Base station device and radio communication method

• US 6,442,405 B1
• Filed: 05/30/2000
• Issued: 08/27/2002
• Est. Priority Date: 10/07/1998
• Status: Expired due to Fees

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Hiramatsu, Katsuhiko, Watanabe, Masatoshi, Uesugi, Mitsuru, Kato, Osamu, Horikawa, Izumi, Miya, Kazuyuki, Iwaoka, Atsushi, Tatsumi, Akinori
• Primary Examiner(s): Chin, Vivian
• Assistant Examiner(s): Lee, John J.
• Application Number:
  US09/555,379
• Time in Patent Office: 819 Days
• Field of Search: 455/562, 455/277.1, 455/101, 455/11.1, 455/125, 455/67.3, 455/561, 455/448, 455/423, 455/132, 455/133, 370/252, 370/335, 370/441, 370/330, 370/345, 375/347, 342/457, 342/378
• US Class Current: 455/562.1
• CPC Class Codes: H04B 7/0408 using two or more beams, i.e. beam diversity
• CPC Class Codes: H04B 7/0491 using two or more sectors, i.e. sector diversity
• CPC Class Codes: H04B 7/086 using weights depending on external parameters, e.g. direction of arrival [DOA], predetermined weights or beamforming
• CPC Class Codes: H04W 16/24 Cell structures
• CPC Class Codes: H04W 88/08 Access point devices
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

Taking into account an optimal reception characteristic of a communication apparatus with variable directivity, the base station apparatus of the present invention has a communication apparatus with variable directivity positively accommodate a communication with a terminal in poor reception conditions, which makes it possible to reduce power of this terminal and reduce interference, thereby increasing the subscriber capacity in the system.

Claims

1. A base station apparatus comprising:

at least one first communicator for carrying out a communication with fixed directivity;

at least one second communicator for carrying out a communication with variable directivity;

an assigner for assigning a communication to said first and second communicators according to a communication condition; and

a communication condition detector for detecting said communication condition, wherein;

said communication condition comprises interference with other terminals, and

said assigner assigns a communication with small interference with other terminals to said first communicator and a communication with large interference with other terminals to said second communicator.

2. The base station apparatus according to claim 1, wherein said second communicator performs a narrower directivity in a communication having a greater interference with other terminals.

3. A base station apparatus comprising:

at least one first communicator for carrying out a communication with fixed directivity;

at least one second communicator for carrying out a communication with variable directivity;

an assigner for assigning a communication to said first and second communicators according to a communication condition; and

a communication condition detector for detecting said communication condition, wherein;

said communication condition comprises a data rate of the reception signal, and

said communication condition detector comprises a rate identifier for measuring said data rate of the reception signal.

4. The base station apparatus according to claim 3, wherein said assigner assigns a communication at a relatively low data rate to said first communicator and a communication at a relatively high data rate said second communicator.

5. The base station apparatus according to claim 3, wherein, when a number of terminals carrying out communications at a relatively high data rate is greater than a number of said second communicators, said assigner preferentially assigns a communication with terminals located far away from said base station among said terminals to said second communicator.

6. The base station apparatus according to claim 5, wherein said communication condition detector comprises a quality measurer for measuring the quality of the reception signal;

and the base station further comprises a determiner for determining said far terminals based on the measurement result from said quality measurer.

7. The base station apparatus according to claim 3, wherein, when the number of terminals carrying out communications at a relatively high data rate is greater than a number of said second communicators, said assigner preferentially assigns a communication with terminals carrying out communications at higher data rate among said terminals to said second communicator.

8. A base station apparatus comprising:

at least one first communicator for carrying out a communication with fixed directivity;

at least one second communicator for carrying out a communication with variable directivity;

an assigner for assigning a communication to said first and second communicators according to a communication condition; and

a communication condition detector for detecting said communication condition, wherein;

said communication condition comprises the quality of the reception signal, and

said communication condition detector comprises a quality measurer for measuring the quality of the reception signal.

9. The base station apparatus according to claim 8, wherein said assigner assigns a communication with relatively poor quality of the reception signal to said second communicator.

10. A communication terminal apparatus carrying out a radio communication with a base station apparatus, said base station apparatus comprising:

at least one first communicator for carrying out a communication with fixed directivity;

at least one second communicator for carrying out a communication with variable directivity;

an assigner for assigning communications to said first and second communicators according to a communication condition; and

a communication condition detector for detecting said communication condition, wherein;

said communication condition comprises interference with other terminals, and

said assigner assigns a communication with small interference with other terminals to said first communicator and a communication with large interference with other terminals to said second communicator.

11. A radio communication method comprising the steps of:

(a) measuring a data rate of a reception signal from a terminal;

(b) deciding whether a communication with said terminal is carried out with a fixed directivity or a variable directivity, based on the measured data rate; and

(c) carrying out said communication with said terminal with said fixed directivity or said variable directivity based on a decision result of step (b).

12. The radio communication method according to claim 11, wherein communication at a relatively low data rate is carried out with said fixed directivity and communication at a relatively high data rate is carried out with said variable directivity.