Techniques for codebook and control signaling for uplink
Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may receive signaling identifying a transmission precoding matrix indicator associated with a transmit codebook configured for three antenna ports. The UE may transmit an uplink communication in accordance with the transmit codebook configured for three antenna ports. Numerous other aspects are described.
1 . A user equipment (UE) for wireless communication, comprising:
a memory; and
one or more processors, coupled to the memory, configured to:
receive signaling identifying a transmission precoding matrix indicator associated with a transmit codebook configured for three antenna ports, wherein the transmission precoding matrix indicator is associated with a multi-bit transmission precoding matrix indicator field included in an uplink grant, wherein the transmit codebook configured for the three antenna ports allows a plurality of different combinations of partial coherency of the three antenna ports; and
transmit an uplink communication in accordance with the transmit codebook configured for the three antenna ports, wherein the transmit codebook configured for the three antenna ports is based at least in part on an equation that comprises two Hermitian transposes of a Householder vector, wherein the equation is associated with a scaled version of a Householder matrix.
2 . The UE of claim 1 , wherein the one or more processors, to transmit the uplink communication, are configured to:
transmit the uplink communication using three or more radio frequency transmit chains, wherein a first radio frequency transmit chain and a second radio frequency transmit chain are coherent with each other, and wherein a third radio frequency transmit chain is non-coherent with the first radio frequency transmit chain and the second radio frequency transmit chain.
3 . The UE of claim 1 , wherein the transmit codebook configured for the three antenna ports is associated with cyclic-prefix orthogonal frequency division multiplexing of symbols of the uplink communication.
4 . The UE of claim 1 , wherein the transmission precoding matrix indicator is associated with a rank indication for the uplink communication.
5 . The UE of claim 1 , wherein the transmit codebook configured for the three antenna ports is associated with discrete Fourier transform spread orthogonal frequency division multiplexing of symbols of the uplink communication.
6 . The UE of claim 1 , wherein the transmit codebook configured for the three antenna ports is partially coherent.
7 . The UE of claim 1 , wherein the UE is configured with a port grouping and the transmit codebook configured for the three antenna ports is configured for the port grouping.
8 . The UE of claim 1 , wherein the UE is configured for coherence between two of the three antenna ports and is configured for non-coherence between the other antenna port of the three antenna ports.
9 . The UE of claim 1 , wherein wherein the uplink communication is transmitting using a plurality of radio frequency transmit chains, and wherein a first radio frequency transmit chain and a second radio frequency transmit chain are coherent with each other.
10 . The UE of claim 1 , wherein the equation comprises:
W
l
=
e
-
j
π
6
(
I
-
(
1
-
e
j
2
π
3
)
u
l
H
u
l
u
l
u
l
H
)
where W represents a precoding matrix, j represents a value of −1, I represents a 3×3 identity matrix, u represents the Householder vector, 1 represents a precoding matrix index, and H represents a Hermitian transpose.
11 . The UE of claim 1 , wherein the transmit codebook configured for the three antenna ports is based at least in part on a structured design configuration.
12 . The UE of claim 1 , wherein the UE is configured with a set of codebook subset restriction (CSR) configurations from which the transmit codebook configured for the three antenna ports is selected, the set of CSR configurations including:
a first CSR configuration for a non-coherent codebook,
a second CSR configuration for a partially coherent codebook, or
a third CSR configuration for a fully coherent codebook.
13 . The UE of claim 1 , wherein the UE is configured with a set of codebook subset restriction (CSR) configurations from which the transmit codebook configured for the three antenna ports is selected, the set of CSR configurations including:
a first CSR configuration for a non-coherent codebook,
a second CSR configuration for the non-coherent codebook and a partially coherent codebook, or
a third CSR configuration for the non-coherent codebook, the partially coherent codebook, and a fully coherent codebook.
14 . The UE of claim 1 , wherein the multi-bit transmission precoding matrix indicator field is associated with a mapping to a non-coherent codebook or a partially coherent codebook.
15 . The UE of claim 1 , wherein the transmit codebook configured for the three antenna ports is configured with 1, 3, 4, 6, 8, or 9 precoders based at least in part on a rank or type of coherency.
16 . The UE of claim 1 , wherein the transmission precoding matrix indicator is associated with a 2-bit rank indicator field and a 3-bit transmission precoding matrix indicator field associated with a mapping to a fully coherent codebook.
17 . The UE of claim 1 , wherein:
a first combination of the plurality of different combinations comprises a first antenna port of the three antenna ports and a second antenna port of the three antenna ports being coherent, and a third antenna port of the three antenna ports being non-coherent with the first antenna port and the second antenna port; and
a second combination of the plurality of different combinations comprises the second antenna port and the third antenna port being coherent, and the first antenna port being non-coherent with the second antenna port and the third antenna port.
18 . The UE of claim 1 , wherein the Householder vector is based at least in part on a transpose operation.
19 . A method of wireless communication performed by a user equipment (UE), comprising:
receiving signaling identifying a transmission precoding matrix indicator associated with a transmit codebook configured for three antenna ports, wherein the transmission precoding matrix indicator is associated with a multi-bit transmission precoding matrix indicator field included in an uplink grant, wherein the transmit codebook configured for the three antenna ports allows a plurality of different combinations of partial coherency of the three antenna ports; and
transmitting an uplink communication in accordance with the transmit codebook configured for the three antenna ports, wherein the transmit codebook configured for the three antenna ports is based at least in part on an equation that comprises two Hermitian transposes of a Householder vector, wherein the equation is associated with a scaled version of a Householder matrix.
20 . A non-transitory computer-readable medium storing a set of instructions for wireless communication, the set of instructions comprising:
one or more instructions that, when executed by one or more processors of a user equipment (UE), cause the UE to:
receive signaling identifying a transmission precoding matrix indicator associated with a transmit codebook configured for three antenna ports, wherein the transmission precoding matrix indicator is associated with a multi-bit transmission precoding matrix indicator field included in an uplink grant, wherein the transmit codebook configured for the three antenna ports allows a plurality of different combinations of partial coherency of the three antenna ports; and
transmit an uplink communication in accordance with the transmit codebook configured for the three antenna ports, wherein the transmit codebook configured for the three antenna ports is based at least in part on an equation that comprises two Hermitian transposes of a Householder vector, wherein the equation is associated with a scaled version of a Householder matrix.