 precoding matrix and informs the device through uplink sched- uling grant. At the UE side, the precoding matrix is applied to the scheduled PUSCH trans- mission and the indicated number of layers is mapped to the antenna ports. To select a suitable rank and a corresponding precoding matrix, the gNB needs estimates of the chan- nels between the device antenna ports and the corresponding network receive antennas. To enable this, a UE configured for codebook-based PUSCH transmission would typically be configured for transmission of at least one multi-port SRS. Based on measurements on the configured SRS, the network can estimate the channel and determine a suitable rank and precoding matrix. The network cannot select an arbitrary precoder, rather for a given combi- nation of the antenna ports and transmission rank, the network can select the precoding matrix from a limited set of available precoders [6,9,14]. When selecting the precoding matrix, the network needs to consider the device capability in terms of antenna-port phase coherence. If the UE does not support antenna-port phase coherence, only the first two precoding matrices can be used with rank-1 transmission. It must be noted that restricting the codebook selection to these two matrices is equivalent to selecting either the first or the second antenna port for transmission. In this type of antenna selection, phase coherence between the antenna ports is not required. The selec- tion of the remaining precoding vectors would imply linear combination of the signals of different antenna ports, which requires phase coherency among the antenna ports. A fun- damental difference between NR codebook-based PUSCH transmission and LTE uplink is that a device can be configured to transmit multiple SRS from multiple antenna ports. In multi-SRS transmission, the network feedback includes SRI, identifying one of the config- ured SRSs. The UE should then use the precoder identified in the scheduling grant and map the output of the precoder to the antenna ports corresponding