Dual port SSB for multi-Rx beam selection
Techniques described herein include solutions for utilizing dual port synchronization signal block (SSB) transmissions for multiple receive (Rx) beam selection. In some aspects, a base station transmits a first SSB with a first polarization on a first antenna port, and transmits a second SSB with a second polarization on a second antenna port. The first and second SSBs may be transmitted, for example, using a first transmission reception point (TRP). A user equipment (UE) receives the first and second SSBs, and identifies one or more optimal Rx beams for multiple-input multiple-output (MIMO) communication based on the first and second SSBs.
1 . A baseband processor for a user equipment (UE), the baseband processor configured to, when executing instructions stored in a memory, perform operations comprising:
receiving, from a first transmission reception point (TRP), a first synchronization signal block (SSB) with a first polarization and a second SSB with a second polarization different than the first polarization;
receiving, from a second TRP, a third SSB with a third polarization and a fourth SSB with a fourth polarization different than the third polarization;
identifying one or more optimal receive (Rx) beams for multiple-input multiple-output (MIMO) communication, based on the first SSB, the second SSB, the third SSB, and the fourth SSB; and
receiving a MIMO transmission using the one or more optimal Rx beams.
2 . The baseband processor of claim 1 , wherein the operations further comprise receiving the first SSB and the second SSB using a same set of frequency resources.
3 . The baseband processor of claim 1 , wherein the first polarization and the second polarization are approximately orthogonal.
4 . The baseband processor of claim 1 , wherein the first TRP and the second TRP are part of a same base station.
5 . The baseband processor of claim 1 , wherein the operations further comprise receiving the first, second, third, and fourth SSBs using at least two antenna panels.
6 . The baseband processor of claim 1 , wherein the operations further comprise receiving the first, second, third, and fourth SSBs using at least four antenna ports.
7 . The baseband processor of claim 1 , wherein the operations further comprise:
determining a channel matrix based on the first SSB and the second SSB; and
identifying the one or more optimal Rx beams based on the channel matrix using a linear minimum mean square error (LMMSE) criterion.
8 . The baseband processor of claim 7 , wherein the operations further comprise identifying the one or more optimal Rx beams from a codebook of Rx beams.
9 . A method for a user equipment (UE), comprising:
receiving, from a first transmission reception point (TRP), a first synchronization signal block (SSB) with a first polarization and a second SSB with a second polarization different than the first polarization;
determining a channel matrix based on the first SSB and the second SSB;
identifying, based on the channel matrix and a linear minimum mean square error (LMMSE) criterion, one or more optimal receive (Rx) beams for multiple-input multiple-output (MIMO) communication; and
receiving data using the one or more optimal Rx beams.
10 . The method of claim 9 , further comprising receiving the first SSB and the second SSB using a same set of frequency resources.
11 . The method of claim 9 , wherein the first polarization and the second polarization are approximately orthogonal.
12 . The method of claim 9 , further comprising receiving, from a second TRP, a third SSB with a third polarization and a fourth SSB with a fourth polarization, wherein the third polarization is different than the fourth polarization, and wherein identifying the one or more optimal Rx beams is further based on the third SSB and the fourth SSB.
13 . The baseband processor of claim 1 , wherein the operations further comprise:
estimating a channel matrix to determine the one or more optimal Rx beams, based on the first SSB, the second SSB, the third SSB, and the fourth SSB.
14 . The baseband processor of claim 1 , wherein the one or more optimal Rx beams are selected from a beam codebook.
15 . The baseband processor of claim 14 , wherein the beam codebook comprises M number of entries, and wherein the operations further comprise receiving M number of occasions of each of: the first SSB, the second SSB, the third SSB, and the fourth SSB, in order to identify the one or more optimal Rx beams.
16 . A user equipment (UE), comprising:
radio frequency (RF) circuitry; and
a processor coupled to the RF circuitry and configured to execute instructions stored in a memory to cause the UE to:
receive, from a first transmission reception point (TRP), a first synchronization signal block (SSB) with a first polarization and a second SSB with a second polarization different than the first polarization;
receive, from a second TRP, a third SSB with a third polarization and a fourth SSB with a fourth polarization different than the third polarization;
identify one or more optimal receive (Rx) beams for multiple-input multiple-output (MIMO) communication, based on the first SSB, the second SSB, the third SSB, and the fourth SSB; and
receive a MIMO transmission using the one or more optimal Rx beams.
17 . The UE of claim 16 , wherein the processor further causes the UE to receive the first SSB and the second SSB using a same set of frequency resources.
18 . The UE of claim 16 , wherein the first polarization and the second polarization are approximately orthogonal.
19 . The UE of claim 16 , wherein the first TRP and the second TRP are part of a same base station.
20 . The UE of claim 16 , wherein the processor further causes the UE to receive the first, second, third, and fourth SSBs using at least two antenna panels.