Frame aggregation in wireless communications networks

• US 7,474,676 B2
• Filed: 09/10/2004
• Issued: 01/06/2009
• Est. Priority Date: 09/10/2004
• Status: Expired due to Fees

• Current Assignee: Mitsubishi Electric Research Laboratories, Inc. (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Electric Research Laboratories, Inc. (Mitsubishi Electric Corporation)
• Inventors: Nagai, Yukimasa, Tao, Zhifeng, Gu, Daqing
• Primary Examiner(s): Pham; Chi H.
• Assistant Examiner(s): Tran; Phuc
• Application Number:
  US10/939,210
• Publication Number:
  US 20060056443A1
• Time in Patent Office: 1,579 Days
• Field of Search: None
• US Class Current: 370/469
• CPC Class Codes: H04L 1/1628 List acknowledgements, i.e. the acknowledgement message consisting of a list of identifiers, e.g. of sequence numbers H04L1/1614 takes precedence
• 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

Abstract

A method aggregates frames to be transmitted over a channel in a wireless network into a single frame. Multiple MSDU frames having identical destination addresses and identical traffic classes, received in the media access control layer from the logical link layer in a transmitting station are aggregated into a single aggregate MPDU frame, which can be transmitted on the channel to a receiving station. In addition, aggregate MSDU frames with different destination addresses and different traffic classes received from the media access control layer can be further aggregated into a single aggregate PPDU frame before transmission.

Claims

1. A method for aggregating frames to be transmitted over a channel in a wireless network, comprising:

receiving from a logical link layer in a transmitting station a plurality of MSDU frames in a media access control layer;

aggregating selected MSDU frames having identical destination addresses and identical traffic classes into a single aggregate MPDU frame;

receiving from the media access control layer in the transmitter a plurality of the aggregate MPDU frames as PSDU frames in a physical layer;

aggregating selected PSDU frames with different destination addresses and different traffic classes into a single aggregate PPDU frame in the physical layer; and

transmitting the single aggregate PPDU frame on the channel of the wireless communication network.

2. The method of claim 1, in which the aggregation of the MSDU frames is during a contention period.

3. The method of claim 1, in which the aggregation of the MSDU frames is during a contention free period.

4. The method of claim 1, in which the aggregation of the PSDU at the physical layer frames is during a contention period.

5. The method of claim 1, in which the aggregate MPDU frame includes the MSDU frames having the identical destination address and the identical traffic class.

6. The method of claim 5, in which the MSDU frames are in a form of MSDU triplets, each MSDU triplet including a MSDU header, one of the MSDU frames, and a FCS for the MSDU frame.

7. The method of claim 1, further comprising:

transmitting the selected PSDU frames of the aggregate PSDU frames at different rates.

8. The method of claim 7, further comprising:

inserting an OFDM symbol between the selected PSDU frames having different rates.

9. The method of claim 1, further comprising:

acknowledging the single aggregate PSDU frame with a single acknowledgement message.

10. The method of claim 1, further comprising:

acknowledging the single aggregated PSDU frame with a BlockAck message.

11. The method of claim 1, further comprising:

acknowledging the single aggregated PSDU frame with a BlockAck message.

12. The method of claim 1, in which a size of the single aggregate MSDU is adapted according to an instantaneous condition of the channel.

13. The method of claim 1, in which a size of the single aggregate MSDU is adapted dynamically to a rate of transmission.

14. The method of claim 1, in which the plurality of MSDU frames are stored in a plurality of queues, and the aggregation of the MSDU frames is done on a per queue basis.

15. The method of claim 1, further comprising:

acknowledging the selected PSDU frames with the different destination addresses in a collision free manner.

16. The method of claim 1, further comprising:

aggregating the selected PSDU frames with the different destination addresses and the different traffic classes when the selected PSDU frames are subject to an internal collision in the transmitting station.

17. A system for aggregating frames to be transmitted over a channel in a wireless network, comprising:

a transmitter, the transmitter further comprising;

a media access control layer configured to receive a plurality of MSDU frames from a logical link layer of the transmitter;

means for aggregating selected MSDU frames having identical destination addresses and identical traffic classes into a single aggregate MPDU frame; and

a physical layer configured to receive, from the media access control layer in the transmitter, a plurality of the aggregate MPDU frames as PSDU frames in a physical layer, the physical layer further comprising;

means for aggregating selected PSDU frames with different destination addresses and different traffic classes into a single aggregate PPDU frame in the physical layer; and

means for transmitting the single aggregate PPDU frame on the channel of the wireless communications network.