| 摘要 |
A mobile communications system communicates data to and/or from mobile communications devices. The mobile communications system provides a wireless access interface for communicating data to and/or from the mobile communications devices, the wireless access interface providing on a downlink first carrier, the first carrier providing a plurality of communications resource elements across a first frequency range for communicating data, and providing a plurality of communications resource elements within a second frequency range which is within and smaller than the first frequency range. The wireless access interface provided by the base stations includes a plurality of time divided sub-frames, each sub-frame including the plurality of communications resource elements of the first frequency range and the plurality of the communications resource elements of the second frequency range, and each sub-frame includes a first wideband control channel in a part of each sub- frame having a bandwidth corresponding substantially to the first frequency range, and a second narrow band control channel in a second part of each sub-frame and having a bandwidth which is less than the first wideband control channel and a duration of the second narrow band control channel within the sub-frame is greater than a duration of the first wideband control channel within the sub- frame. The second narrow band control channel is configured for communicating control information to both the first mobile communications devices and the second mobile communications devices and forms part of the plurality of the communications resource elements of the second frequency range of the second carrier. By arranging for the narrow band control channel to be within the virtual carrier and to communicate control information to both first full capability communications devices and second reduced capability communications devices, the second reduced capability devices can access the narrow band control channel which is shared with the first full-capability mobile devices. This arrangement makes more use of the communications resources available to the communications system. |
