source block is defined by: NCRB = M 5G-NR Radio Interface - The Physical Layer The BWP is a collection of contiguous block resources in a resource grid. An 1th BWP band partitioning is defined by its numerology and by its bandwidth. The bandwidth corresponds to the number of block resources N BWP,i The position of the physical resource blocks (PRB) inside the BWP varies from 0 at the start of the partition to NBWP.i-1. size A mobile can be configured to support, at most, four BWP partitions per carrier, but only one partition is active in the uplink and downlink directions (the limitation of four BWP concerns the specifications of Releases R. 15 and R.16, at least). The BWP makes it possible to adapt the 5G band to the capacities of the mobile. The mobile can only receive traffic data or control information inside the active BWP partition. Band NR Point A CRB numerology 0 SCS= 15 kHz SCS= 30 kHz PRB=0 PRB=N-3 BWP u=1 CRB=1 PRB=0 PRB=M-4 BWP u=0 CRB=3 Figure 4.6. Common resource block and physical resource block 4.4. Physical channels and physical signals 4.4.1. Physical signals and reference signals The physical PSS (Primary Synchronization Signal) ensures the synchronization of the OFDM signal and the time synchronization at the half-frame level. The physical SSS (Secondary Synchronization Signal) provides time synchronization at the frame level. The physical CSI-RS (Channel State Information RS) is a reference signal transmitted by the radio node gNB. The physical signal CSI-RS is specific to UE. It NG-RAN and 5G-NR aims for UE to perform a coherent demodulation of the received signal. Channel equalization is based on the calculation of the transfer function from CSI-RS. The physical SRS (Sound Reference Signal) is a mobile-specific reference signal, allowing the radio node gNB to perform a coherent demodulation of the received signal based on the calculation of the radio channel transfer function. The physical DM-RS (Demodulation RS) is a mobile-specific signal used to perform a coherent demodulation of the r