Downlink Transmissions for Type 2 Relay

• US 20100325506A1
• Filed: 06/16/2010
• Published: 12/23/2010
• Est. Priority Date: 06/19/2009
• Status: Active Grant

• Current Assignee: Malikie Innovations Limited (Key Patent Innovations Limited)
• Original Assignee: Blackberry Limited
• Inventors: Vrzic, Sophie, Bontu, Chandra S., Womack, James Earl, Song, Yi, Yu, Yi, Earnshaw, Andrew Mark, Fong, Mo-Han, Cai, Zhijun
• Granted Patent: US 8,468,412 B2
• Time in Patent Office: Days
• US Class Current: 714/748
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal
• CPC Class Codes: H04W 84/047 using dedicated repeater stations

Abstract

A method for transmitting data to a user agent. The method includes a relay node receiving information from an access node, the information containing the data that is to be transmitted to the user agent and control information that the access node will use to transmit the data to the user agent. The method further includes the relay node transmitting the data to the user agent at the time the access node transmits the data to the user agent, the relay node using the control information that the access node uses to transmit the data to the user agent.

Claims

1. A method for transmitting data to a user agent, comprising:

a relay node receiving information from an access node, the information containing the data that is to be transmitted to the user agent and control information that the access node will use to transmit the data to the user agent; and

the relay node transmitting the data to the user agent at the time the access node transmits the data to the user agent, the relay node using the control information that the access node uses to transmit the data to the user agent.

2. The method of claim 1, wherein the data is at least one of:

physical downlink control channel (PDCCH) content information;

a medium access control (MAC) protocol data unit (PDU); and

a physical layer (PHY) transport block.

3. The method of claim 1, wherein the control information is at least one of:

modulation and coding information;

resource allocation information;

scheduling information;

a number of orthogonal frequency division multiplexing symbols;

an aggregation level;

a subframe index for the transmission to the user agent;

a location of corresponding downlink control information (DCI) on the PDCCH; and

the identity of the user agent.

4. The method of claim 1, wherein, when the user agent is unable to successfully decode the data, the user agent sends a negative acknowledgement (NACK) message to the access node and the relay node.

5. The method of claim 4, wherein, when the access node and the relay node receive the NACK and when dynamic scheduling is used, the access node determines the parameters that are to be used for a retransmission of the data and a time of the retransmission, the access node notifies the relay node of the parameters and the time, and the access node and the relay node retransmit the data at the time determined by the access node using the parameters specified by the access node.

6. The method of claim 4, wherein, when the access node and the relay node receive the NACK and when non-adaptive synchronous scheduling is used, the access node and the relay node retransmit the data at the same time using the same control information that was used in the previous transmission of the data.

7. The method of claim 6, wherein the access node provides the user agent with the control information over the PDCCH that will be used for the retransmission, and wherein the control information used for the retransmission is the same as the control information used for the original transmission.

8. The method of claim 7, wherein the access node informs the relay node to use the same control information that was used in the previous transmission of the data for the retransmission.

9. The method of claim 1, wherein the access node transmits the control information in the medium access control (MAC) layer.

10. The method of claim 9, wherein the control information that is transmitted from the access node to the relay node in the MAC layer includes at least one of:

an N_OFDM field;

a C-RNTI field;

a length field;

a PDCCH (PDCCH-UE-i) field;

a PDCCH (C-RNTI-UE-i) field; and

a DATA-UE-i field.

11. The method of claim 9, wherein the control information that is transmitted in the MAC layer includes a field specifying a transmission mode to be used between the access node and the relay node.

12. An access node in a wireless telecommunications system, comprising:

a component configured such that the access node transmits information containing data that is to be transmitted to a user agent by a relay node and control information, wherein the control information useable by the relay node to coordinate transmission of the data to the user agent with the access node transmission of the data to the user agent.

13. The access node of claim 12, wherein the data is at least one of:

physical downlink control channel (PDCCH) content information;

a medium access control (MAC) protocol data unit (PDU); and

a physical layer (PHY) transport block.

14. The access node of claim 12, wherein the control information is at least one of:

modulation and coding information;

resource allocation information;

scheduling information;

a number of orthogonal frequency division multiplexing symbols;

an aggregation level;

a subframe index for the transmission to the user agent;

a location of corresponding downlink control information (DCI) on the PDCCH; and

the identity of the user agent.

15. The access node of claim 12, wherein, when the user agent is unable to successfully decode the data, the user agent sends a negative acknowledgement (NACK) message to the access node and the relay node.

16. The access node of claim 15, wherein, when the access node and the relay node receive the NACK and when dynamic scheduling is used, the access node determines the parameters that are to be used for a retransmission of the data and a time of the retransmission, the access node notifies the relay node of the parameters and the time, and the access node and the relay node retransmit the data at the time determined by the access node using the parameters specified by the access node.

