Uplink pre-coding based wireless communications
An apparatus for wireless communication includes a memory and one or more processors coupled to the memory. The one or more processors are configured to determine a plurality of pre-coders available for uplink transmissions and to select a particular pre-coder from among the plurality of pre-coders. The one or more processors are further configured to initiate encoding of an uplink signal based on the particular pre-coder to generate a pre-coded uplink signal. The pre-coded uplink signal has one or more characteristics that enable a base station to identify the particular pre-coder. The one or more processors are further configured to initiate transmission of the pre-coded uplink signal.
1. An apparatus for wireless communication, the apparatus comprising:
one or more processors;
memory coupled with the one or more processors; and
instructions stored in the memory and executable by the one or more processors, individually or collectively, to cause the apparatus to:
select a particular pre-coder from among a plurality of pre-coders;
initiate encoding of an uplink signal in accordance with the particular pre-coder to generate a pre-coded uplink signal, wherein the pre-coded uplink signal has one or more characteristics that enable a network node to identify the particular pre-coder; and
initiate transmission of the pre-coded uplink signal, wherein the one or more characteristics include one or more of a transmit power level associated with the encoded uplink signal, a transmit antenna associated with the encoded uplink signal, or a transmit port associated with the encoded uplink signal.
2. The apparatus of claim 1 , wherein the one or more characteristics implicitly indicate the particular pre-coder to the network node without use of an explicit indication of the particular pre-coder.
3. The apparatus of claim 1 , further comprising a plurality of ports configured to transmit the pre-coded uplink signal, wherein the plurality of ports include the transmit port, and wherein the one or more characteristics include a mapping of a plurality of power levels including the transmit power level to the plurality of ports.
4. The apparatus of claim 1 , wherein the one or more processors are further configured to determine the plurality of pre-coders in accordance with a message received from the network node and indicating the plurality of pre-coders.
5. The apparatus of claim 4 , wherein the message corresponds to a radio resource control (RRC) configuration message.
6. The apparatus of claim 4 , wherein the message corresponds to a medium access control (MAC) control element (MAC-CE) activation message.
7. The apparatus of claim 1 , wherein the one or more processors are further configured to initiate transmission, to the network node, of an indication of the plurality of pre-coders.
8. The apparatus of claim 7 , wherein the indication is included in a medium access control (MAC) control element (MAC-CE) report message.
9. The apparatus of claim 1 , further comprising a receiver configured to receive a channel state information (CSI) reference signal (CSI-RS) from the network node, wherein the one or more processors are further configured to select the particular pre-coder from among the plurality of pre-coders in accordance with the CSI-RS.
10. The apparatus of claim 1 , further comprising:
a plurality of ports including the transmit port; and
transmit circuitry configured to apply a first power level to a first port of the plurality of ports in accordance with a first bit value of the particular pre-coder and to apply a second power level to a second port of the plurality of ports in accordance with a second bit of the particular pre-coder, wherein the transmit power level corresponds to one of the first power level or the second power level, and wherein the transmit port corresponds to one of the first port or the second port.
11. The apparatus of claim 1 , wherein the pre-coded uplink signal corresponds to a sounding reference signal (SRS).
12. The apparatus of claim 1 , wherein the pre-coded uplink signal corresponds to a physical uplink shared channel (PUSCH) signal.
13. The apparatus of claim 1 , further comprising:
a plurality of antennas including the transmit antenna; and
a transmitter coupled to the plurality of antennas and configured to transmit the pre-coded uplink signal using a subset of the plurality of antennas, wherein the one or more characteristics enable the network node to identify the particular pre-coder in connection with transmission of the pre-coded uplink signal using the subset of the plurality of antennas.
14. A method of wireless communication performed by a user equipment (UE), the method comprising:
selecting a particular pre-coder from among a plurality of pre-coders;
encoding an uplink signal in accordance with the particular pre-coder to generate a pre-coded uplink signal, wherein the pre-coded uplink signal has one or more characteristics that enable a network node to identify the particular pre-coder; and
transmitting the pre-coded uplink signal, wherein the one or more characteristics include one or more of a transmit power level associated with the encoded uplink signal, a transmit antenna associated with the encoded uplink signal, or a transmit port associated with the encoded uplink signal.
