio waves to be checked for interference are selected in accordance with the communicating position of each mobile station, in the radio wave measurement of the mobile station.

9. A wireless communication method according to claim 4, wherein the central base station performs centralized management of the beam patterns to be sent to all the mobile stations.