# Performance Analysis of Downlink 5G Networks in Realistic Environments
## 6 Simulation Results with Discussion
To validate the results, the provided results in Figure 16 are compared against ITU-T requirements [44; 45; 46] for 5G networks. It can be noticed that benchmarking results are achieved on all types of services; however, the best results for streaming are achieved when the total offered bit rate increases (>125 Mbit/s). This is expected since real-time streaming needs a higher bit rate compared to voice and web browsing. We expect a lower average bit rate in zone 2 for all service categories, as illustrated in Figure 17, and it even decreases in zone 3, as illustrated in Figure 18. To confirm these results, the aggregate average bit rate is presented in Figures 19-21 in all zones for each type of service. For example, in Figure 19, the streaming is shown in all zones, and it is shown more clearly that a maximum bit rate of around 3.5 Mbit/s can be achieved at a load of 230 Mbit/s in zone 1 compared to around 1.8 Mbit/s in zone 2 (Figure 20) and around 2.5 Mbit/s in zone 3 (Figure 21). Figure 6:0 Uplink capacities of multiple channels. Figure 6:1 Uplink capacity for different interference factors, \(\varepsilon\). For more validation and confirmation of the status in Figure 16 regarding video streaming, the results are compared again in Figure 19 against ITU-T requirements. It can be noticed that the average bit rate required for video streaming is higher in zone 1 compared to other zones because the traffic density in zone 1 is higher. This is why better video streaming quality can be achieved at a higher offered bit rate (>104 Mbit/s). Starting from this rate, the video streaming levels start matching with the ITU-T requirements compared to the matching that happened earlier at lower bit rates for other services. The overall cell performance is given in Figures 22-27. Due to the use of the cyclic prefix method in 5G, inter-cell interference and inter-symbol interference will be improved. Subsequently, starting from Figure 22, the average bit rate in the entire cell is maximized to approximately 21 Mbit/s when the average bit rate is low (42 Mbit/s) because the overall number of users who request service at this load is small compared to 11 Mbit/s at a high bit rate of 230 Mbit/s. Therefore, few users will enjoy the maximum rate under all circumstances and for different service categories. When the load increases, the number of users increases, and the resources are shared with more users. This is why the performance of the cell degraded at higher loads (230 Mbit/s) (Figure 23) where a higher number of users were blocked. Figure 6:2 Aggregate average bit rate in zone 1. Figure 6:3 Aggregate average bit rate in zone 2. Figure 6:4 Aggregate average bit rate for streaming across zones. Figure 6:5 Aggregate average bitrate for voice over 5G in all zones. The cell delay budget is shown in Figure 6:6 It can be noticed that optimal values for the cell delay budget are obtained as per the 3 GPP and ITU-T standards [44; 45; 46]. The delay starts at approximately 20 ms at a bit rate of 42 Mbit/s and goes down to approximately 11 ms when the bit rate increases to 230 Mbit/s. For the sake of comparison and validation of the results, the cell delay budget in Figure 24 and the loss probability in Figure 25 are compared against the ITU-T requirements. It can clearly be seen in Figure 24 that the cell budget delay complies with the 3 GPP and ITU-T requirements at different offered bit rates, and a good matching with the requirements is shown. Similar behavior can be noticed for the loss probability figure; however, regarding loss probability, complete matching with the requirement can be seen at a higher bit rate (>104 Mbit/s). This is a very good observation because when the offered bit rate increases, the probability of loss increases. To overcome this increase, the system needs an efficient call admission control algorithm. It appears that the call admission control algorithm works very well in terms of balancing the load over the cell.