Wireless base station apparatus and wireless communication control method

• US 7,937,111 B2
• Filed: 10/16/2007
• Issued: 05/03/2011
• Est. Priority Date: 04/30/2004
• Status: Active Grant

• Current Assignee: NTT Docomo Incorporated (Nippon Telegraph and Telephone Corporation)
• Original Assignee: NTT Docomo Incorporated (Nippon Telegraph and Telephone Corporation)
• Inventors: Usuda, Masafumi, Hanaki, Akihito, Ishii, Hiroyuki, Imamura, Yoshimasa
• Primary Examiner(s): D AGOSTA, STEPHEN M
• Application Number:
  US11/873,148
• Publication Number:
  US 20080039145A1
• Time in Patent Office: 1,295 Days
• Field of Search: 455/62, 455/63.1, 455/67.13, 455/450, 455/501, 455/504, 455/505, 455/561, 455/562.1, 370/317, 370/322, 370/329, 370/341
• US Class Current: 455/561
• CPC Class Codes: H04B 1/1027 assessing signal quality or detecting noise/interference for the received signal
• CPC Class Codes: H04L 1/0009 by adapting the channel coding H04L1/1812 takes precedence
• CPC Class Codes: H04L 1/0026 Transmission of channel quality indication
• CPC Class Codes: H04L 1/16 in which the return channel carries supervisory signals, e.g. repetition request signals
• CPC Class Codes: H04L 1/20 using signal quality detector
• CPC Class Codes: H04W 28/06 Optimizing the usage of the radio link, e.g. header compression, information sizing , discarding information system modifying transmission characteristic according to link quality by modifying frame length H04L1/0007; dynamic adaptation of the packet size for flow control or congestion control H04L47/365
• CPC Class Codes: H04W 72/542 using measured or perceived quality
• CPC Class Codes: H04W 88/08 Access point devices

Abstract

A wireless base station apparatus (100) used in a wireless communications system includes a statistical processing unit (140) that performs statistical processing on downlink radio quality information reported from a wireless communications terminal device; a radio quality information offsetting unit (160) that adjusts the statistically processed downlink radio quality information based on a downlink transmission confirmation (ACK/NACK/DTX) message transmitted from the wireless communications terminal device and a required downlink quality; a transport format determination unit (170) that determines a downlink transport format based on the statistically processed radio quality information or the offset-adjusted radio quality information; and a transmitting unit (111) that transmits a downlink channel with the determined downlink transport format.

Claims

1. A wireless base station apparatus configured to perform wireless communication with a wireless communications terminal device, the apparatus comprising:

a radio quality information offsetting unit configured to adjust downlink radio quality information reported from the wireless communications terminal device, to produce offset-adjusted radio quality information, such that a block error rate becomes a target level, based on a downlink transmission confirmation message transmitted from the wireless communication terminal and a required downlink quality;

a transport format determination unit configured to determine a downlink transport format based on the offset-adjusted radio quality information; and

a transmitting unit configured to transmit on a downlink channel with the determined downlink transport format, wherein

the radio quality information offsetting unit is further configured to produce the offset-adjusted radio quality information, in which an offset value is increased when the downlink transmission confirmation message transmitted from the wireless communications terminal includes an ACK, produce the offset-adjusted radio quality information, in which the offset value is decreased when the downlink transmission confirmation message transmitted from the wireless communications terminal includes a NACK, and produce the offset-adjusted radio quality information, in which the offset value is unchanged when the downlink transmission confirmation message transmitted from the wireless communications terminal includes a DTX.

2. The wireless base station apparatus of claim 1, wherein the radio quality information offsetting unit is further configured to adjust the downlink radio quality information reported from the wireless communications terminal device based on an average of a plurality of radio quality information indicators reported from the wireless communication terminal device.

3. The wireless base station apparatus of claim 1, wherein the radio quality information offsetting unit is further configured to adjust the downlink radio quality information reported from the wireless communications terminal device based on which one of the ACK, the NACK, or the DTX is included in the downlink transmission confirmation message transmitted from the wireless communications terminal.

4. The wireless base station apparatus of claim 1, wherein the radio quality information offsetting unit is further configured to adjust the target level based on a priority class.

5. The wireless base station apparatus of claim 1, wherein the radio quality information offsetting unit is further configured to adjust the target level based on a service type.

6. The wireless base station apparatus of claim 1, wherein the radio quality information offsetting unit is further configured to adjust the target level based on a current communication cell.

7. The wireless base station apparatus of claim 1, wherein the radio quality information offsetting unit is further configured to adjust the target level based on a contract type.

8. A wireless base station apparatus configured to perform wireless communication with a wireless communication terminal device, the apparatus comprising:

a radio quality information offset unit configured to adjust downlink radio quality information reported from the wireless communication terminal device, to produce offset-adjusted radio quality information, such that a block error rate becomes a target level, based on a downlink transmission confirmation message transmitted from the wireless communications terminal and a required downlink quality;

a transport format determination unit configured to determine a downlink transport format based on the offset-adjusted radio quality information; and

a transmitting unit configured to transmit a downlink channel with the determined downlink transport format, wherein

the radio quality information offsetting unit is further configured to increase an offset value by a first value multiplied by a selected step size when an ACK is included in the downlink transmission configuration message and decrease an offset value by a second value multiplied by the selected step size when the NACK is included in the downlink transmission confirmation message, where the first value is a target BLER, the second value is 1 minus the target BLER, and BLER denotes the block error rate.

9. The wireless base station apparatus of claim 8, wherein the radio quality information offsetting unit is further configured to select the selected step size based on which one of the ACK, the NACK, or a DTX is included in the downlink transmission confirmation message transmitted from the wireless communications terminal.

10. The wireless base station apparatus of claim 8, wherein the radio quality information offsetting unit is further configured to select the selected step size based on a priority class.

11. The wireless base station apparatus of claim 8, wherein the radio quality information offsetting unit is further configured to select the selected step size based on a service type.

12. The wireless base station apparatus of claim 8, wherein the radio quality information offsetting unit is further configured to select the selected step size based on a current communication cell.

13. The wireless base station apparatus of claim 8, wherein the radio quality information offsetting unit is further configured to select the selected step size based on a contract type.

14. A wireless communication method between a wireless base station apparatus and a wireless communications terminal device, comprising:

receiving, by a receiver, downlink radio quality information from the wireless communication terminal device;

adjusting the downlink radio quality information to produce offset-adjusted radio quality information, such that a block error rate becomes a target level, based on a downlink transmission confirmation message transmitted from the wireless communications terminal and a required downlink quality;

determining, a downlink transport format based on the offset-adjusted radio quality information

wherein the adjusting further includes producing the offset-adjusted radio quality information such that an offset value is increased when the downlink transmission confirmation message transmitted from the wireless communications terminal includes an ACK, producing the offset value such that the offset value is decreased when the downlink transmission confirmation message transmitted from the wireless communications terminal includes a NACK, and producing the offset value such that the offset value is unchanged when the downlink transmission confirmation message transmitted from the wireless communications terminal includes a DTX.