Transmission of control information to reduced bandwidth terminals

• US 10,178,677 B2
• Filed: 12/02/2013
• Issued: 01/08/2019
• Est. Priority Date: 12/03/2012
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Webb, Matthew, Wakabayashi, Hideji, Morioka, Yuichi
• Primary Examiner(s): Chu, Wutchung
• Application Number:
  US14/442,179
• Publication Number:
  US 20160295568A1
• Time in Patent Office: 1,863 Days
• CPC Class Codes: H04L 27/2601 Multicarrier modulation systems
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/0037 Inter-user or inter-terminal allocation
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04L 5/0064 Rate requirement of the data, e.g. scalable bandwidth, data priority
• CPC Class Codes: H04L 5/0094 Indication of how sub-channels of the path are allocated
• CPC Class Codes: H04W 52/0212 managed by the network, e.g. network or access point is master and terminal is slave
• CPC Class Codes: H04W 72/0446 Resources in time domain, e.g. slots or frames
• CPC Class Codes: H04W 72/0453 Resources in frequency domain, e.g. a carrier in FDMA
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal
• CPC Class Codes: H04W 72/51 based on terminal or device properties
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A method receiving data at a communications terminal from an OFDM wireless communications network including a wireless access interface communicating the data using plural OFDM sub-carriers includes: receiving from a first control channel having a bandwidth corresponding to a first frequency band providing first plural OFDM sub-carriers a resource allocation message allocating communications resources of a second group of OFDM sub-carriers; and receiving from a second control channel within the second frequency band within the second group of OFDM sub-carriers control information specific to the communications terminal operating to receive the data via the second group of OFDM sub-carriers. The communications terminal receives resource allocation messages from the first control channel to allocate resources within the second frequency band forming a virtual carrier and to receive control information specific to the communications terminal, which receives data from the second frequency band of the virtual carrier via a second control channel.

Claims

1. A communications terminal comprising:

a transceiver configured to receive data from a wireless communications network transmitted via a wireless access interface provided by the wireless communications network using a plurality of OFDM sub-carriers, and

a controller configured to receive a resource allocation message, which allocates resources to the communications terminal for receiving the data from the wireless communications network, wherein the controller is configured to control the transceiver to

receive from a physical downlink control channel (PDCCH) the resource allocation message, the PDCCH having a bandwidth corresponding to a first frequency band, the resource allocation message allocating the communications resources within a second frequency band, the first frequency band providing a first group of the plurality of OFDM sub-carriers within the first frequency band, and the second frequency band being formed from a second group of the plurality of OFDM sub-carriers within the second frequency band, the second group of the plurality of OFDM sub-carriers being smaller than the first group of the plurality of OFDM sub-carriers and the second frequency band being selected from within the first frequency band to form a virtual carrier, and

receive control information from a virtual carrier-physical downlink control channel (VC-PDCCH) within the second frequency band from the second group of OFDM sub-carriers, wherein the control information allocates communication resources for receiving the data by the communications terminal from the second group of OFDM sub-carriers; and

receive data from within the second frequency band based on a combination of resources allocated for data communication within the second frequency band identified in the resource allocation message received from the PDCCH and resources allocated for data communication within the second group of OFDM sub-carriers identified in the control information received from the VC-PDCCH,

wherein a location of the VC-PDCCH is not included in the resource allocation message received from the PDCCH and is predefined in the communications terminal,

wherein the PDCCH and the VC-PDCCH are located at opposite ends of a sub-frame, relative to time, and

wherein the VC-PDCCH occupies less than one half of the second frequency band.

2. The communications terminal according to claim 1, wherein the control information includes an indication of the location of the second frequency bandwidth providing the second group of OFDM sub-carriers for one or more of the sub-frames.

3. The communications terminal according to claim 1, wherein the resource allocation message is transmitted via the PDCCH to allocate resources to the communications terminal, and the control information transmitted via the VC-PDCCH provides a second resource allocation message to the communications terminal to allocate resources from the second bandwidth of the second group of OFDM sub-carriers.

4. The communications terminal according to claim 1, wherein the control information includes an indication that the data is to be transmitted more than once, and the controller is configured in combination with the transceiver to receive the data more than once from the second frequency bandwidth using the second group of OFDM sub-carriers.

5. The communications terminal according to claim 1, wherein the control information includes an indication that the communications terminal can sleep for a predetermined time, and the controller is configured in combination with the transceiver to respond to the sleep indication to enter a state of a reduced power consumption.

