Communications device and method
View Patent ↗A mobile communications system communicates data to/from mobile communications devices, and provides a wireless access interface communicating data to/from the mobile communications devices, on a downlink first carrier providing plural communications resource elements across a first frequency range for communicating data, and within a second frequency range within and smaller than the first frequency range. The wireless access interface includes plural time divided sub-frames, each sub-frame including plural communications resource elements of the first frequency range and plural communications resource elements of the second frequency range. By arranging for a narrow band control channel to be within a 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, to make use of communications resources available to the communications system.
1. A communications device for transmitting data to or receiving data from a mobile communications network, the mobile communications network providing a wireless access interface for the communications device, the communications device comprising: circuitry configured to transmit data to base stations of the mobile communications network via the wireless access interface provided by the base stations, wherein the wireless access interface provides a downlink including a 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 forming a second carrier, 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 first part of each sub-frame having a bandwidth corresponding substantially to the first frequency range, a second narrow band control channel in a second part of each sub-frame that follows the first part, the second narrow band control channel residing within the second carrier and spanning fewer than all frequencies spanned by the second carrier, the second narrow band control channel beginning in time immediately after the first wideband control channel and spanning in time an entirety of the second part of each sub-frame, the first wideband control channel not including the second narrow band control channel, and a third narrow band control channel in the second part of each sub-frame that follows the first part, the third narrow band control channel residing within the second carrier and spanning fewer than all frequencies spanned by the second carrier, the third narrow band control channel spanning in time an entirety of the second part of each sub-frame, the first wideband control channel not including the third narrow band control channel, the third narrow band control channel being separate from the second narrow band control channel,
wherein each sub-frame includes a narrow band shared data channel for communicating data in the second part of each sub-frame, the narrow band shared data channel residing within the second carrier and spanning fewer than all frequencies spanned by the second carrier, the narrow band shared data channel spanning in time an entirety of the second part of each sub-frame, the first wideband control channel not including the narrow band shared data channel,
wherein the second narrow band control channel, the narrow band shared data channel and the third narrow band control channel are contiguous within the frequency range of the second carrier,
and operate with a receiver band width corresponding to the second frequency range and receive control information from the second narrow band control channel to access the plurality of the communications resource elements of the second frequency range of the second carrier,
wherein the circuitry is configured to receive resource allocation messages in the second narrow band control channel and the third narrow band control channel, the resource allocation messages providing an indication of communication resources of the narrow band shared data channel that have been allocated to the communications device.
2. The communications device as claimed in claim 1 , wherein the circuitry is configured to receive second resource allocation messages from the second narrow band control channel, the second resource allocation messages providing an indication of communications resource elements in the second frequency range of the second carrier which have been allocated to the communications device, the resources allocated to the communications device being allocated within the second frequency range of the second carrier.
3. The communications device as claimed in claim 1 , wherein the circuitry is configured to receive common control information from a control channel formed within the second frequency range of the second carrier, the common control information including signaling information for use by the communications device to transmit and receive data via the plurality of communications resource elements of the second frequency range.
4. The communications device as claimed in claim 1 , wherein the communications device is configured to operate in accordance with a Long Term Evolution (LTE) based system, and the wide band control channel is an Physical Downlink Control Channel (PDCCH), the narrow band control channel is an Enhanced Physical Downlink Control Channel (EPDCCH) and a plurality of the communications resource elements form part of a Physical Downlink Shared Channel (PDSCH).
5. The communications device of claim 1 , wherein the second narrow band control channel, the narrow band shared data channel and the third narrow band control channel are contiguous within the frequency range of the second carrier and comprise the entirety of the second carrier.
6. The communications device of claim 1 , wherein the narrow band shared data channel resides in a frequency range in the second carrier between the second narrow band control channel and the third narrow band control channel.
7. A method of operating a communications device to transmit data to or receive data from a mobile communications network, the mobile communications network providing a wireless access interface for the communications device, the wireless access interface providing, on a downlink, a 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 forming a second carrier, the method comprising: transmitting, with circuitry, data to base stations of the mobile communications network via the wireless access interface provided by the base stations; and receiving, with the circuitry, data from the base stations of the mobile communications network via the wireless access interface provided by the base stations, wherein the data is received in a receiver band width corresponding to the second frequency range, the data received from the base stations being provided in a downlink including 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 first 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 that follows the first part, the second narrow band control channel residing within the second carrier and spanning fewer than all frequencies spanned by the second carrier, the second narrow band control channel beginning in time immediately after the first wideband control channel and spanning in time an entirety of the second part of each sub-frame, the first wideband control channel not including the second narrow band control channel, and a third narrow band control channel in the second part of each sub-frame that follows the first part, the third narrow band control channel residing within the second carrier and spanning fewer than all frequencies spanned by the second carrier, the third narrow band control channel spanning in time an entirety of the second part of each sub-frame, the first wideband control channel not including the third narrow band control channel, the third narrow band control channel being separate from the second narrow band control channel,
wherein each sub-frame includes a narrow band shared data channel for communicating data in the second part of each sub-frame, the narrow band shared data channel residing within the second carrier and spanning fewer than all frequencies spanned by the second carrier, the narrow band shared data channel spanning in time an entirety of the second part of each sub-frame, the first wideband control channel not including the narrow band shared data channel,
wherein the second narrow band control channel, the narrow band shared data channel and the third narrow band control channel are contiguous within the frequency range of the second carrier;
and the method further comprises: receiving, with circuitry, control information from the second narrow band control channel to access the plurality of the communications resource elements of the second frequency range of the second carrier, and further comprising:
receiving resource allocation messages in the second narrow band control channel and the third narrow band control channel, the resource allocation messages providing an indication of communication resources of the narrow band shared data channel that have been allocated to the communications device.
8. The method as claimed in claim 7 , further comprising: receiving second resource allocation messages from the second narrow band control channel, the second resource allocation messages providing an indication of communications resource elements in the second frequency range of the second carrier which have been allocated to the communications device, the resources allocated to the communications device being allocated within the second frequency range of the second carrier.
9. The method as claimed in claim 7 , further comprising: receiving common control information from a control channel formed within the second frequency range of the second carrier, the common control information including signaling information for use by the communications devices to transmit and receive data via the plurality of communications resource elements of the second frequency range.
10. The method as claimed in claim 7 , wherein the communications device is configured to operate in accordance with a Long Term Evolution system, and the wide band control channel is an Physical Downlink Control Channel (PDCCH), the narrow band control channel is an Enhanced Physical Downlink Control Channel (EPDCCH) and a plurality of the communications resource elements form part of a Physical Downlink Shared Channel (PDSCH).
11. The method of claim 7 , wherein the second narrow band control channel, the narrow band shared data channel and the third narrow band control channel are contiguous within the frequency range of the second carrier and comprise the entirety of the second carrier.
12. The method of claim 7 , wherein the narrow band shared data channel resides in a frequency range in the second carrier between the second narrow band control channel and the third narrow band control channel.