Method and apparatus for configuring search space of a downlink control channel

• US 9,820,270 B2
• Filed: 09/18/2015
• Issued: 11/14/2017
• Est. Priority Date: 03/19/2012
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Li, Yingyang, Sun, Chengjun
• Primary Examiner(s): Gidado, Rasheed
• Application Number:
  US14/858,613
• Publication Number:
  US 20160014731A1
• Time in Patent Office: 788 Days
• CPC Class Codes: H04L 1/0045 Arrangements at the receiver end
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals
• CPC Class Codes: H04L 5/0064 Rate requirement of the data, e.g. scalable bandwidth, data priority
• CPC Class Codes: H04W 72/0446 Resources in time domain, e.g. slots or frames
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal

Abstract

A method for configuring a search space of a downlink control channel is provided. The method includes determining the parameters for Enhanced Physical Downlink Control Channel (E-PDCCH) candidates of each aggregate level according to the number of Resource Elements (RE) in a subframe and/or the number of bits of Downlink Control Information (DCI) formats, when the parameters for E-PDCCH candidates of E-PDCCH search space is configured, determining, by a User Equipment (UE), the parameters for E-PDCCH candidates according to a current downlink subframe and a detected DCI format, and detecting blindly, by the UE, the E-PDCCH candidates in the E-PDCCH search space corresponding to the parameters for E-PDCCH candidates. The present invention also provides a UE and a base station. Application of the present invention can improve the flexibility of the base station scheduling, and reduce the possibility that the E-PDCCHs of different UEs block each other.

Claims

1. A method by a terminal in a wireless communication system, the method comprising:

identifying a downlink control information (DCI) format for an enhanced physical downlink control channel (E-PDCCH);

identifying a quantity of E-PDCCH candidates of each of aggregation levels based on whether the identified DCI format is included in a predefined group of DCI format; and

receiving downlink control information by monitoring the E-PDCCH candidates in an E-PDCCH search space,

wherein the E-PDCCH search space is determined based on the identified quantity of E-PDCCH candidates.

2. The method of claim 1, wherein the quantity of E-PDCCH candidates is identified based on the identified DCI format and a quantity of resource elements (REs) in a physical resource block (PRB) pair for the E-PDCCH.

3. The method of claim 1, further comprising:

identifying whether the DCI format is included in a first group of DCI format or a second group of DCI format,

wherein a number of bits of control information associated with the first group of DCI format is more than a number of bits of control information associated with the second group of DCI format.

4. The method of claim 1, wherein a number of bits of control information associated with each of DCI formats is different from each other.

5. The method of claim 2, wherein the quantity of REs in the PRB pair is calculated based on a quantity of REs for a common reference signal (CRS) and a channel state information reference signal (CSI-RS) in the PRB pair configured for the E-PDCCH.

6. The method of claim 1, further comprising:

receiving information indicating whether the terminal monitors the E-PDCCH via a higher layer signaling.

7. The method of claim 2, wherein the quantity of E-PDCCH candidates is identified based on a downlink subframe type, the quantity of REs, and the DCI format.

8. A terminal in a wireless communication system, the terminal comprising:

a transceiver configured to transmit and receive a signal; and

a controller configured to;

identify a downlink control information (DCI) format for an enhanced physical downlink control channel (E-PDCCH),

identify a quantity of E-PDCCH candidates of each of aggregation levels based on whether the identified DCI format is included in a predefined group of DCI format, and

receive downlink control information by monitoring the E-PDCCH candidates in an E-PDCCH search space,

wherein the E-PDCCH search space is determined based on the identified quantity of E-PDCCH candidates.

9. The terminal of claim 8, wherein the quantity of E-PDCCH candidates is identified based on the identified DCI format and a quantity of resource elements (REs) in a physical resource block (PRB) pair for the E-PDCCH.

