rate the impact of the following factors: UE placement, foliage, and cell size. Two different foliage assumptions are considered: no foliage and heavy foliage. Foliage refers to the leaves of trees and plants which cause additional attenuation at high frequencies. Three different inter-site distances are considered: 100, 200, and 300 m. Simulation results are illustrated in three separate plots: average downlink data rates in Figure 10.5, cell edge downlink in Figure 10.6, and cell edge uplink in Figure 10.7. We can make the following notes from the simulations: An average downlink data rate of 500 Mbps and cell edge data rate of 100 Mbps can be achieved with an inter-site distance of 300 m without foliage with outdoor instal- lations, 200 m with heavy foliage with outdoor installations, and 100 m with indoor installations. Uplink data rates are lower than downlink rates due to the lower UE transmission power. An average rate of 300 Mbps and cell edge rate of 100 Mbps can be achieved only with 100 m inter-site distance and outdoor installations if heavy foliage is consid- ered. An inter-site distance of 200 or 300 m can be achieved for outdoor installations without foliage. More details can be found in [3]. 10.4 Latency Uplink cell edge user data rate in fixed wireless case Mbps 300 No foliage No foliage No foliage foliage foliage foliage 100 m 200 m 300 m Figure 10.7 Cell edge uplink user data rates with fixed wireless deployment at 28 GHz. 10.4 Latency 10.4.1 User Plane Latency Low latency communication (LLC) is one of the targets in 5G networks. Latency min- imization is considered important for mission-critical communication. Low latency is also beneficial for interactive applications and for protocol performance. Data rate and spectral efficiency have theoretical limits defined by the bandwidth, signal-to-noise ratio (SNR), and the Shannon limit [4]. There are no such theoretical limits for latency. The limit is just a practical protocol design which is a trade-off between performance, effi- ciency, and comp