TRANSMISSION OF CONTROL INFORMATION TO REDUCED BANDWIDTH TERMINALS

摘要

A method of receiving data at a communications terminal from an OFDM wireless communications network which provides a wireless access interface for communicating the data using a plurality of OFDM sub-carriers comprises receiving from a first control channel having a bandwidth corresponding to a first frequency band providing a first plurality of OFDM sub-carriers are source allocation message allocating communications resources of a second group of OFDM sub-carriers. The second group of the plurality of OFDM sub-carriers is smaller than the first group of the plurality of OFDM sub-carriers and the second frequency band is selected from within the first frequency band to form a virtual carrier. The method includes receiving from a second control channel within the second frequency band within the second group of OFDM sub-carriers control information which is specific to the communications terminal operating to receive the data via the second group of OFDM sub-carriers. The communications terminal thereby receives resource allocation messages from the first control channel to allocate resources within the second frequency band forming the virtual carrier and to receive control information,which is specific to the communications terminal,which is receiving data from the second frequency band of the virtual carrier via a second control channel. Accordingly, there is provided a logical separation of full bandwidth LTE type terminals and communications terminals of a reduced bandwidth of the second type in respect of the transmission of control information, but uses the same resource allocation messages for both the full-bandwidth LTE terminals and the reduced bandwidth terminals of the second type thereby improving compatibility with conventional LTE networks.