Method and arrangement in a communication system

Abstract

The present invention relates to a method and an arrangement of efficiently utilizing radio resources in a communication network, comprising a communication network node transmitting information on shared control channels (SCCH) to one or more user equipments. The information is transmitted over either a narrow or a wide bandwidth depending on which mode said one or more user equipments are, either a power saving mode or an active mode.

1 . A method for efficiently utilizing radio resources in a communication network comprising a communication network node transmitting information on control channels to one or more user equipments, wherein
 defining a subset of Transmission Time Intervals such as to determine at which instances a control channel may address a user equipment in a power saving mode or non-power saving mode;   defining a first, wideband mapping pattern for user equipments in a non-power saving mode;   defining a second, narrowband mapping pattern for user equipments in a power saving mode; and   transmitting, during Transmission Time Intervals of a subset associated to a respective power mode, said information over the control channel by using the mapping pattern that is defined for the respective power mode of the user equipment.   
     
     
         2 . The method according to  claim 1 , whereby said second mapping pattern is used for signalling of indications pointing to a certain message. 
     
     
         3 . The method according to  claim 1 , whereby said second mapping pattern is used for paging and/or broadcast messages. 
     
     
         4 . The method according to  claim 1 , whereby using said second mapping pattern implies mapping on a pseudo-random set of subcarriers. 
     
     
         5 . The method according to  claim 1 , whereby using said first mapping pattern implies a mapping on a subset of non-contiguous subcarriers covering a major part of the system bandwidth. 
     
     
         6 . The method according to  claim 1 , whereby information is allowed to be transmitted over the control channel to user equipments in non-power saving modes by using the second mapping pattern if no information is to be transmitted to user equipments in a power saving mode. 
     
     
         7 . The method according to  claim 1 , whereby using said second mapping pattern implies a mapping on a subset of contiguous subcarriers. 
     
     
         8 . The method according to  claim 1 , whereby said control channel is interleaved on a wide or narrow bandwidth depending on the power mode of the user equipment. 
     
     
         9 . The method according to  claim 1 , whereby the communication network applies Orthogonal Frequency Division Multiplexing (OFDM). 
     
     
         10 . An arrangement for efficiently utilizing radio resources in a communication network, said arrangement included in or associated to a communication network node for transmitting information on control channels to one or more user equipments, comprising
 a first unit for providing subsets of Transmission Time Intervals such as to determine at which instances a control channel may address a user equipment in a power saving mode or non-power saving mode;   a second unit for providing a first, wideband mapping pattern for user equipments in a non-power saving mode and a second, narrowband mapping pattern for user equipments in a power saving mode; and   a transmitter adapted to transmit, during Transmission Time Intervals of pre-defined subsets associated to a respective power mode, said information over the control channel by using the mapping pattern that is defined for the respective power mode of the user equipment.   
     
     
         11 . The arrangement according to  claim 10 , wherein the communication network applies Orthogonal Frequency Division Multiplexing (OFDM).