6. The communications terminal according to claim 1, wherein the controller is configured in combination with the transceiver to receive the resource allocation message from the PDCCH, the resource allocation message allocating resources to the communications terminal within the second frequency band of the virtual carrier and to receive the control information from the VC-PDCCH, the control information providing a second resource allocation message to allocate resources from the second bandwidth of the second group of OFDM sub-carriers.

7. The communications terminal according to claim 6, wherein the controller is configured in combination with the transceiver to receive the resource allocation message from the PDCCH, the resource allocation message allocating resources to the communications terminal as a member of a group of the communications terminals and to receive the second resource allocation message from the VC-PDCCH providing an allocation of the resources of the second group of OFDM sub-carriers within the second frequency bandwidth to the communications terminals as a member of the group of communications terminals.

8. The communications terminal according to claim 1, wherein the wireless access interface provides a third group of OFDM sub-carriers within a third frequency band, the third group of the plurality of OFDM sub-carriers being smaller than the first group of the plurality of OFDM sub-carriers and the third frequency band being selected from within the first frequency band and mutually exclusive from the second group of OFDM sub-carriers of the second frequency band to form a second virtual carrier, and the controller is configured in combination with the transceiver to receive the control information from the VC-PDCCH, which includes a second resource allocation message providing an indication of a system information which is common to other communications terminals which are allocated communications resources of the second group of OFDM sub-carriers and the third group of OFDM sub-carriers of the first and second virtual carriers.

9. The communications terminal according to claim 1, wherein the PDCCH has a bandwidth which corresponds to the first frequency band of the first group of OFDM sub-carriers and the VC-PDCCH within the second frequency band is formed from a plurality of the OFDM sub-carriers of the second group of OFDM sub-carriers and has a duration which exceeds the duration of the first control channel.

10. The communications terminal according to claim 1, wherein the PDCCH has a bandwidth corresponding to the first frequency band is at a first temporal position within a sub-frame, and the VC-PDCCH in the second frequency band of the second group of OFDM sub-carriers is in a second temporal position within a sub-frame.

11. The communications terminals according to claim 1, wherein

the wireless communications network is arranged in accordance with 3GPP Long Term Evolution (LTE) specifications.

12. A method of receiving data at a communications terminal from a mobile communications network transmitted via a wireless access interface provided by the wireless communications network using a plurality of OFDM sub-carriers, the method comprising:

receiving a resource allocation message, which allocates resources to the communications terminal for receiving the data from the wireless communications network, the receiving the resource allocation message including

receiving from a physical downlink control channel (PDCCH) the resource allocation message, the PDCCH having a bandwidth corresponding to a first frequency band, the resource allocation message allocating the communications resources within a second frequency band, the first frequency band providing a first group of the plurality of OFDM sub-carriers within the first frequency band, and the second frequency band being formed from a second group of the plurality of OFDM sub-carriers within the second frequency band, the second group of the plurality of OFDM sub-carriers being smaller than the first group of the plurality of OFDM sub-carriers and the second frequency band being selected from within the first frequency band to form a virtual carrier, and the method includes

receiving control information from a virtual carrier-physical downlink control channel (VC-PDCCH) within the second frequency band from the second group of OFDM sub-carriers, wherein the control information allocates communication resources for receiving the data by the communications terminal from the second group of OFDM sub-carriers; and

receiving data from within the second frequency band based on a combination of resources allocated for data communication within the second frequency band identified in the resource allocation message received from the PDCCH and resources allocated for data communication within the second group of OFDM sub-carriers identified in the control information received from the VC-PDCCH,

wherein a location of the VC-PDCCH is not included in the resource allocation message received from the PDCCH and is predefined in the communications terminal,

wherein the PDCCH and the VC-PDCCH are located at opposite ends of a sub-frame, relative to time, and

wherein the VC-PDCCH occupies less than one half of the second frequency band.

13. The method according to claim 12, wherein the control information includes an indication of the location of the second frequency bandwidth providing the second group of OFDM sub-carriers for one or more of the sub-frames.

14. The method according to claim 12, wherein the receiving the resource allocation message includes receiving the resource allocation message from the PDCCH to allocate resources to the communications terminal, and the receiving the control information from the VC-PDCCH includes receiving a second resource allocation message to allocate resources to the communications terminal from the second bandwidth of the second group of OFDM sub-carriers.

15. The method according to claim 12, wherein the PDCCH having a bandwidth corresponding to the first frequency band is at a first temporal position within a sub-frame, and the VC-PDCCH in the second frequency band of the second group of OFDM sub-carriers is in a second temporal position within a sub-frame.