Controlling multiplexing of a reference signal on an uplink shared channel
Methods, systems, and devices for wireless communications are described for controlling multiplexing of a reference signal on an uplink shared channel (UL-SCH). In an implementation, a user equipment (UE) may time division multiplex (TDM) a demodulation reference signal (DMRS) with other signaling across symbol periods of one or more allocated resource blocks. The UE may map the DMRS to resource elements of one or more symbol periods within the allocated resource blocks. The UE may then map uplink control information (UCI) to one or more symbol periods different than the symbol periods of the DMRS mapping. In some cases, the DMRS, UCI, or both may be frequency interleaved with UL-SCH data for the allocated resource blocks. The UE may generate and transmit an uplink waveform for transmission within the allocated resources of the uplink shared channel.
1. A user equipment (UE) for wireless communication, comprising:
memory storing processor-executable code; and
one or more processors coupled with the memory and operable to execute the code to cause the UE to:
receive, by the UE, downlink control information comprising a grant allocating a resource block of an uplink shared channel for an uplink transmission and indicating whether to frequency division multiplex a demodulation reference signal with uplink shared data based at least in part on whether the uplink transmission comprises the uplink shared data;
determine, by the UE, a mapping for the resource block of the uplink shared channel that includes the demodulation reference signal and uplink control information in the resource block of the uplink shared channel, wherein the demodulation reference signal is mapped to two symbols periods of the uplink shared channel and resource elements of the demodulation reference signal in each symbol period are separated by one or more intervening resource elements, and wherein, to determine the mapping, the one or more processors are further operable to execute the code to cause the UE to:
time division multiplex the demodulation reference signal and the uplink control information to different symbol periods of the resource block of the uplink shared channel, wherein:
the demodulation reference signal and the uplink shared data are frequency division multiplexed when the downlink control information indicates that the uplink transmission comprises the uplink shared data and the downlink control information indicates to frequency division multiplex the demodulation reference signal with the uplink shared data; or
the one or more intervening resource elements are empty when the downlink control information indicates that the uplink transmission does not comprise the uplink shared data; and
transmit the uplink transmission within the resource block of the uplink shared channel based at least in part on the mapping.
2. The UE of claim 1 , wherein, to transmit the uplink transmission, the one or more processors are operable to execute the code to cause the UE to:
transmit the demodulation reference signal on resource elements of a first symbol period of the resource block of the uplink shared channel and the uplink control information on resource elements of a second symbol period of the resource block of the uplink shared channel, the second symbol period distinct from the first symbol period.
3. The UE of claim 1 , wherein the one or more processors are further operable to execute the code to cause the UE to:
receive, by the UE, radio resource control signaling comprising a waveform indicator that indicates a type of an uplink waveform of the uplink transmission.
4. The UE of claim 1 , wherein the uplink control information comprises a hybrid automatic repeat request acknowledgement indication.
5. The UE of claim 1 , wherein the uplink control information comprises control state information part 1 data that includes at least one of a rank indicator, a channel state information reference signal index, or a channel quality indicator.
6. The UE of claim 1 , wherein the uplink control information comprises control state information part 2 data that includes at least one of a precoding matrix indicator, or a channel quality indicator.
7. A method for wireless communication by a user equipment (UE), comprising:
receiving, by the UE, downlink control information comprising a grant allocating a resource block of an uplink shared channel for an uplink transmission and indicating whether to frequency division multiplex a demodulation reference signal with uplink shared data based at least in part on whether the uplink transmission comprises the uplink shared data;
determining, by the UE, a mapping for the resource block of the uplink shared channel that includes the demodulation reference signal and uplink control information in the resource block of the uplink shared channel, wherein the demodulation reference signal is mapped in two symbols periods of the uplink shared channel and resource elements of the demodulation reference signal in each symbol period are separated by one or more intervening resource elements, and wherein the determining the mapping comprises:
time division multiplexing the demodulation reference signal and the uplink control information to different symbol periods of the resource block of the uplink shared channel, wherein:
the demodulation reference signal and the uplink shared data are frequency division multiplexed when the downlink control information indicates that the uplink transmission comprises the uplink shared data and the downlink control information indicates to frequency division multiplex the demodulation reference signal with the uplink shared data; or
the one or more intervening resource elements are empty when the downlink control information indicates that the uplink transmission does not comprise the uplink shared data; and
transmitting the uplink transmission within the resource block of the uplink shared channel based at least in part on the mapping.
