ency Frequency Band Subcarrier Component Carrier Bandwidth (MHz) Range Frequency Spacing Number (kHz) (GHz) n257/ 24-40 n260/ 660 Chapter 5 BW channel- channel bandwidth (MHz) Guard band Transmission bandwidth configuration NRB [RB] Guard band Transmission bandwidth [RB] Spectrum Resource block Active resource blocks Note: guard bands can be asymmetric. emission mask Figure 5.2 Illustration of channel bandwidth, transmission bandwidth, and guard bands [5]. The channel bandwidth of a gNB (BW channel) supports transmission on a single (NR) uplink or downlink RF carrier. Different UE channel bandwidths may be supported within the same gNB channel bandwidth for bidirectional communication with the UE. The relative location of the UE channel bandwidth is flexible and within the gNB channel bandwidth. The gNB is able to transmit/receive to/from one or more UE bandwidth parts that are smal- ler than or equal to the total number of carrier resource blocks on the RF carrier. The rela- tionship between the channel bandwidth, guard band, and the transmission bandwidth is shown in Fig. 5.2. The transmission bandwidth configuration in terms of the number of physical resource blocks (NRB) for each BS channel bandwidth and SCS was given in Table 3.9, for FR1 and FR2. The minimum guard band for each BS channel bandwidth and SCS is shown in Table 5.2 for FR1 and FR2. The minimum guard band shown for SCS of 240 kHz is only applicable when an SS/PBCH block (SSB) with SCS of 240 kHz is placed adjacent to the edge of the BS channel bandwidth within which the SSB is located; other- wise, 240 kHz subcarrier spacing is not used for any other configurations. The number of RBs configured within any BS channel bandwidth will guarantee that the minimum guard band shown in Table 5.2 is satisfied. If multiple numerologies are multiplexed over the same OFDM symbol, the minimum guard band on each side of the carrier is the guard band applied at the configured BS channel bandwidth for the numerology that is transmitted/received adjacent to the g