Channel state information and adaptive modulation and coding design for long-term evolution machine type communications
A method, an apparatus, and a computer program product for wireless communication are provided. The apparatus may be a UE. The UE determines CSI. The UE determines whether to send the CSI based on at least one of a timer or a threshold. The UE sends the CSI upon determining to send the CSI. The UE may send the CSI in a MAC header upon determining to send the CSI. When the UE determines whether to send the CSI based on the threshold, the UE may determine whether to send the CSI based on a difference between the CSI and reference CSI. The UE may determine the reference CSI based on at least one of previously reported CSI, fixed CSI, or an MCS of a received data transmission from a base station. The UE may send CSI to the base station in an initial connection setup with the base station.
1. A method of wireless communication of a user equipment (UE), comprising:
receiving a transmission time interval (TTI) bundling transmission from a base station;
decoding a subset of the TTI bundling transmission; and
sending an acknowledgment to the base station to terminate the TTI bundling transmission early upon decoding the subset of the TTI bundling transmission,
wherein channel state information (CSI) is indicated to the base station based on a percentage of the TTI bundling transmission received by the UE, wherein a TTI bundling size is based on the percentage of the TTI bundling transmission received by the UE.
2. The method of claim 1 , further comprising receiving data modulated and coded with a modulation and coding scheme (MCS) from the base station, wherein the MCS is based on the percentage of the TTI bundling transmission received by the UE.
3. A method of wireless communication of a user equipment (UE), comprising:
sending an uplink transmission to a base station; and
receiving a data transmission from the base station, the data transmission having a modulation and coding scheme (MCS) determined based on the uplink transmission and a transmission time interval (TTI) bundling size that is also determined based on the uplink transmission;
wherein the data transmission includes a request for the UE to adjust a subsequent uplink transmission if one or both of the determined MCS or the determined TTI bundling size differ from respective values that the UE expected.
4. A method of wireless communication of a user equipment (UE), comprising:
determining a first transmission time interval (TTI) bundling size based on an estimated channel between a base station and the UE;
receiving data with a second TTI bundling size from the base station;
determining whether the second TTI bundling size differs from the first TTI bundling size by more than a threshold; and
sending channel state information (CSI) after determining that the second TTI bundling size differs from the first TTI bundling size by more than the threshold.
5. The method of claim 4 , wherein the threshold corresponds to a bundling size difference.
6. The method of claim 4 , wherein the CSI is sent when a difference between the first bundling size and the second bundling size is greater than the threshold.
7. A method of wireless communication of a base station, comprising:
sending a first transmission time interval (TTI) bundling transmission to a user equipment (UE);
receiving an acknowledgment from the UE indicating that reception of the TTI bundling transmission was terminated early by the UE resulting in a percentage of the first TTI bundling transmission being received by the UE;
determining a modulation and coding scheme (MCS) based on the percentage of the first TTI bundling transmission received by the UE; and sending a second TTI bundling transmission to the UE modulated and coded with the MCS;
wherein a TTI bundling size of the second TTI bundling transmission is based on the percentage of the first TTI bundling transmission received by the UE.
8. A method of wireless communication of a base station, comprising:
receiving an uplink transmission from a user equipment (UE);
determining a modulation and coding scheme (MCS) based on the received uplink transmission;
determining a transmission time interval (TTI) bundling size based on the received uplink transmission; and
sending a data transmission to the UE based on both the determined MCS and the determined TTI bundling size,
wherein the data transmission includes a request for the UE to adjust a subsequent uplink transmission if one or both of the determined MCS or the determined TTI bundling size differ from respective values that the UE expected.
9. An apparatus for wireless communication of a user equipment (UE), comprising:
a memory; and
at least one processor coupled to the memory and configured to:
receive a transmission time interval (TTI) bundling transmission from a base station;
decode a subset of the TTI bundling transmission; and
send an acknowledgment to the base station to terminate the TTI bundling transmission early upon decoding the subset of the TTI bundling transmission,
wherein channel state information (CSI) is indicated to the base station based on a percentage of the TTI bundling transmission received by the UE, wherein a TTI bundling size is based on the percentage of the TTI bundling transmission received by the UE.
10. The apparatus of claim 9 , wherein the at least one processor is further configured to:
receive data modulated and coded with a modulation and coding scheme (MCS) from the base station, wherein the MCS is based on the percentage of the TTI bundling transmission received by the UE.
11. An apparatus for wireless communication of a user equipment (UE), comprising:
a memory; and
at least one processor coupled to the memory and configured to:
send an uplink transmission to a base station; and
receive a data transmission from the base station, the data transmission having a modulation and coding scheme (MCS) determined based on the uplink transmission and a transmission time interval (TTI) bundling size that is also determined based on the uplink transmission;
wherein the data transmission includes a request for the UE to adjust a subsequent uplink transmission if one or both of the determined MCS or the determined TTI bundling size differ from respective values that the UE expected.
