Methods and system for communicating control information using carrier aggregation

1. An apparatus, comprising:

a radio frequency (RF) transceiver to receive a first message over a first carrier in a first band in a downlink sub-frame of a first radio frame in a communications link, the communications link comprising interband carriers aggregated over a primary and a secondary cell;

a processor; and

a reply message assignment module operable on the processor to:

determine a first time division duplex uplink-downlink (UL-DL) configuration in which transmission is received;

map the first UL-DL configuration to a first UL-DL group of a multiplicity of UL-DL groups, the first UL-DL group comprising a set of UL-DL configurations sharing a common uplink sub-frame set of each radio frame; and

adjust timing of a reply/acknowledge message to be sent by the transceiver in response to the first message so as to coincide with a predetermined uplink sub-frame of a radio frame.

2. The apparatus of claim 1 , the RF transceiver arranged to receive the first message over the secondary cell and to send the reply message over the primary cell.

3. The apparatus of claim 1 , the reply message assignment module comprising an adapted downlink association set index, the adapted downlink association set index mapping, for each of a multiplicity of uplink-downlink configurations, one or more downlink sub-frames for carrying the first message to a common uplink sub-frame of a radio frame for carrying the reply message.

4. The apparatus of claim 3 , the adapted downlink association set index comprising a single sub-frame of a radio frame for carrying the reply message in all uplink-downlink configurations.

5. The apparatus of claim 3 , the radio frame comprising a time division duplex radio frame having ten sub-frames, each uplink-downlink configuration comprising an arrangement of uplink subframes and downlink subframes that is different from each other uplink-downlink configuration.

6. A system, comprising:

a radio frequency (RF) transceiver to receive a first message over a first carrier in a first band in a downlink sub-frame of a first radio frame in a communications link, the communications link comprising interband carriers distributed over a primary and secondary cell;

a processor;

a reply message assignment module operable on the processor to:

determine a first time division duplex uplink-downlink (UL-DL) configuration employed by the system;

map the first UL-DL configuration to a first UL-DL group of a multiplicity of UL-DL groups, the first UL-DL group comprising a set of UL-DL configurations sharing a common uplink sub-frame set of each radio frame; and

adjust timing of a reply message to be sent by the RF transceiver in response to the first message so as to coincide with a common uplink sub-frame of the common uplink sub-frame set of each radio frame; and

a digital display to present information received by the RF transceiver over the interband carriers.

7. The system of claim 6 , the RF transceiver arranged to receive the first message over the secondary cell and to send the reply message over the primary cell.

8. The system of claim 6 , the common uplink sub-frame set comprising a multiplicity of sub-frames in each radio frame.

9. The system of claim 6 , the reply message assignment module comprising an adapted downlink association set index, the adapted downlink association set index mapping each UL-DL configuration to a given UL-DL group of the multiplicity of UL-DL groups, each UL-DL group comprising a set of UL-DL configurations sharing a common uplink sub-frame set of each radio frame.

10. A non-transitory computer-readable storage medium for receiving a first message over a first carrier in a first band in a downlink sub-frame of a first radio frame in a communications link, the communications link comprising interband carriers aggregated over a primary and a secondary cell, the non-transitory computer-readable storage medium comprising instructions that when executed by a processor enable a system to:

determine a first time division duplex uplink-downlink (UL-DL) configuration employed by the system;

map the first UL-DL configuration to a first UL-DL group of a multiplicity of UL-DL groups, the first UL-DL group comprising a set of UL-DL configurations sharing a common uplink sub-frame set of each radio frame; and

adjust timing of a reply message to be sent by the RF transceiver in response to the first message so as to coincide with a common uplink sub-frame of the common uplink sub-frame set of each radio frame.

11. The non-transitory computer-readable storage medium of claim 10 , comprising instructions that when executed by a processor enable a system to map each UL-DL configuration to a given UL-DL group of the multiplicity of UL-DL groups, each UL-DL group comprising a set of UL-DL configurations sharing a common uplink sub-frame set of each radio frame.

12. The non-transitory computer-readable storage medium of claim 10 , comprising instructions that when executed by a processor enable a system to map a first downlink subframe to a first uplink subframe in a first radio frame and to map a second downlink subframe to a second uplink subframe in a second radio frame.