15. The method of claim 14 , wherein the one or more characteristics implicitly indicate the particular pre-coder to the network node without use of an explicit indication of the particular pre-coder.
16. The method of claim 14 , wherein the pre-coded uplink signal is transmitted via a plurality of ports of the UE, wherein the plurality of ports include the transmit port, and wherein the one or more characteristics include a mapping of a plurality of power levels including the transmit power level to the plurality of ports of the UE.
17. The method of claim 14 , further comprising receiving, from the network node, a message indicating a quantity of consecutive physical resource blocks (PRBs) of the uplink signal to which particular pre-coder is to be applied, wherein the uplink signal is encoded further in accordance with the quantity.
18. The method of claim 14 , wherein the one or more characteristics include one or more of a plurality of transmit power levels associated with the encoded uplink signal and including the transmit power level, a plurality of transmit antennas associated with the encoded uplink signal and including the transmit antenna, or a plurality of transmit ports associated with the encoded uplink signal and including the transmit port.
19. An apparatus for wireless communication, the apparatus comprising:
one or more processors;
memory coupled with the one or more processors; and
instructions stored in the memory and executable by the one or more processors, individually or collectively, to cause the apparatus to:
receive, from a user equipment (UE), a pre-coded uplink signal;
in accordance with one or more characteristics of the pre-coded uplink signal, identify, from a plurality of pre-coders associated with uplink transmissions, a particular pre-coder used to generate the pre-coded uplink signal, wherein the one or more characteristics include one or more of a transmit power level associated with the encoded uplink signal, a transmit antenna associated with the encoded uplink signal, or a transmit port associated with the encoded uplink signal; and
in accordance with the particular pre-coder, initiate decoding of the pre-coded uplink signal.
20. The apparatus of claim 19 , wherein the one or more characteristics implicitly indicate the particular pre-coder without use of an explicit indication of the particular pre-coder.
21. The apparatus of claim 19 , wherein the pre-coded uplink signal is transmitted via a plurality of ports of the UE, wherein the plurality of ports include the transmit port, and wherein the one or more characteristics include a mapping of a plurality of power levels including the transmit power level to the plurality of ports of the UE.
22. The apparatus of claim 19 , further comprising a transmitter configured to transmit, to the UE, a message indicating the plurality of pre-coders.
23. The apparatus of claim 19 , further comprising a receiver configured to receive, from the UE, an indication of the plurality of pre-coders.
24. The apparatus of claim 19 , further comprising a transmitter configured to transmit a channel state information (CSI) reference signal (CSI-RS) to the UE, wherein the UE selects the particular pre-coder from among the plurality of pre-coders in accordance with the CSI-RS.
25. The apparatus of claim 19 , wherein the pre-coded uplink signal corresponds to a sounding reference signal (SRS).
26. The apparatus of claim 19 , wherein the pre-coded uplink signal corresponds to a physical uplink shared channel (PUSCH) signal.
27. The apparatus of claim 19 , wherein the UE includes a plurality of antennas including the transmit antenna, wherein the pre-coded uplink signal is transmitted using a subset of the plurality of antennas, and wherein the one or more characteristics enable identification of the particular pre-coder in connection with transmission of the pre-coded uplink signal using the subset of the plurality of antennas.
28. A method of wireless communication performed by a network node, the method comprising:
receiving, from a user equipment (UE), a pre-coded uplink signal;
in accordance with one or more characteristics of the pre-coded uplink signal, identifying, from a plurality of pre-coders associated with uplink transmissions, a particular pre-coder used to generate the pre-coded uplink signal, wherein the one or more characteristics include one or more of a transmit power level associated with the encoded uplink signal, a transmit antenna associated with the encoded uplink signal, or a transmit port associated with the encoded uplink signal; and
in accordance with the particular pre-coder, decoding the pre-coded uplink signal.
29. The method of claim 28 , wherein the one or more characteristics implicitly indicate the particular pre-coder to the network node without use of an explicit indication of the particular pre-coder, wherein the pre-coded uplink signal is transmitted via a plurality of ports of the UE, wherein the plurality of ports include the transmit port and wherein the one or more characteristics include a mapping of a plurality of power levels including the transmit power level to the plurality of ports of the UE.