dwidth. Therefore, the LTE PDCCH is located at the edge of the carrier. The data channels for LTE and 5G are located in the center of the carrier and switching between LTE and 5G is possible in the time domain, as shown in Figure 10.31. Operating band combinations for the supplemental uplink are shown in Table 10.16. Many of the existing low band LTE options are included, especially for Europe and Asia. 10 5G Performance PUCCH LTE PUCCH 5G PUCCH 5G PUCCH LTE PUSCH 5G PUSCH 5G PUCCH 5G PUCCH LTE PUCCH LTE PUCCH Figure 10.31 Options for frequency sharing between LTE and 5G. Table 10.16 Supplemental uplink band combinations [9]. 5G band Supplemental uplink 5G 3500 (n78) LTE 1800 uplink (n80) 5G 3500 (n78) LTE 900 uplink (n81) 5G 3500 (n78) LTE 800 uplink (n82) 5G 3500 (n78) LTE 700 uplink (n83) 5G 3500 (n78) LTE 2100 uplink (n84) 5G 3500 (n78) LTE AWS uplink (n86) 5G 4500 (n79) LTE 1800 uplink (n80) 5G 4500 (n79) LTE 900 uplink (n81) We should note, however, that Uplink Sharing from UE Perspective (ULSUP) is not mandatory for Release 15 devices. ULSUP refers to the case where 5G uplink and LTE use the same band in the case of dual connectivity. For example, if LTE uses 1800 MHz in dual connectivity, then 5G cannot use 1800 MHz for the supplemental uplink without network explicit resource sharing coordination. The ULSUP discussion is part of 3GPP Release 16. In Release 15, timeframe uplink sharing from the network point of view is the only supported mechanism for uplink sharing. This means that in the case of dual connectivity and supplemental uplink on the same band, it is the anchor LTE eNodeB that is required to control the sharing between LTE and the 5G uplink. 10.6.3.4 Benchmarking of Uplink Solutions Dual connectivity is the first solution to improve the uplink coverage without any extra functionality, because the first 5G devices will anyway support dual connectivity. Dual connectivity has the additional benefit that it is feasible also for inter-site cases. Dual connectivity will increase latency since the up