nal The CSI-RS physical signal (Channel State Information Reference Signal) is used to perform coherent demodulation of the received signal. The coherent demodulation of the received signal is based on the estimation of the transfer function of the radio channel. The CSI-RS physical signal allows the implementation of spatial multiplexing and transmission diversity. The strength of the CSI-RS physical signal is either transmitted to determine the level of the received signal or removed to measure the level of interference. The CSI-RS physical signal is used to measure the RSRP (Reference Signal Received Power) and the RSRQ (Reference Signal Received Quality). 6.2.1.2. The MBSFN-RS physical signal The MBSFN (MBMS Single Frequency Network) RS physical signal is transmitted only in the PMCH (Physical Multicast Channel) to perform coherent demodulation of the received signal. The PMCH physical channel is used to transmit IP (Internet Protocol) packets in broadcast mode. 6.2.1.3. The DM-RS physical signal The DM-RS physical signal is used for the beamforming mechanism and for spatial multiplexing of several users. The DM-RS signal is associated with a PDSCH (Physical Downlink Shared Channel), a PDCCH (Physical Downlink Control Channel) or a PBCH (Physical Broadcast Channel) to allow demodulation of the associated physical channel. The DM-RS physical signal allows the following configurations: - one user using a single spatial layer; - one user, using two spatial layers, and a beamforming associated with MIMO 2x2 spatial multiplexing; - two users, using two spatial layers, the multiplexing of the two users being carried out by an identity code; 174 NG-RAN and 5G-NR - four users, using a spatial layer, the multiplexing of the four spatial layers being obtained from an OCC (Orthogonal Covering Code) and an identity code; - a user using eight spatial layers, and a beamforming associated with 8x8 MIMO spatial multiplexing. 6.2.1.4. The PRS physical signal The PRS (Positioning Reference Signal) physical signal is used by th