Method for resource element group downsizing of R-PDCCH and mobile telecommunication system for the same
The present invention relates to a method for reducing a resource element group (REG) size, which is used at a control channel element (CCE) for a relay physical downlink control channel (R-PDCCH), for the purpose of easy interleaving by a physical resource block (PRB) unit for the R-PDCCH, and a mobile telecommunication system for the same. The mobile telecommunication system of the present invention includes reducing the CCE size to 8 REGs or less of the R-PDCCH to be included in a single PRB.
1. A method for reducing a resource element group (REG) size of a relay physical downlink control channel (R-PDCCH) comprising:
reducing a control channel element (CCE) size of the R-PDCCH to be included in a single physical resource block (PRB); and
downsizing a size of resource allocation bits included in a downlink control information (DCI) to downsize the CCE size.
2. The method of claim 1 , wherein the CCE size is reduced to 8 REGs or less.
3. The method of claim 2 , wherein the R-PDCCH uses a demodulation reference signal (DMRS) or a cell specific reference signal (CRS).
4. The method of claim 1 , wherein the resource allocation bits is determined to a smallest integer greater than a result from dividing a system bandwidth by a resource block group (RBG) size.
5. The method of claim 4 , wherein the RBG size is twice the RBG size for a user equipment (UE) according to the system bandwidth.
6. The method of claim 1 , wherein the resource allocation bits is calculated by equation (1),
(N RB DL /P)−(log 2 (P))−1(bits) (1)
wherein results of N RB DL /P and log, (P) are determined to the smallest integers, which are equal to or greater than the results thereof, respectively.
7. A mobile telecommunication system comprising:
reducing a control channel element (CCE) size of a relay physical downlink control channel (R-PDCCH) to 8 resource element groups (REGs) or less to be included in a physical resource block (PRB), and
reducing a size of resource allocation bits included in a downlink control info nation (DCI) for reducing of the CCE size.
8. The mobile telecommunication system of claim 7 ,
wherein the resource allocation bits is determined to a smallest integer greater than an amount resulting from dividing a system bandwidth by a resource block group (RBG).
9. The mobile telecommunication system of claim 8 , wherein the RBG size is twice than the RBG size for a user equipment (UE) according to the system bandwidth.
10. The mobile telecommunication system of claim 8 , wherein the R-PDCCH uses a demodulation reference signal (DMRS) or a cell specific reference signal (CRS).