time space, and a set of contiguous subcarriers in the frequency domain ( The resource grid consists of a maximum of 3,300 subcarriers and is transmitted on each direction of transmission and on each antenna port. Number of symbols Number of slots Number of symbols per Numerology in a slot per subframe subframe Table 4.6. The structure of the resource grid in the temporal domain 100 NG-RAN and 5G-NR The starting position of the resource grid N start,, grid and the spectral width NSize, grid are transmitted by the RRC message in the case of 5G-NSA, or via the SIB1 message in the case of 5G-SA. 4.3.2. Resource bloc and bandwidth part Two types of resource block are defined: - a physical resource block (PRB); - a common resource block (CRB). As the resource grid is characterized by its numerology and the number of contiguous PRB resource blocks, it is necessary to define the position of the resource grid N grid start,, from the number of the CRB. The first resource block of the 5G-NR band is located in the frequency domain by a reference point, named point A. The reference point is identified as being the common resource block 0. The location of point A is transmitted to the mobile by either: - an offset between the synchronization signal and the start of the 5G band by the offset value OffsetToPointA; - or an absolute reference AbsoluteFrequencyPointA, indicating the frequency number ARFCN (Absolute Radio Frequency Channel Number) separating the synchronization signal to the reference point A. In the case of 5G-NSA, only the absolute reference is transmitted to the mobile in an RRC ConnectionReconfiguration message. In the case of 5G-SA, the mobile retrieves this value from the information message SIB1. The reference point (Point A) is the starting point for the numbering of the common resource blocks. The position of the CRBs is defined from this point according to their numerology. For a given numerology , if k is the number of subcarriers separating a resource block from point A, then the number of the common re