BTS processing delay MSG4: RRC setup UE processing delay MSG5: RRC setup complete BTS processing delay MME processing delay BTS processing delay Security mode command UE processing delay Total MSG, message; MME, Mobility Management Entity. 10.5 Link Budgets Figure 10.19 5G leg setup time measurement in non-standalone architecture. Attach complete in LTE 35 ms Secondary gNodeB setup complete 35 ms UE reconfiguration complete MME response to split bearer An example measurement is shown in Figure 10.19. The setup time in this case is below 100 ms. If the UE must first make measurements to find out the 5G signal levels, the setup time will be higher. Link Budgets 10.5.1 Link Budget for Sub-6-GHz TDD The 5G link budget is an important tool for estimating the coverage areas of 5G cells. We illustrate here the main factors impacting the maximum path loss values for different physical channels. The path loss can be converted to the cell range with propagation models like Okumura-Hata. We use the following assumptions: The base station antenna structure has a major impact on the link budget. Massive MIMO with beamforming gain can improve the link budget considerably. A 3.5 GHz three-sector beamforming antenna can provide a gain of 25 dBi. The full beamforming gain assumes eight beams per sector for both polarizations, which means, 16-64TRX massive MIMO. That gain is available for the user-specific channel PDSCH/PUSCH, PDCCH/PUCCH, and the Physical Random Access Channel (PRACH). We assume a gain of 22 dBi for the broadcast channel PBCH since eight beams can be used for the common channels. For reference, a passive three-sector antenna at the 2 GHz band typically has a gain of 17-18 dBi and a sub-1-GHz antenna 15 dBi. The antenna gain values naturally depend on the size of the antenna and other antenna parameters. Device antennas have an impact on the link budget. The link budget assumes four-antenna reception in the UE at 3.5 GHz and two-antenna reception at low FDD bands. The base station RF noise figure is assumed to be 