Reply To: 8Tx Codebook nt.tuwien.ac.at > Reply To: 8Tx Codebook Search for: 12. March 2017 at 10:51 #7722 Stefan SchwarzParticipant Dear Yang, PMI_WB stands for wideband precoding matrix indicator. It is essentially the sam as the codebook_index. For 8 antennas, the codebook is indexed by two indices the subband PMI and the wideband PMI. Regards Stefan.