## 3 Materials and Methods
### Discussion of Results  
The results of the extensive propagation measurements are briefly discussed as follows: The availability of the desired frequencies comprising the available (A) and not available (NA) frequencies captured by the spectrum analyzer was given in Table 5. Specifically, the availability of the desired frequencies for the 18 channels at 6 GHz: 5.945, 5.975, 6.005, 6.034, 6.093, 6.153 GHz, was observed. The available sites were A, C, E, I, L, N, and R, whereas the non-available sites were F, G, and H. The other sites that were tested have some available and non-available frequencies within the desired frequency spectrum. In Figures 5-10, the received power is fairly distributed across the sites. Site H has around 69 dBm in almost all scenarios, and site S has 86 dBm on average. The average power of channels P, Q, R, and S is distinct from the remaining 14 channels for all measurement scenarios. In particular, each average power of the four channels is more than \(-\)80 dBm. Interestingly, these four channels are located in Lagos State, a heavily dense urban environment. The remaining 14 channels are located in Kogi State, a moderately dense urban environment. The results indicate that channel F has both white and colored noise, and it is much noisier than the other channels. Therefore, no desired frequency may be used in channel F.  
Additionally, the histogram and PDF of the frequency scan for sites A, B, C, and D, at 6, 7, and 8 GHz, are presented in Figures 11-34. Interestingly, the spectra data appear to follow a normal distribution for all scenarios. However, there are observed discrepancies with the distributions. These variations may be attributed to the varying degrees of interference from one site to another. Additionally, the cumulative distribution functions of the frequency scan for all sites at 6 GHz, 7 GHz, and 8 GHz are shown in Figures 26, 35 and 37-40. All cumulative distribution functions (CDFs) appear to follow the same trend for all measurement scenarios. The statistical error analyses of the frequency scan measurements for the 6 GHz, 7 GHz, and 8 GHz in horizontal and vertical polarization are presented in Tables 6-11. These include the mean absolute error (MAE), root mean squared error (RMSE), mean absolute percentage error (MAPE), relative absolute error (RAE), and the mean squared error (MSE). Error analysis for the estimated normal distribution (Y) and the estimated fitness curve (F) are tabulated. Here, the first five columns describe the error in PDF, and the last five columns describe the errors in the fitness curve for the 6 GHz, 7 GHz, and 8 GHz horizontal and vertical polarizations. Generally, the MAE and RMSE show the highest error values across tested criteria Y and F. On the other hand, the MAPE, RAE, and MSE show relatively lower values for both the Y and F scenarios. In all scenarios, site S appears to give the highest error statistics. The results of the signal waveforms after noise removal are given in Figures 41-46. These comprise the frequency scan measurements for the sites after denoising and applying the algorithm to all sites, including those without the potential to cause interference. Particularly, only Figures 41 and 42 are discussed for brevity. Figure 41 shows that the signal strength after denoising is about \(-67.5\) dBm for the 6 GHz horizontal polarization scan in site G. This implies that the signals to be deployed must be at least \(-60\) dBm, assuming less interference between signals that differ by 7.5 dBm. Additionally, the maximum signal strength is \(-80\) dBm. This means that signals as low as \(-72.5\) dBm can be deployed at the site without the fear of being interfered with by the existing signals. In the 6 GHz horizontal polarization, the possible sites of interference are G, H, J, K, P, Q, and S. The frequencies of interest labeled F1, F2, F3, F4, F5, and F6 are 5.945 GHz, 5.975 GHz, 6.005 GHz, 6.034 GHz, 6.093 GHz, and 6.153 GHz, respectively.