Method and apparatus for transceiving downlink control information in a wireless access system

• US 9,660,782 B2
• Filed: 10/19/2012
• Issued: 05/23/2017
• Est. Priority Date: 10/19/2011
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Jang, Jiwoong, Cho, Hangyu
• Primary Examiner(s): Morlan, Robert M
• Assistant Examiner(s): Mansoury, Nourali
• Application Number:
  US14/351,120
• Publication Number:
  US 20140286281A1
• Time in Patent Office: 1,677 Days
• CPC Class Codes: H04L 5/0023 Time-frequency-space
• CPC Class Codes: H04L 5/0028 Variable division signaling therefor H04L5/0092
• CPC Class Codes: H04L 5/005 of common pilots, i.e. pilots destined for multiple users or terminals
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals
• CPC Class Codes: H04L 5/0092 Indication of how the channel is divided
• CPC Class Codes: H04W 48/02 Access restriction performed under specific conditions

Abstract

The present invention relates to a method and an apparatus for transceiving downlink control information (DCI) in a wireless access system. More particularly, the method comprises: a step of mapping a physical downlink control channel (PDCCH) to a common search space (CSS) defined within a physical downlink shared channel (PDSCH) region in a frequency first mapping manner; and a step of transmitting DCI to a terminal through the mapped PDCCH.

Claims

1. A method for transmitting DCI (Downlink Control Information) in a machine type communication (MTC) system, the method comprising:

mapping a PDCCH (Physical Downlink Control Channel) to a CSS (Common Search Space) in a descending order on a frequency axis by using a frequency first mapping method, wherein the CSS is defined in a first slot of a PDSCH (Physical Downlink Shared Channel) region; and

transmitting the DCI to a user equipment through the mapped PDCCH,

wherein the PDCCH is mapped in a descending order on a time axis starting from a last symbol of the first slot, and

wherein a CRC (Cyclic Redundancy Check) of the PDCCH is added at an end of the PDCCH to indicate a last symbol of the CSS.

2. The method of claim 1, wherein the CSS is defined in last 4 symbols of the first slot or in a symbol located after a legacy PDCCH (legacy Physical Downlink Control Channel) region up to the last symbol of the first slot.

3. The method of claim 1, wherein the DCI is transmitted based upon a CRS (Common Reference Signal) or a DMRS (Demodulation Reference Signal).

4. The method of claim 1, wherein the PDCCH is mapped in CCE (Control Channel Element) units or RB (Resource Block) units.

5. The method of claim 1, wherein the DCI includes information on uplink data transmission duration.

6. The method of claim 1, wherein the DCI simultaneously designates multiple PDSCH resources or multiple PUSCH (Physical Uplink Shared Channel) resources.

7. The method of claim 1, wherein the DCI is CRC (Cyclic Redundancy Check) masked by using a group identifier, wherein the group identifier is allocated to a user equipment group including multiple groups.

8. A method for receiving DCI (Downlink Control Information) in a machine type communication (MTC), the method comprising:

receiving the DCI through a PDCCH (Physical Downlink Control Channel),

wherein the PDCCH is mapped to a CSS (Common Search Space) in a descending order on a frequency axis by using a frequency first mapping method, wherein the CSS is defined in a first slot of a PDSCH (Physical Downlink Shared Channel) region,

wherein the PDCCH is mapped in a descending order on a time axis starting from a last symbol of the first slot, and

wherein a CRC (Cyclic Redundancy Check) of the PDCCH is added at an end of the PDCCH to indicate a last symbol of the CSS.

9. The method of claim 8, wherein the CSS is defined in last 4 symbols of the first slot or in a symbol located after a legacy PDCCH (legacy Physical Downlink Control Channel) region up to the last symbol of the first slot.

10. The method of claim 8, wherein the DCI is transmitted based upon a CRS (Common Reference Signal) or a DMRS (Demodulation Reference Signal).

11. The method of claim 8, wherein the PDCCH is mapped in CCE (Control Channel Element) units or RB (Resource Block) units.

12. The method of claim 8, wherein the DCI includes information on uplink data transmission duration.

13. The method of claim 8, wherein the DCI simultaneously designates multiple PDSCH resources or multiple PUSCH (Physical Uplink Shared Channel) resources.

14. The method of claim 8, wherein the DCI is CRC (Cyclic Redundancy Check) masked by using a group identifier, wherein the group identifier is allocated to a user equipment group including multiple groups.

15. A base station configured to transmit DCI (Downlink Control Information) in a machine type communication (MTC), the base station comprising:

an RF (Radio Frequency) unit configured to transceiver radio signals; and

a processor configured to map a PDCCH (Physical Downlink Control Channel) to a CSS (Common Search Space) in a descending order on a frequency axis by using a frequency first mapping method, wherein the CSS is defined in a first slot of a PDSCH (Physical Downlink Shared Channel) region, and to transmit the DCI to a user equipment through the mapped PDCCH,

wherein the PDCCH is mapped in a descending order on a time axis starting from a last symbol of the first slot, and

wherein a CRC (Cyclic Redundancy Check) of the PDCCH is added at an end of the PDCCH to indicate a last symbol of the CSS.

16. A user equipment configured to receive DCI (Downlink Control Information) in a machine type communication, the user equipment comprising:

an RF (Radio Frequency) unit configured to transceiver radio signals; and

a processor configured to receive the DCI through a PDCCH (Physical Downlink Control Channel),

wherein the PDCCH is mapped to a CSS (Common Search Space) in a descending order on a frequency axis by using a frequency first mapping method, wherein the CSS is defined in a first slot of a PDSCH (Physical Downlink Shared Channel) region,

wherein the PDCCH is mapped in a descending order on a time axis starting from a last symbol of the first slot, and

wherein a CRC (Cyclic Redundancy Check) of the PDCCH is added at an end of the PDCCH to indicate a last symbol of the CSS.