ilable for the single knife edge obstacle. Table 6.1 shows that the estimated path loss results obtained for the UTD-PO and the FKE approaches had mean errors of 0.2647 dB and 0.2648 db, respectively. When compared to the mean error result predicted for the FKE approach, the predicted result for the UTD-PO approach indicates a marginal improvement of 0.0001 dB. Also, data analysis for single knife edge obstacle when transmitter T is below the obstacle shows that the UTD-PO and the FKE approaches give the same results. Figure 6.11 shows the prediction of path loss over two knife edge obstacles where transmitter T of height hix 39.17 Ais below the first obstacle of height hobtl of 42.83 2 and it is placed 96.08 Aaway from the first obstacle. The second obstacle of height hob12 of 42.83 is placed 16.91 2 away from the first obstacle. The receiver R is placed 96.08 Aaway from the second obstacle in the shadowed region. Propagation path loss is predicted when the receiver moves from NLOS to LOS vertically. The path loss UTD-PO and FKE Models for Path Loss Prediction Measurement Data UTD-PO (LOS) (NLOS) 96.082 96.082 16.912 Height (m) FIGURE 6.11 A comparison of the path loss obtained for two knife edge obstacles using the UTD-PO and the FKE approaches with the available measurement data. results obtained for the UTD-PO and the FKE approaches show the same results when compared with the measurement data available for the two-knife edge obstacle. Table 6.1 shows that the estimated path loss results obtained for the UTD-PO and the FKE approaches had mean errors of 1.2192 dB and 2.7065 dB, respectively. When compared to the mean error result predicted for the FKE approach, the predicted result for the UTD-PO approach indicates a significant improvement of 1.4873 dB. Also, data analysis for the two knife edge obstacles shows that UTD-PO approach gives a better result than the FKE approach. Figure 6.12 shows a prediction of path loss over the multiple knife-edge obstacles where transmitter T of height hix of 46.42 Ais above