17. The access node of claim 15, wherein, when the access node and the relay node receive the NACK and when non-adaptive synchronous scheduling is used, the access node and the relay node retransmit the data at the same time using the same control information that was used in the previous transmission of the data.

18. The access node of claim 17, wherein the access node provides the user agent with the control information over the PDCCH that will be used for the retransmission, and wherein the control information used for the retransmission is the same as the control information used for the original transmission.

19. The access node of claim 18, wherein the access node informs the relay node to use the same control information that was used in the previous transmission of the data for the retransmission.

20. The access node of claim 12, wherein the access node transmits the control information in the medium access control (MAC) layer.

21. The access node of claim 20, wherein the control information that is transmitted from the access node to the relay node in the MAC layer includes at least one of:

an N_OFDM field;

a C-RNTI field;

a length field;

a PDCCH (PDCCH-UE-i) field;

a PDCCH (C-RNTI-UE-i) field; and

a DATA-UE-i field.

22. The access node of claim 20, wherein the control information that is transmitted in the MAC layer includes a field specifying a transmission mode to be used between the access node and the relay node.

23. A relay node in a wireless telecommunications system, comprising:

a component configured such that the relay node receives information containing data that is to be transmitted to a user agent and control information, wherein the relay node uses the control information to coordinate transmission of the data to the user agent with an access node transmission of the data to the user agent.

24. The relay node of claim 23, wherein the data is at least one of:

physical downlink control channel (PDCCH) content information;

a medium access control (MAC) protocol data unit (PDU); and

a physical layer (PHY) transport block.

25. The relay node of claim 23, wherein the control information is at least one of:

modulation and coding information;

resource allocation information;

scheduling information;

a number of orthogonal frequency division multiplexing symbols;

an aggregation level;

a subframe index for the transmission to the user agent;

a location of corresponding downlink control information (DCI) on the PDCCH; and

the identity of the user agent.

26. The relay node of claim 23, wherein, when the user agent is unable to successfully decode the data, the user agent sends a negative acknowledgement (NACK) message to the access node and the relay node.

27. The relay node of claim 26, wherein, when the access node and the relay node receive the NACK and when dynamic scheduling is used, the access node determines the parameters that are to be used for a retransmission of the data and a time of the retransmission, the access node notifies the relay node of the parameters and the time, and the access node and the relay node retransmit the data at the time determined by the access node using the parameters specified by the access node.

28. The relay node of claim 26, wherein, when the access node and the relay node receive the NACK and when non-adaptive synchronous scheduling is used, the access node and the relay node retransmit the data at the same time using the same control information that was used in the previous transmission of the data.

29. The relay node of claim 28, wherein the access node provides the user agent with the control information over the PDCCH that will be used for the retransmission, and wherein the control information used for the retransmission is the same as the control information used for the original transmission.

30. The relay node of claim 29, wherein the access node informs the relay node to use the same control information that was used in the previous transmission of the data for the retransmission.

31. The relay node of claim 23, wherein the relay node receives the control information in the medium access control (MAC) layer.

32. The relay node of claim 31, wherein the control information that is transmitted from the access node to the relay node in the MAC layer includes at least one of:

an N_OFDM field;

a C-RNTI field;

a length field;

a PDCCH (PDCCH-UE-i) field;

a PDCCH (C-RNTI-UE-i) field; and

a DATA-UE-i field.

33. The relay node of claim 31, wherein the control information that is transmitted in the MAC layer includes a field specifying a transmission mode to be used between the access node and the relay node.

34. A method for scheduling data to and/or from a user agent, comprising:

an access node separating relay-assisted and non-relay-assisted user agents into different groups; and

the access node performing scheduling for the two groups separately.

35. The method of claim 34, wherein the relay-assisted group of user agents is scheduled further in advance of the corresponding time for transmission to the user agent than is the non-relay-assisted group of user agents.

36. The method of claim 35, wherein the advance scheduling allows time for communication of the corresponding relay-assisted scheduling information to one or more relay nodes.

37. The method of claim 34, wherein relay-assisted user agents are only scheduled into relay-assisted subframes, but non-relay-assisted user agents may be scheduled into either non-relay-assisted or relay-assisted subframes.

38. The method of claim 37, wherein relay-assisted subframes are dynamically reserved by the access node.

39. The method of claim 37, wherein relay-assisted subframes occur according to a pre-determined pattern.

40. An access node in a wireless telecommunications system, comprising:

a component configured such that the access node transmits control information useable by a relay node to coordinate relay node transmission of data to a user agent with access node transmission of the data to the user agent, wherein the access node uses a boosted channel quality indicator value for scheduling.

41. The access node of claim 40, wherein the amount of boosting depends on the link quality between relay node and the user agent.

42. The access node of claim 40, wherein the access node estimates the amount of boosting based on the long-term channel condition between the relay node and the user agent.

43. The access node of claim 40, wherein the access node adjusts the amount of boosting based on a target packet error rate.