 PDSCH physical channel and received at the SSB block: - the CQI (Channel Quality Indicator) information corresponds to the modulation and coding scheme recommended for the PDSCH physical channel; - the RI (Rank Indicator) information determines the number of spatial layers recommended for the PDSCH physical channel; - the PMI (Precoder Matrix Indicator) information provides indications relating to the precoding matrix in the case of use of spatial multiplexing, in closed loop, or in the case of beamforming. The reporting of CSI can be periodic or aperiodic: The aperiodic report is always transferred to the PUSCH (Physical Uplink Shared Channel) physical channel. 176 NG-RAN and 5G-NR The periodic report is transferred to the PUCCH (Physical Uplink Control Channel) in the following two cases: - no resource is allocated to the mobile in the PUSCH physical channel; - a resource is allocated to the mobile, and simultaneous transmission of the PUCCH and PUSCH physical channels is possible. Otherwise, the periodic report is transmitted in the PUSCH physical channel. The report transfer modes are built according to the type of feedback from the CQI and PMI information. The type of transfer of the aperiodic or periodic report and the types of measurements are communicated to the mobile by the RRC Setup or RRC Reconfiguration messages. The aperiodic report is used to report CSI relating to the BWP (Bandwidth Partition) of the radio channel or to sub-bands of the radio channel, depending on the format indicator cqi-FormatIndicator. The transfer of the aperiodic report is triggered by the following messages: - DCI (Downlink Control Information) transmitted in the PDCCH (Physical Downlink Control Channel); - the RAR (Random Access Response) message transmitted in the PDSCH. 6.4. PDSCH transmission 6.4.1. Single-CSI and multiple-CSI transmission Whereas 10 transmission modes (TM) have been defined for 4G, there is only one transmission mode in Release R.16 for the PDSCH. Nevertheless, this transmission mode makes it possible 