# Comparative Study of Indoor Propagation Model Below and Above 6 GHz for 5G Wireless Networks
## 6 Results and Discussion
### Power Delay Profile and Time Dispersion Results and Analysis  
Figure 11a,b show the received power for all multipath components at all measurement positions of 3.5 GHz for LOS and NLOS scenarios. For the LOS scenario shown by Figure 11a, it can be shown that most of the received power is concentrated at the early multipath components in the excess delay of less than 10 ns. The highest received power between \(-\)60 dBm to \(-\)50 dBm is found on the first paths (LOS path) and this power is degraded after a Tx-Rx separation distance of 5 m as shown in Figure 11a. The received power between \(-\)75 dB to \(-\)61 dB is concentrated at the first 5 multipath components (MPCs) at a time of less than 5 ns. Most of the MPCs have received power in the range of \(-\)80 dBm to \(-\)76 dBm with an excess delay between 3 ns to 12 ns. Few paths are available at a time above 15 ns with the received power between \(-\)100 dBm to \(-\)76 dBm. For the NLOS scenario, Figure 11b shows that the received power between \(-\)75 dB to \(-\)50 dB is found at the earliest excess delay below 10 ns, while most of the received power is in the range of \(-\)90 dBm to \(-\)77 dBm with excess delay below 30 ns. Some of these MPCs arrived in the range of excess delay 100 ns to 150 ns at the Tx-Rx separation distance between 14 m to 16 m.  
Figure 10: Diffraction loss (DL) and frequency drop (FD) using path gain at different Tx-Rx separation distance. The received power with excess delay at different Tx-Rx separation distance for 28 GHz is shown in Figure 11(a),b for LOS and NLOS scenarios, respectively. Figure 11(a) shows that the highest received power for the LOS scenario in the 28 GHz band is between \(-75\) dB to \(-70\) dBm in the first 5 m Tx-Rx separation distance with excess delay less than 3 ns. Some MPCs with less than 4 ns time delay have received power in the range of \(-80\) dBm to \(-76\) dBm. Most of MPCs are ignored after excess delay of 5 ns. For the NLOS scenario, most of MPCs received power less than \(-100\) dBm with excess delay less than 25 ns as shown in Figure 11(b). A few paths have received power ranging between \(-90\) dBm and \(-60\) dBm. Figure 12(a),b shows the PDPs for 3.5 GHz and 28 GHz bands in LOS and NLOS scenarios respectively, at one Tx-Rx separation distance of 10 m. Figure 12(a), shows the observed MPCs and maximum excess delay for 3.5 GHz and 28 GHz at one pointing angle (the azimuth angle is \(0^{\circ}\) at the Tx and \(60^{\circ}\) at the Rx antennas, and the elevation angle is tilted down at the Rx by \(5^{\circ}\); it is \(0^{\circ}\) at the Tx) for the LOS scenario. In this LOS scenario, it can be shown that using the wide beam horn antenna  
Figure 11: Received power versus time (power delay profile) at all Tx-Rx separation distance in 3.5 GHz band for (**a**) LOS (**b**) NLOS. Figure 12: Received power versus time (power delay profile) at all Tx-Rx separation distance in 28 GHz band for (**a**) LOS (**b**) NLOS. although the Rx azimuth was shifted 60\({}^{\circ}\) from the Tx angle of 0\({}^{\circ}\) and the Rx elevation angle was down tilted 5\({}^{\circ}\) from the Tx angle of 0\({}^{\circ}\), the directed path (LOS path) remains the first MPC with maximum power in both bands. The maximum excess are 12 ns and 9 ns for 3.5 GHz and 28 GHz, respectively. For NLOS scenario, Figure 13b, shows the observed MPCs and maximum excess delay for 3.5 GHz and 28 GHz at one pointing angle (the azimuth angle is 45\({}^{\circ}\) at the Tx and 60\({}^{\circ}\) at the Rx antennas, and the elevation angle is tilted down at the Rx by 5\({}^{\circ}\); it is 0\({}^{\circ}\) at the Tx). Figure 13b shows the strongest path is not the first one for both frequencies because no directed path in NLOS scenario, and the maximum excess delay are more than the excess delay of LOS scenario by 32 ns for both frequencies. The RMS delay spread versus Tx-Rx separation distance in both bands for LOS scenario is shown in Figure 14a. The RMS delay spread values for both frequencies are low.