Patent ID: 11902198
Assignee: GOOGLE LLC
Field: Telecommunications (Electrical engineering)
Classification: CPC H | IPC H

Claim 0:
1. A method in a base station for controlling transmissions to a user equipment (UE) over a downlink (DL) multiple-input, multiple-output (MIMO) channel, the method comprising:
determining that the UE is configured to support N DL MIMO layers and transmit reference signals over L antenna chains;
receiving L uplink reference signals, each transmitted by the UE over a respective one of the L antenna chains;
receiving, from the UE, one or more additional transmissions including a hybrid automatic repeat request (HARQ) message or a scheduling request;
in response to determining that L<N, generating channel information for the DL MIMO channel using (i) the L uplink reference signals and (ii) the one or more additional transmissions received from the UE; and
transmitting a plurality of data streams over the DL MIMO channel in accordance with the generated channel information.