10. The terminal of claim 8,

wherein the controller is further configured to identify whether the DCI format is included in a first group of DCI format or a second group of DCI format, and

wherein a number of bits of control information associated with the first group of DCI format is more than a number of bits of control information associated with the second group of DCI format.

11. The terminal of claim 8, wherein a number of bits of control information associated with each of DCI formats is different from each other.

12. The terminal of claim 9, wherein the quantity of REs in the PRB pair is calculated based on a quantity of REs for a common reference signal (CRS) and a channel state information reference signal (CSI-RS) in the PRB pair configured for the E-PDCCH.

13. The terminal of claim 8, wherein the controller is further configured to receive information indicating whether the terminal monitors the E-PDCCH via a higher layer signaling.

14. The terminal of claim 9, wherein the quantity of E-PDCCH candidates is identified based on a downlink subframe type, the quantity of REs, and the DCI format.

15. A method by a base station in a wireless communication system, the method comprising:

identifying a downlink control information (DCI) format for an enhanced physical downlink control channel (E-PDCCH);

identifying a quantity of E-PDCCH candidates of each of aggregation levels based on whether the identified DCI format is included in a predefined group of DCI format;

selecting the E-PDCCH candidate in an E-PDCCH search space that is determined based on the quantity of E-PDCCH candidates; and

transmitting the E-PDCCH using resources corresponding to the selected E-PDCCH candidate.

16. The method of claim 15, wherein the quantity of E-PDCCH candidates is identified based on the identified DCI format and a quantity of resource elements (REs) in a physical resource block (PRB) pair for the E-PDCCH.

17. The method of claim 15, further comprising:

identifying whether the DCI format is included in a first group of DCI format or a second group of DCI format,

wherein a number of bits of control information associated with the first group of DCI format is more than a number of bits of control information associated with the second group of DCI format.

18. The method of claim 15, wherein a number of bits of control information associated with each of DCI formats is different from each other.

19. The method of claim 16, wherein the quantity of REs in the PRB pair is calculated based on a quantity of REs for a common reference signal (CRS) and a channel state information reference signal (CSI-RS) in the PRB pair configured for the E-PDCCH.

20. The method of claim 15, further comprising:

transmitting information indicating whether the terminal monitors the E-PDCCH via a higher layer signaling.

21. The method of claim 16, wherein the quantity of E-PDCCH candidates is identified based on a downlink subframe type, the quantity of REs, and the DCI format.

22. A base station in a wireless communication system, the base station comprising:

a controller configured to transmit and receive a signal; and

a controller configured to;

identify a downlink control information (DCI) format for an enhanced physical downlink control channel (E-PDCCH),

identify a quantity of E-PDCCH candidates of each of aggregation levels based on whether the identified DCI format is included in a predefined group of DCI format,

select the E-PDCCH candidate in an E-PDCCH search space that is determined based on the quantity of E-PDCCH candidates, and

transmit the E-PDCCH using resources corresponding to the selected E-PDCCH candidate.

23. The base station of claim 22, wherein the quantity of E-PDCCH candidates is identified based on the identified DCI format and a quantity of resource elements (REs) in a physical resource block (PRB) pair for the E-PDCCH.

24. The base station of claim 22,

wherein the controller is further configured to identify whether the DCI format is included in a first group of DCI format or a second group of DCI format, and

wherein a number of bits of control information associated with the first group of DCI format is more than a number of bits of control information associated with the second group of DCI format.

25. The base station of claim 22, wherein a number of bits of control information associated with each of DCI formats is different from each other.

26. The base station of claim 23, wherein the quantity of REs in the PRB pair is calculated based on a quantity of REs for a common reference signal (CRS) and a channel state information reference signal (CSI-RS) in the PRB pair configured for the E-PDCCH.

27. The base station of claim 22, wherein the controller is further configured to transmit information indicating whether the terminal monitors the E-PDCCH via a higher layer signaling.

28. The base station of claim 23, wherein the quantity of E-PDCCH candidates is identified based on a downlink subframe type, the quantity of REs, and the DCI format.