HARQ for dynamic change of the TDD UL/DL configuration in LTE TDD systems
View Patent ↗Systems, methods, and apparatuses are directed to reconfiguring a time division duplex (TDD) uplink/downlink (UL/DL) configuration. A first TDD UL/DL configuration can be identified for a first radio frame. A second TDD UL/DL configuration can be identified for a second radio frame adjacent the first radio frame. The second TDD UL/DL configuration can be identified based, at least in part, on one or more subframes of the second TDD UL/DL configuration that can communicate hybrid automatic repeat request (HARQ) acknowledgement/negative acknowledgement (ACK/NACK) indicators for corresponding subframes of the first TDD UL/DL configuration.
1. A method of reconfiguring a time division duplex (TDD) uplink/downlink (UL/DL) configuration, the method comprising:
identifying, at a base station, a first TDD UL/DL predetermined configuration for a first radio frame;
communicating data using the first TDD UL/DL predetermined configuration in the first radio frame;
in response to a change in traffic ratio between UL and DL transmissions, identifying, at the base station, a second TDD UL/DL predetermined configuration for a second radio frame adjacent the first radio frame, the second TDD UL/DL predetermined configuration identified based, at least in part, on one or more subframes of the second TDD UL/DL predetermined configuration that can communicate at least one hybrid automatic repeat request (HARQ) acknowledgement/negative acknowledgement (ACK/NACK) indicator for a corresponding subframe of the first TDD UL/DL predetermined configuration, wherein the first TDD UL/DL predetermined configuration supports a greater number of HARQ processes than the second TDD UL/DL predetermined configuration, the HARQ processes are uplink (UL) HARQ processes
communicating data using the second TDD UL/DL predetermined configuration in the second radio frame;
storing excess UL HARQ processes in a queue; and
upon receiving a negative new data indicator, executing a first UL HARQ process of the UL HARQ processes stored in the queue.
2. The method of claim 1 , further comprising communicating an ACK indicator prior to the reconfiguring of the TDD UL/DL predetermined configuration.
3. The method of claim 1 , further comprising reconfiguring the TDD UL/DL predetermined configuration for the second radio frame based on the identified second TDD UL/DL predetermined configuration.
4. The method of claim 1 , wherein the first TDD UL/DL predetermined configuration and the second TDD UL/DL predetermined configuration are defined by an LTE standard.
5. A method of reconfiguring a time division duplex (TDD) uplink/downlink (UL/DL) configuration, the method comprising:
identifying, at a base station, a first TDD UL/DL predetermined configuration for a first radio frame;
communicating data using the first TDD UL/DL predetermined configuration in the first radio frame;
in response to a change in traffic ratio between UL and DL transmissions, identifying, at the base station, a second TDD UL/DL predetermined configuration for a second radio frame adjacent the first radio frame, the second TDD UL/DL predetermined configuration identified based, at least in part, on one or more subframes of the second TDD UL/DL predetermined configuration that can communicate at least one hybrid automatic repeat request (HARQ) acknowledgement/negative acknowledgement (ACK/NACK) indicator for a corresponding subframe of the first TDD UL/DL predetermined configuration, wherein the first TDD UL/DL predetermined configuration supports a greater number of HARQ processes than the second TDD UL/DL predetermined configuration, and the second TDD UL/DL predetermined configuration is associated with a second number of HARQ buffers;
communicating data using the second TDD UL/DL predetermined configuration in the second radio frame; and
executing a second number of HARQ processes associated with the first TDD UL/DL predetermined configuration, the second number of HARQ processes equal to the second number of HARQ buffers.
6. A base station for reconfiguring a time division duplex (TDD) uplink/downlink (UL/DL) configuration, comprising:
one or more processors configured to:
identify, at the base station, a first TDD UL/DL predetermined configuration for a first radio frame;
communicate data using the first TDD UL/DL predetermined configuration in the first radio frame;
in response to a change in traffic ratio between UL and DL transmissions, identify, at the base station, a second TDD UL/DL predetermined configuration for a second radio frame adjacent the first radio frame, the second TDD UL/DL predetermined configuration identified based, at least in part, on one or more subframes of the second TDD UL/DL predetermined configuration that can communicate at least one hybrid automatic repeat request (HARQ) acknowledgement/negative acknowledgement (ACK/NACK) indicator for a corresponding subframe of the first TDD UL/DL predetermined configuration, wherein the first TDD UL/DL predetermined configuration supports a greater number of HARQ processes than the second TDD UL/DL predetermined configuration, the HARQ processes are uplink (UL) HARQ processes
communicate data using the second TDD UL/DL predetermined configuration in the second radio frame;
store excess UL HARQ processes in a queue; and
upon receiving a negative new data indicator, execute a first UL HARQ process of the UL HARQ processes stored in the queue.
7. The base station of claim 6 , wherein the first TDD UL/DL predetermined configuration and the second TDD UL/DL predetermined configuration are defined by an LTE standard.
8. A non-transitory computer-readable medium containing instructions which, when executed, cause a computing device to perform operations comprising:
identifying, at a base station, a first time division duplex (TDD) uplink/downlink (UL/DL) predetermined configuration for a first radio frame;
communicating data using the first TDD UL/DL predetermined configuration in the first radio frame;
in response to a change in traffic ratio between UL and DL transmissions, identifying, at the base station, a second TDD UL/DL predetermined configuration for a second radio frame adjacent the first radio frame, the second TDD UL/DL predetermined configuration identified based, at least in part, on one or more subframes of the second TDD UL/DL predetermined configuration that can communicate at least one hybrid automatic repeat request (HARQ) acknowledgement/negative acknowledgement (ACK/NACK) indicator for a corresponding subframe of the first TDD UL/DL predetermined configuration, wherein the first TDD UL/DL predetermined configuration supports a greater number of HARQ processes than the second TDD UL/DL predetermined configuration, and the second TDD UL/DL predetermined configuration is associated with a second number of HARQ buffers;
communicating data using the second TDD UL/DL predetermined configuration in the second radio frame; and
executing a second number of HARQ processes associated with the first TDD UL/DL predetermined configuration, the second number of HARQ processes equal to the second number of HARQ buffers.