8. The method of claim 7 , wherein transmitting the uplink transmission comprises:
transmitting the demodulation reference signal on resource elements of a first symbol period of the resource block of the uplink shared channel and the uplink control information on resource elements of a second symbol period of the resource block of the uplink shared channel, the second symbol period distinct from the first symbol period.
9. The method of claim 7 , further comprising:
receiving, by the UE, radio resource control signaling comprising a waveform indicator that indicates a type of an uplink waveform of the uplink transmission.
10. The method of claim 7 , wherein the uplink control information comprises a hybrid automatic repeat request acknowledgement indication.
11. The method of claim 7 , wherein the uplink control information comprises control state information part 1 data that includes at least one of a rank indicator, a channel state information reference signal index, or a channel quality indicator.
12. The method of claim 7 , wherein the uplink control information comprises control state information part 2 data that includes at least one of a precoding matrix indicator, or a channel quality indicator.
13. A user equipment (UE) for wireless communication, comprising:
means for receiving, by the UE, downlink control information comprising a grant allocating a resource block of an uplink shared channel for an uplink transmission and indicating whether to frequency division multiplex a demodulation reference signal with uplink shared data based at least in part on whether the uplink transmission comprises the uplink shared data;
means for determining, by the UE, a mapping for the resource block of the uplink shared channel that includes the demodulation reference signal and uplink control information in the resource block of the uplink shared channel, wherein the demodulation reference signal is mapped in two symbols periods of the uplink shared channel and resource elements of the demodulation reference signal in each symbol period are separated by one or more intervening resource elements, and wherein the means for determining the mapping comprises:
means for time division multiplexing the demodulation reference signal and the uplink control information to different symbol periods of the resource block of the uplink shared channel, wherein:
the demodulation reference signal and the uplink shared data are frequency division multiplexed when the downlink control information indicates that the uplink transmission comprises the uplink shared data and the downlink control information indicates to frequency division multiplex the demodulation reference signal with the uplink shared data; or
the one or more intervening resource elements are empty when the downlink control information indicates that the uplink transmission does not comprise the uplink shared data; and
means for transmitting the uplink transmission within the resource block of the uplink shared channel based at least in part on the mapping.
14. The UE of claim 13 , wherein the means for transmitting the uplink transmission comprise:
means for transmitting the demodulation reference signal on resource elements of a first symbol period of the resource block of the uplink shared channel and the uplink control information on resource elements of a second symbol period of the resource block of the uplink shared channel, the second symbol period distinct from the first symbol period.
15. The UE of claim 13 , further comprising:
means for receiving, by the UE, radio resource control signaling comprising a waveform indicator that indicates a type of an uplink waveform of the uplink transmission.
16. The UE of claim 13 , wherein the uplink control information comprises a hybrid automatic repeat request acknowledgement indication.
17. The UE of claim 13 , wherein the uplink control information comprises control state information part 1 data that includes at least one of a rank indicator, a channel state information reference signal index, or a channel quality indicator.
18. A non-transitory computer-readable medium storing code for wireless communication, the code comprising instructions executable by one or more processors to:
receive, by a user equipment (UE), downlink control information comprising a grant allocating a resource block of an uplink shared channel for an uplink transmission and indicating whether to frequency division multiplex a demodulation reference signal with uplink shared data based at least in part on whether the uplink transmission comprises the uplink shared data;
determine, by the UE, a mapping for the resource block of the uplink shared channel that includes the demodulation reference signal and uplink control information in the resource block of the uplink shared channel, wherein the demodulation reference signal is mapped in two symbols periods of the uplink shared channel and resource elements of the demodulation reference signal in each symbol period are separated by one or more intervening resource elements, and wherein, to determine the mapping, the one or more processors are further operable to execute the code to:
time division multiplexing the demodulation reference signal and the uplink control information to different symbol periods of the resource block of the uplink shared channel, wherein:
the demodulation reference signal and the uplink shared data are frequency division multiplexed when the downlink control information indicates that the uplink transmission comprises the uplink shared data and the downlink control information indicates to frequency division multiplex the demodulation reference signal with the uplink shared data; or
the one or more intervening resource elements are empty when the downlink control information indicates that the uplink transmission does not comprise the uplink shared data; and
transmit the uplink transmission within the resource block of the uplink shared channel based at least in part on the mapping.