METHOD AND APPARATUS FOR CONTROL CHANNEL DECODING IN MULTI-NODE SYSTEM

• US 20140286285A1
• Filed: 10/23/2012
• Published: 09/25/2014
• Est. Priority Date: 10/23/2011
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Park, Sung Ho, Chun, Jin Young, Kim, Ki Tae, Kim, Su Nam, Kang, Ji Won, Ihm, Bin Chul
• Granted Patent: US 9,781,704 B2
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04L 1/0025 Transmission of mode-switching indication
• CPC Class Codes: H04L 1/0038 Blind format detection for detection of modulation format H04L27/0012
• CPC Class Codes: H04L 27/0008 arrangements for allowing a transmitter or receiver to use more than one type of modulation negotiating modulation type for two-way transmission paths H04L5/1453
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals
• CPC Class Codes: H04W 72/20 Control channels or signalling for resource management

Abstract

Provided are a method and an apparatus for control channel decoding of a terminal in a multi-node system. The method sets a search space for searching a control channel and can perform the decoding by using different demodulation methods according to aggregation levels capable of constituting the control channel within the search space. In addition, the method determines the DCI format to be searched according to a transmission mode and can use different demodulation methods according to the determined DCI format. Furthermore, the method modulates DCI format to a first modulation degree when demodulating the DCI format, and can demodulate the DCI format to a second modulation degree when the DCI format is not detected.

Claims

1. A method of decoding a control channel of a user equipment (UE) in a multi-node system, the method comprising:

configuring a search space for searching for a control channel, the search space being included within a data region from among a control region including initial N (N is an integer which is one of 0 to

     4) orthogonal frequency division multiplexing (OFDM) symbols and a data region including remaining OFDM symbols in a subframe including a plurality of OFDM symbols;

attempting decoding using a first aggregation level, from among aggregation levels which can form the control channel within the search space, as a unit; and

attempting decoding using a second aggregation level, from among the aggregation levels within the search space, as a unit,

wherein when the decoding using the first aggregation level as the unit is attemped, a first demodulation scheme is used, and

when the decoding using the second aggregation level as the unit is attempted, a second demodulation scheme is used.

2. The method of claim 1, wherein the control channel is an enhanced physical downlink control channel (E-PDCCH).

3. The method of claim 1, wherein the first aggregation level indicates that the control channel is composed of one or two resource blocks, and the second aggregation level indicates that the control channel is compose of 4 or 8 resource blocks

4. The method of claim 1, wherein a control channel composed of the first aggregation level is demodulated by 16 quadrature amplitude modulation (16QAM), and a control channel composed of the second aggregation level is demodulated by quadrature phase shift keying (QPSK).

5. The method of claim 1, wherein the first demodulation scheme uses 16QAM, and the second demodulation scheme uses QPSK.

6. A method of decoding a control channel of a user equipment (UE) in a multi-node system, the method comprising:

receiving mode information which reveals a downlink transmission mode and an uplink transmission mode;

determining a plurality of downlink control information (DCI) formats to be searched according to the mode information;

demodulating DCI formats belonging to a first DCI format set, from among the plurality of DCI formats, in a first demodulation scheme; and

demodulating DCI formats belonging to a second DCI format set, from among the plurality of DCI formats, in a second demodulation scheme.

7. The method of claim 6, wherein the first demodulation scheme uses 16 quadrature amplitude modulation (16QAM), and the second demodulation scheme uses quadrature phase shift keying (QPSK).

8. The method of claim 6, wherein the first DCI format set includes DCI formats whose payload size is equal to or smaller than a payload size of a specific DCI format from among the plurality of DCI formats, and the second DCI format set includes DCI formats whose payload size is greater than the payload size of the specific DCI format.

9. The method of claim 6, wherein the plurality of DCI formats are modulated with 16QAM or QPSK.

10. The method of claim 9, wherein a DCI format, which is modulated with 16QAM, from among the plurality of DCI formats, is a combination of two DCI formats modulated with QPSK.

11. The method of claim 10, wherein the DCI format modulated with the 16QAM includes an indicator indicating whether two DCI formats modulated with the QPSK include both downlink scheduling information and uplink scheduling information or only one of the downlink scheduling information and the uplink scheduling information.

12. A user equipment (UE) for decoding a control channel in a multi-node system, the UE comprising:

a radio frequency (RF) unit which transmits and receives a wireless signal; and

a processor connected to the RF unit,

wherein the processor is configured for;

configuring a search space for searching for a control channel, the search space being included within a data region from among a control region including initial N (N is an integer which is one of 0 to

     4) orthogonal frequency division multiplexing (OFDM) symbols and a data region including remaining OFDM symbols in a subframe including a plurality of OFDM symbols;

attempting decoding using a first aggregation level, from among aggregation levels which can form the control channel within the search space, as a unit; and

attempting decoding using a second aggregation level, from among the aggregation levels within the search space, as a unit,

wherein when the decoding using the first aggregation level as the unit is attemped, a first demodulation scheme is used, and

when the decoding using the second aggregation level as the unit is attempted, a second demodulation scheme is used.

13. The UE of claim 12, wherein the first demodulation scheme uses 16 quadrature amplitude modulation (16QAM), and the second demodulation scheme uses quadrature phase shift keying (QPSK).

14. A user equipment (UE) for decoding a control channel in a multi-node system, the UE comprising:

a radio frequency (RF) unit which transmits and receives a wireless signal; and

a processor connected to the RF unit,

wherein the processor is configured for;

receiving mode information which reveals a downlink transmission mode and an uplink transmission mode;

determining a plurality of downlink control information (DCI) formats to be searched according to the mode information;

demodulating DCI formats belonging to a first DCI format set, from among the plurality of DCI formats, in a first demodulation scheme; and

demodulating DCI formats belonging to a second DCI format set, from among the plurality of DCI formats, in a second demodulation scheme.

15. The UE of claim 14, wherein the plurality of DCI formats are demodulated with 16QAM or QPSK.