US 11,888,555 B2
Method to beamform multicast transmission
Ratheesh Kumar Mungara, Sundbyberg (SE); Sairamesh Nammi, Kista (SE); and Jörg Huschke, Cologne (DE)
Assigned to Telefonaktiebolaget LM Ericsson (Publ), Stockholm (SE)
Appl. No. 17/784,828
Filed by Telefonaktiebolaget LM Ericsson (publ), Stockholm (SE)
PCT Filed Dec. 11, 2020, PCT No. PCT/EP2020/085854
§ 371(c)(1), (2) Date Jun. 13, 2022,
PCT Pub. No. WO2021/116461, PCT Pub. Date Jun. 17, 2021.
Claims priority of provisional application 62/948,012, filed on Dec. 13, 2019.
Prior Publication US 2023/0010083 A1, Jan. 12, 2023
Int. Cl. H04B 7/0456 (2017.01)
CPC H04B 7/0456 (2013.01) 25 Claims
OG exemplary drawing
 
1. A method performed by a network node, the method comprising:
receiving channel state information, CSI, from each of a plurality of wireless devices;
determining at least one null space based on the received CSI from each of the plurality of wireless devices;
determining a common precoding matrix index, PMI, the common PMI comprising a common beamforming vector which is not in the at least one null space of any one of individual beamforming vectors of the plurality of wireless devices; and
causing a multicast broadcast transmission to the plurality of wireless devices using at least the common PMI.