of the allocation of the other modem and then decide the A-MPR based on a formula defined in TS 38.101-3. As mentioned in Section 12.5.3, the network is responsible for ensuring that the non-DPS UE does not exceed Pcmax. Hence, in addition to the A-MPR that the UE calculates, the network can configure single switched uplink operation or cap the LTE and NR transmission powers to a certain limit, for example, to +20 dBm by signaling p-MaxEUTRA and p-NR-FR1, respectively. 12.5.4.2 Inter-Band Challenges Inter-band EN-DC is far more popular in the Release 15 specifications than intra-band EN-DC, and all kinds of EN-DC band combinations have been specified. The most com- plex combination comprises five LTE bands and one FR1 5G band. Furthermore, band combinations involving LTE together with FR2 5G or LTE together with FR1 and FR2 5G are specified. How the UE treats MPR/A-MPR is a bit simpler for inter-band EN-DC compared to intra-band EN-DC. No matter whether the UE supports or does not support DPS, 12 5G RF Design Challenges both LTE and 5G modems follow single-carrier MPR/A-MPR definitions as defined in 36.101 and 38.101-1 for LTE and 5G, respectively. If the UE does support DPS, then the network is ultimately responsible for ensuring that the UE does not exceed PCmax. If the UE supports DPS, then the NR modem ensures that PCmax is not exceeded, as explained in the previous paragraph. Intra- and inter-band EN-DC configurations are illustrated in Figure 12.18 using the following examples, where MSD results from the presence of IMD products due to simultaneous uplink transmissions: Large MSDs may occur for FDD intra-band contiguous configurations in bands with short distance duplex as shown in Figure 12.18a. For example, in rel-15 DC_(n)71AA NR PCC, MSD due to IMD 7 can be as high as 30 dB and LTE MSD due to IMD9 as high as 17 dB (cf. Section 12.5.4.3). Note that despite these large MSDs, this configu- ration is not eligible for SUO operation. Large MSDs may also occur in the case of inter-band configurations such as D