measurement. As shown in Figure 4(a), points 20 to 22 and points 24 to 28 are the LOS paths, and the effect of diffraction has been considered from points 1 to 19 and 23 because of the metal cabinet and the metal partition. Figure 4( b) shows the comparison between the measurement and simulation results from the Programmable Logic Control Laboratory. It is seen that the measured results are close to the simulated results when the influence of diffraction is considered. The mean error is about 2 dB. CONCLUSIONA new multipath propagation-prediction model to be used inside buildings has been proposed in this paper. It shows that the simulation results can predict the path loss correctly. However, this new method also provides low computational load, as compared to ray-tracing techniques. Diffraction plays an important role in this model in order to be able to predict accurately and easily inside buildings with metallic furniture. Future work will focus on the performance of some more complicated environments that have more obstacles and diffraction points.

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Accelerated investments on wind power projects because of the great demand for renewable energy are increasing the concerns about deteriorating effects of wind turbines on the performance of civil and military radar, navigation and communications systems. In this study, the authors introduce a preliminary set of analysis for assessing the performance of electronic systems such as radar, communications and navigation systems and the degrading/deteriorating effects of wind turbines. The analysis quantifies the performance degradation in the electronic systems. The proposed study can be used as a tool by decision makers in the planning and designing phases of both electronic systems and wind turbines to reduce the adverse effects of the wind farms on the mentioned systems.