12. An apparatus for wireless communication of a user equipment (UE), comprising:
a memory; and
at least one processor coupled to the memory and configured to:
determine a first transmission time interval (TTI) bundling size based on an estimated channel between a base station and the UE;
receive data with a second TTI bundling size from the base station;
determine whether the second TTI bundling size differs from the first TTI bundling size by more than a threshold; and
send channel state information (CSI) after determining that the second TTI bundling size differs from the first TTI bundling size by more than the threshold.
13. The apparatus of claim 12 , wherein the threshold corresponds to a bundling size difference.
14. The apparatus of claim 12 , wherein the CSI is sent when a difference between the first bundling size and the second bundling size is greater than the threshold.
15. An apparatus for wireless communication of a base station, comprising:
a memory; and
at least one processor coupled to the memory and configured to:
send a first transmission time interval (TTI) bundling transmission to a user equipment (UE);
receive an acknowledgment from the UE indicating that reception of the TTI bundling transmission was terminated early by the UE resulting in a percentage of the first TTI bundling transmission being received by the UE;
determine a modulation and coding scheme (MCS) based on the percentage of the first TTI bundling transmission received by the UE; and
send a second TTI bundling transmission to the UE modulated and coded with the MCS;
wherein a TTI bundling size of the second TTI bundling transmission is based on the percentage of the first TTI bundling transmission received by the UE.
16. An apparatus for wireless communication of a base station, comprising:
a memory; and
at least one processor coupled to the memory and configured to:
receive an uplink transmission from a user equipment (UE);
determine a modulation and coding scheme (MCS) based on the received uplink transmission;
determine a transmission time interval (TTI) bundling size based on the received uplink transmission; and
send a data transmission to the UE based on both the determined MCS and the determined TTI bundling size,
wherein the data transmission includes a request for the UE to adjust a subsequent uplink transmission if one or both of the determined MCS or the determined TTI bundling size differ from respective values that the UE expected.
17. A non-transitory computer-readable medium storing computer executable code for wireless communication of a user equipment (UE), the code when executed by a processor causes the processor to:
receive a transmission time interval (TTI) bundling transmission from a base station;
decode a subset of the TTI bundling transmission; and
send an acknowledgment to the base station to terminate the TTI bundling transmission early upon decoding the subset of the TTI bundling transmission,
wherein channel state information (CSI) is indicated to the base station based on a percentage of the TTI bundling transmission received by the UE, wherein a TTI bundling size is based on the percentage of the TTI bundling transmission received by the UE.
18. A non-transitory computer-readable medium storing computer executable code for wireless communication of a user equipment (UE), the code when executed by a processor causes the processor to:
send an uplink transmission to a base station; and
receive a data transmission from the base station, the data transmission having a modulation and coding scheme (MCS) determined based on the uplink transmission and a transmission time interval (TTI) bundling size that is also determined based on the uplink transmission;
wherein the data transmission includes a request for the UE to adjust a subsequent uplink transmission if one or both of the determined MCS or the determined TTI bundling size differ from respective values that the UE expected.
19. A non-transitory computer-readable medium storing computer executable code for wireless communication of a user equipment (UE), the code when executed by a processor causes the processor to:
determine a first transmission time interval (TTI) bundling size based on an estimated channel between a base station and the UE;
receive data with a second TTI bundling size from the base station;
determine whether the second TTI bundling size differs from the first TTI bundling size by more than a threshold; and
send channel state information (CSI) after determining that the second TTI bundling size differs from the first TTI bundling size by more than the threshold.
20. A non-transitory computer-readable medium storing computer executable code for wireless communication of a base station, the code when executed by a processor causes the processor to:
send a first transmission time interval (TTI) bundling transmission to a user equipment (UE);
receive an acknowledgment from the UE indicating that reception of the TTI bundling transmission was terminated early by the UE resulting in a percentage of the first TTI bundling transmission being received by the UE;
determine a modulation and coding scheme (MCS) based on the percentage of the first TTI bundling transmission received by the UE; and
send a second TTI bundling transmission to the UE modulated and coded with the MCS;
wherein a TTI bundling size of the second TTI bundling transmission is based on the percentage of the first TTI bundling transmission received by the UE.
21. A non-transitory computer-readable medium storing computer executable code for wireless communication of a base station, the code when executed by a processor causes the processor to:
receive an uplink transmission from a user equipment (UE);
determine a modulation and coding scheme (MCS) based on the received uplink transmission;
determine a transmission time interval (TTI) bundling size based on the received uplink transmission; and
send a data transmission to the UE based on both the determined MCS and the determined TTI bundling size,
wherein the data transmission includes a request for the UE to adjust a subsequent uplink transmission if one or both of the determined MCS or the determined TTI bundling size differ from respective values that the UE expected.