Method and device for monitoring downlink control channel

• US 9,730,202 B2
• Filed: 11/14/2013
• Issued: 08/08/2017
• Est. Priority Date: 11/14/2012
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Seo, Hanbyul, Kim, Hakseong, Kim, Byounghoon
• Primary Examiner(s): Moore, Ian N
• Assistant Examiner(s): La, Phong
• Application Number:
  US14/442,463
• Publication Number:
  US 20160255609A1
• Time in Patent Office: 1,363 Days
• CPC Class Codes: H04B 7/0413 MIMO systems
• CPC Class Codes: H04B 7/0608 Antenna selection according to transmission parameters
• CPC Class Codes: H04J 11/00 Orthogonal multiplex systems, e.g. using WALSH codesH04J13/00 takes precedence
• CPC Class Codes: H04J 13/16 Code allocation
• CPC Class Codes: H04L 2012/5673 Coding or scrambling
• CPC Class Codes: H04L 25/03866 using scrambling
• CPC Class Codes: H04L 5/00 Arrangements affording multiple use of the transmission path
• 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 48/16 Discovering, processing access restriction or access information
• CPC Class Codes: H04W 72/20 Control channels or signalling for resource management
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal

Abstract

A method for monitoring a control channel in a wireless communication system and a wireless device using the same are provided. The wireless device monitors a downlink control channel in at least one physical resource block (PRB) pair of a subframe that is assigned for an enhanced physical downlink control channel (EPDCCH) set. A beatstream for downlink control information of the downlink control channel is scrambled by a scrambling sequence that is initialized on the basis of a scrambling initialization value allocated to the EPDCCH set.

Claims

1. A method for monitoring a control channel in a wireless communication system, the method comprising:

receiving, by the wireless device, configuration information to configure an enhanced physical downlink control channel (EPDCCH) set from a base station, the configuration information including a resource assignment indicating at least one physical resource block-pair and scrambling initialization information indicating a scrambling initialization value,

wherein the configuration information further includes an identifier of the EPDCCH set;

monitoring, by a wireless device, a downlink control channel in the EPDCCH set;

generating, by the wireless device, a scrambling sequence; and

descrambling, by the wireless device, a bit stream for downlink control information on the downlink control channel with the scrambling sequence,

wherein the generation of the scrambling sequence is initialized with C_init=(floor(ns/2))2⁹+n_i, where ns denotes a slot number within a radio frame, floor (x) denotes a largest integer not greater than x, and n_i denotes the scrambling initialization value assigned for the EPDCCH set.

2. The method of claim 1, wherein the scrambling sequence is obtained from a pseudo-random sequence.

3. The method of claim 2, wherein the pseudo-random sequence is defined by:

c(n)=(x₁(n+Nc)+x₂(n+Nc))mod 2

x₁(n+31)=(x₁(n+3)+x₁(n))mod 2

x₂(n+31)=(x₂(n+3)+x₂(n+2)+x₂(n+1)+x₂(n))mod 2

where Nc=1600, n=0, . . . , N−

1, and N denotes a length of the pseudo-random sequence.

4. The method of claim 1, wherein the bit stream b(i) for the downlink control information on the downlink control channel is scrambled with the scrambling sequence c(i) according to (b(i)+c(i) mod 2.

5. The method of claim 1, wherein the step of monitoring the downlink control channel includes:

demodulating the downlink control information on the downlink control channel to obtain the bit stream for the downlink control information.

6. The method of claim 1, wherein the bit stream for the downlink control information has a cyclic redundancy check (CRC) that is scrambled with an identifier of the wireless device.

7. The method of claim 1, wherein the scrambling initialization value indicated by n_i is different from a physical cell identity.

8. The method of claim 1, wherein the scrambling initialization value is received per the EPDCCH set.

9. A device configured to monitor a control channel in a wireless communication system, the device comprising:

a processor; and

a radio frequency (RF) unit configured to receive configuration information to configure an enhanced physical downlink control channel (EPDCCH) set from a base station, the configuration information including a resource assignment indicating at least one physical resource block-pair and scrambling initialization information indicating a scrambling initialization value,

wherein the configuration information further includes an identifier of the EPDCCH set; and

a memory operatively coupled with the processor and storing instructions that, when executed by the processor, cause the device to monitor a downlink control channel in the EPDCCH set,

wherein the processor is configured to generate a scrambling sequence and descramble a bit stream for downlink control information on the downlink control channel with the scrambling sequence, and

wherein the processor initializes the generation of the scrambling sequence with c_init=(floor (ns/2))2⁹+n_i, where ns denotes a slot number within a radio frame, floor (x) denotes a largest integer not greater than x, and n_i denotes a the scrambling initialization value assigned for the EPDCCH set.

10. The device of claim 9, wherein the scrambling sequence is obtained from a pseudo-random sequence.

11. A method for transmitting downlink control information in a wireless communication system, performed by a base station, the method comprising:

transmitting configuration information to configure an enhanced physical downlink control channel (EPDCCH) set to a user equipment, the configuration information including a resource assignment indicating at least one physical resource block-pair and scrambling initialization information indicating a scrambling initialization value,

wherein the configuration information further includes an identifier of the EPDCCH set;

generating a bit stream for the downlink control information;

generating a scrambling sequence;

scrambling the bit stream for the downlink control information with the scrambling sequence; and

transmitting the scrambled bit stream in the EPDCHH set,

wherein the generation of the scrambling sequence is initialized with c_init=(floor(ns/2))2⁹+n_i, where ns denotes a slot number within a radio frame, floor (x) denotes a largest integer not greater than x, and n_i denotes the scrambling initialization value assigned for the EPDCCH set.

12. The method of claim 11, wherein the scrambling sequence is generated from a pseudo-random sequence.