Cooperation with digital frequency-translation repeater for uplink transmission and reception-base station behavior
In an aspect of the disclosure, a method, a computer-readable medium, and an apparatus are provided. The apparatus may be a base station. The base station receives baseband signals from X devices at N R reception antennas. These baseband signals carry R layers of data signals transmitted from a UE using N T transmission antennas in L first transmission time intervals, where L, N R and R are positive integers. The base station estimates an equivalent channel response that is formed by precoders used by the UE and a channel between the N R reception antennas at the base station and L·N T effective antennas at the UE; N T is a positive integer. The base station performs signal processing based on the received baseband signals and the channel response in order to decode the R layers of data signals from the UE.
1 . A method of wireless communication of a base station, comprising:
receiving, from X devices, baseband signals at N R reception antennas of the base station, wherein the baseband signals carry R layers of data signals transmitted from a UE using N T transmission antennas in L first transmission time intervals corresponding to a first subcarrier spacing, X, L, N R and R being positive integers;
estimating an equivalent channel response formed by precoders used by the UE and a channel between the N R reception antennas at the base station and L·N T effective antennas at the UE, N T being a positive integer; and
performing signal processing based on the received baseband signals and the channel response to decode the R layers of data signals from the UE.
2 . The method of claim 1 , further comprising:
obtaining a first mapping that maps a first set of N 1 data signals carried on a first set of N 1 subcarriers transmitted by the UE to a second set of N 2 data signals carried on a second set of N 2 subcarriers transmitted by each of the X devices, N 2 being positive an integer, wherein the signal processing is performed further based on the first mapping.
3 . The method of claim 1 , further comprising:
determining that R precoders are used by the UE to precode the R layers of data signals to the N T transmission antennas in subsets or all of the L first transmission time intervals, respectively, L being further equal to or greater than the value of X, wherein the baseband signals are received in a second transmission time interval corresponding to a second subcarrier spacing, wherein the second transmission time interval is equal to or greater than the L first transmission time intervals.
4 . The method of claim 3 , wherein the R precoders are determined by the base-station and are signaled to the UE.
5 . The method of claim 3 , wherein each of the R precoders is used by the UE to precode each of the R layers of data signals to the N T transmission antennas in all of the L first transmission time intervals.
6 . The method of claim 3 , wherein each of the R precoders is used by the UE to precode each of the R layers of data signals to the N T transmission antennas in subsets of the L first transmission time intervals.
7 . The method of claim 3 , wherein the R precoders are determined based on channel state information obtained from the UE or the base station.
8 . The method of claim 1 , further comprising:
transmitting control information to the UE, the control information including at least one of: (a) available time-frequency resources for UE transmission and (b) a transmission control information state or spatial relation for a transmission beam used in each first transmission time interval.
9 . The method of claim 1 , further comprising:
transmitting control information, the control information including parameters for the X devices to receive radio frequency (RF) signals on a first frequency carrying the R layers of data signals from the UE and to transmit RF signals on a second frequency carrying the R layers to the base station.
10 . The method of claim 9 , wherein the control information includes at least one of: (a) frequency band parameters for the first and second frequencies, (b) associated channel bandwidths and subcarrier spacings in the first and second frequencies, (c) a transmission control information state or spatial relation for a reception beam used in each first transmission time interval, (d) fast Fourier transform (FFT) and inverse FFT sizes, and (e) a first mapping that maps a first set of N 1 data signals carried on a first set of N 1 subcarriers transmitted by the UE to a second set of N 2 data signals carried on a second set of N 2 subcarriers transmitted by each of the X devices.
11 . An apparatus for wireless communication, the apparatus being a base station, comprising:
a memory; and
at least one processor coupled to the memory and configured to:
receive, from X devices, baseband signals at N R reception antennas of the base station, wherein the baseband signals carry R layers of data signals transmitted from a UE using N T transmission antennas in L first transmission time intervals corresponding to a first subcarrier spacing, X, L, N R and R being positive integers;
estimate an equivalent channel response formed by precoders used by the UE and a channel between the N R reception antennas at the base station and L·N T effective antennas at the UE, N being a positive integer; and
perform signal processing based on the received baseband signals and the channel response to decode the R layers of data signals from the UE.
12 . The apparatus of claim 11 , wherein the at least one processor is further configured to:
obtain a first mapping that maps a first set of N 1 data signals carried on a first set of N 1 subcarriers transmitted by the UE to a second set of N 2 data signals carried on a second set of N 2 subcarriers transmitted by each of the X devices, N 2 being positive an integer, wherein the signal processing is performed further based on the first mapping.
13 . The apparatus of claim 11 , wherein the at least one processor is further configured to:
determine that R precoders are used by the UE to precode the R layers of data signals to the N T transmission antennas in subsets or all of the L first transmission time intervals, respectively, L being further equal to or greater than the value of X, wherein the baseband signals are received in a second transmission time interval corresponding to a second subcarrier spacing, wherein the second transmission time interval is equal to or greater than the L first transmission time intervals.
14 . The apparatus of claim 13 , wherein the R precoders are determined by the base-station and are signaled to the UE.
15 . The apparatus of claim 13 , wherein each of the R precoders is used by the UE to precode each of the R layers of data signals to the N T transmission antennas in all of the L first transmission time intervals.
16 . The apparatus of claim 13 , wherein each of the R precoders is used by the UE to precode each of the R layers of data signals to the N transmission antennas in subsets of the L first transmission time intervals.
17 . The apparatus of claim 13 , wherein the R precoders are determined based on channel state information obtained from the UE or the base station.
18 . The apparatus of claim 11 , wherein the at least one processor is further configured to:
transmit control information to the UE, the control information including at least one of: (a) available time-frequency resources for UE transmission and (b) a transmission control information state or spatial relation for a transmission beam used in each first transmission time interval.
19 . The apparatus of claim 11 , wherein the at least one processor is further configured to:
transmit control information, the control information including parameters for the X devices to receive radio frequency (RF) signals on a first frequency carrying the R layers of data signals from the UE and to transmit RF signals on a second frequency carrying the R layers to the base station.
20 . A non-transitory computer-readable medium storing computer executable code for wireless communication of a base station, comprising code to:
receive, from X devices, baseband signals at N R reception antennas of the base station, wherein the baseband signals carry R layers of data signals transmitted from a UE using N T transmission antennas in L first transmission time intervals corresponding to a first subcarrier spacing, X, L, N R and R being positive integers;
estimate an equivalent channel response formed by precoders used by the UE and a channel between the N R reception antennas at the base station and L·N T effective antennas at the UE, N T being a positive integer; and
perform signal processing based on the received baseband signals and the channel response to decode the R layers of data signals from the UE.