Method and system for enabling HARQ operations on channels between stations in wireless communication networks

• US 7,630,355 B2
• Filed: 01/05/2007
• Issued: 12/08/2009
• Est. Priority Date: 01/05/2007
• 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: Zhang, Jinyun, Tao, Zhifeng, Teo, Koon Hoo, Uchida, Shigeru, Sawa, Kentarou, Kuze, Toshiyuki
• Primary Examiner(s): Patel; Jayanti K
• Assistant Examiner(s): CAMPBELL, MATTHEW T
• Application Number:
  US11/620,123
• Publication Number:
  US 20080165670A1
• Time in Patent Office: 1,068 Days
• Field of Search: None
• US Class Current: 370/343
• CPC Class Codes: H04L 1/1812 Hybrid protocols; Hybrid automatic repeat request [HARQ]
• CPC Class Codes: H04L 1/1822 involving configuration of automatic repeat request [ARQ] with parallel processes
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04L 47/34 ensuring sequence integrity, e.g. using sequence numbers
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals
• CPC Class Codes: H04L 5/0091 Signaling for the administration of the divided path
• CPC Class Codes: H04W 28/10 Flow control between communication endpoints
• CPC Class Codes: H04W 8/04 Registration at HLR or HSS [Home Subscriber Server]

Abstract

A method and system enables and improves performance of hybrid automatic repeat request (HARQ) operations on channels between stations of an orthogonal frequency division multiple access (OFDMA) wireless communication network. There, the number of parallel HARQ channels is increased adaptively, and one connection identifier is used to unambiguously identify a set of MAC protocol data units (MPDUs) communicated over parallel HARQ channels. A sequence number is used to avoid out-of-order MPDU delivery when MPDUs are transmitted over parallel HARQ channels. The MPDUs can be concatenated or encapsulated. The maximum number of the parallel HARQ channels can be increased to 256, and can be negotiated when a station enters or re-enters the network.

Claims

1. A method for enabling a hybrid automatic repeat request (HARQ) operation on channels between stations of an orthogonal frequency division multiple access (OFDMA) wireless communication network, comprising the steps of:

using a tunnel connection identifier to unambiguously identify a set of media access control (MAC) protocol data units (MPDUs) adapted to be communicated over parallel HARQ channels as part of a relay media access control protocol data unit (relay MPDU);

performing the HARQ operation using sequence numbers to avoid out-of-order delivery when the relay MPDU is transmitted over the parallel HARQ channels; and

adaptively increasing the number of parallel HARQ channels to improve performance of the HARQ operation, in which a maximum number of parallel HARQ channels is 256.

2. The method of claim 1, in which the MPDUs are concatenated.

3. The method of claim 2, in which the connection identifier is used in place of a RCID_IE field during the HARQ operation, if the HARQ operation is applied to the concatenation of MPDUs of different MAC connections.

4. The method of claim 1, in which the MPDUs are encapsulated.

5. The method of claim 1, in which an 8-bit long field specifies the maximum number of parallel HARQ channels.

6. The method of claim 1, further comprising:

negotiating the maximum number of the parallel HARQ channels used by a station when the station enters the network.

7. The method of claim 6, in which a subscriber basic capability request (SBC-REQ) and response (SBC-RSP) messages are used for the negotiating.

8. The method of claim 1, in which a maximum length of ACID field is a type-length-value used to indicate the maximum number of parallel HARQ channels allowed.

9. The method of claim 1, further comprising:

negotiating the maximum number of the parallel HARQ channels used by a station when the station re-enters the networks.

10. The method of claim 1, in which a logical connection in a mobile multihop relay network is a tunnel connection between a relay station and a base station.

11. The method of claim 10, in which the logic connection is established by HARQ layer, which is called a HARQ tunnel.

12. The method of claim 11, in which a MAC header is appended in front of a group of MPDUs to be concatenated in the HARQ tunnel.

13. The method of claim 1, in which a logical connection in a mobile multihop relay network is a tunnel connection on each relay link in the wireless communications network.

14. The method of claim 13, in which the corresponding form of connection identifier for the tunnel is used in the place of RCID during the HARQ operation, if the HARQ operation is applied on the concatenation of MPDUs of different MAC connections.

15. The method of claim 13, in which the corresponding form of connection identifier for the tunnel is used in the place of RCID during the HARQ operation, if the HARQ operation is applied on the encapsulation of MPDUs of different MAC connections.

16. The method of claim 15, in which the encapsulation of MPDUs of the different MAC connections refers to appending a new MAC header before the concatenation of MPDUs of the different MAC connections.

17. The method of claim 1, in which the sequence numbers have a short format of 8-bit long.

18. The method of claim 1, in which the sequence numbers are placed in the PDU sequence number (PDU SN) extended subheader of the MPDUs, which has a format of an extended subheader according to the IEEE 802.16e-2005 standard.

19. The method of claim 18, in which the PDU SN extended subheader is placed between a MAC header appended by tunneling and the MPDUs, if encapsulation of MPDUs is used in the tunneling.

20. The method of claim 18, in which the PDU SN extended subheader is placed between a MAC header of each individual MPDU and a MAC service data unit (SDU) of each individual MPDU, if no encapsulation is made in the tunneling.

21. The method of claim 18, in which the PDU SN extended subheader is placed between a MAC header appended by HARQ layer tunneling and the following MPDUs, if HARQ tunneling is used.

22. The method of claim 1, in which the sequence numbers have a long format of 16-bit long.

23. A system for enabling hybrid automatic repeat request (HARQ) operations on channels between stations of an orthogonal frequency division multiple access (OFDMA) wireless communication network, comprising:

means for using a tunnel connection identifier to unambiguously identify a set of MAC protocol data units (MPDUs) adapted to be communicated over parallel HARQ channels as part of a relay MPDU;

means for performing the HARQ operation using sequence number to avoid out-of-order MPDU delivery when the relay MPDU is transmitted over the parallel HARQ channels; and

means for adaptively increasing the number of parallel HARQ channels to improve performance of the HARQ operation, in which a maximum number of parallel HARQ channels is 256.