WIRELESS COMMUNICATION APPARATUS AND WIRELESS COMMUNICATION METHOD USING VARIABLE TRANSMISSION RATE

• US 20090092110A1
• Filed: 09/29/2008
• Published: 04/09/2009
• Est. Priority Date: 10/05/2007
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Taki, Daisuke, Sekiya, Masahiro
• Granted Patent: US 8,089,868 B2
• Time in Patent Office: Days
• US Class Current: 370/338
• CPC Class Codes: H04L 1/0002 by adapting the transmission rate
• CPC Class Codes: H04L 1/003 Adaptive formatting arrangements particular to signalling, e.g. variable amount of bits
• CPC Class Codes: H04L 1/1854 Scheduling and prioritising arrangements
• 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 28/22 Negotiating communication rate

Abstract

A wireless communication apparatus includes a transmission section and a control section. The transmission section transmits data using wireless communication. The control section controls a transmission rate for the transmission section. The control section limits data size of data to be transmitted to at most a prescribed value and requests a transmission acknowledgement, during a period from immediately after a change in the transmission rate until number of times that the transmission section transmits data reaches a prescribed number of times.

Claims

1. A wireless communication apparatus comprising:

a transmission section which transmits data using wireless communication; and

a control section which controls a transmission rate for the transmission section, the control section limiting data size of data to be transmitted to at most a prescribed value and requesting a transmission acknowledgement, during a period from immediately after a change in the transmission rate until number of times that the transmission section transmits data reaches a prescribed number of times.

2. The apparatus according to claim 1, further comprising a frame generation section which generates a frame of the data to be transmitted and which aggregates a plurality of the frames,

wherein the transmission section transmits the frame generated by the frame generation section or the plurality of frames aggregated by the frame generation section, and

during the period until the number of times that the frame is transmitted reaches the prescribed number of times, the control section prohibits the frame generation section from aggregating the frames, while instructing the frame generation section to generate the frame as a frame requesting the transmission acknowledgement.

3. The apparatus according to claim 2, wherein the control section includes:

a counter which starts counting the number of times that the frame is transmitted, immediately after the change in the transmission rate;

a comparison section which compares a counter value in the counter with the prescribed number of times; and

an instruction section which prohibits the frame generation section from aggregating the frames if the comparison by the comparison section shows that the counter value is less than the prescribed number of times.

4. The apparatus according to claim 2, wherein the frame generation section includes:

a generation section which generates the frame;

an aggregation section which aggregates a plurality of the frames generated by the frame generation section; and

a setting section which sets the transmission acknowledgement for the single frame generated by the frame generation section or a plurality of the frames aggregated by the aggregation section,

wherein during the period until the number of times that the frame is transmitted reaches the prescribed number of times, the control section prohibits the aggregation section from aggregating the frames, while instructing the setting section to set the transmission acknowledgement for the frames.

5. The apparatus according to claim 2, wherein the aggregated plurality of frames are managed on the basis of the same traffic ID.

6. The apparatus according to claim 1, further comprising a frame generation section which generates a frame of data received from a data generation section generating the data to be transmitted,

wherein the transmission section transmits the frame generated by the frame generation section, and

during the period until the number of times that the frame is transmitted reaches the prescribed number of times, the control section instructs the data generation section to limit the data size of the data to be transmitted to at most the prescribed value, while instructing the frame generation section to generate the frame as a frame requesting the transmission acknowledgement.

7. The apparatus according to claim 6, wherein the transmission section transmits one of the frames during every transmission without aggregating the frames.

8. The apparatus according to claim 6, wherein the control section includes:

the counter which starts counting the number of times that the frame is transmitted, immediately after the change in the transmission rate;

the comparison section which compares a counter value in the counter with the prescribed number of times; and

an instruction section which instructs the data generation section to limit the data size of the transmission data to at most the prescribed value if the comparison by the comparison section shows that the counter value is less than the prescribed number of times.

9. The apparatus according to claim 6, wherein the frame generation section includes:

a generation section which receives the transmission data from the data generation section to generate the frame; and

a setting section which sets the transmission acknowledgement for the single frame generated by the frame generation section,

wherein during the period until the number of times that the frame is transmitted reaches the prescribed number of times, the control section instructs the setting section to set the transmission acknowledgement for the frame.

10. The apparatus according to claim 6, wherein the control section limits the data size to at most the prescribed value to set a frame length of the frame generated by the frame generation section to at most a predetermined given value.

11. The apparatus according to claim 1, wherein the control section uses a packet error rate as an index to determine the transmission rate.

12. The apparatus according to claim 2, wherein the frame is a MAC protocol data unit.

13. The apparatus according to claim 6, wherein the frame is the MAC protocol data unit.

18. The method according to claim 11, wherein the transmission rate is determined using a packet error rate as an index.

14. A wireless communication method comprising:

changing a data transmission rate according to a status of a transmission path;

starting counting number of times that data is transmitted, immediately after a change in a transmission rate; and

limiting data size of data to be transmitted to at most a prescribed value and requesting transmission acknowledgement, during a period until the number of times that the data is transmitted reaches a prescribed number of times.

15. The method according to claim 14, wherein the data to be transmitted is assembled into a frame for transmission, and

by preventing frames from being aggregated during the period until the number of times that the frame is transmitted reaches the prescribed number of times, the data size of the data to be transmitted is limited to at most the prescribed value,

the method further comprising permitting aggregation of the frames after the number of times that the frame is transmitted reaches the prescribed number of times.

16. The method according to claim 14, wherein the data to be transmitted is assembled into a frame for transmission, and

during the period until the number of times that the frame is transmitted reaches the prescribed number of times, a data generation section generating the data to be transmitted is instructed to limit the data size of the data to be transmitted to at most the prescribed value,

the method further comprising permitting data of a data size greater than the prescribed value to be generated after the number of times that the frame is transmitted reaches the prescribed number of times.

17. The method according to claim 16, wherein one of the frames is transmitted during every transmission without being aggregated.

19. The method according to claim 15, wherein the frame is a MAC protocol data unit.

20. The method according to claim 16, wherein the frame is the MAC protocol data unit.