Improved Algorithm for Ground-wave Attenuation Factor Prediction over Irregular Terrain and Results Consistency Study
Zhou Li-li① Mu Zhong-lin② Pu Yu-rong③ Xi Xiao-li③
①(College of Electrical and Information Engineering, Shaanxi University of Science and Technology, Xi’an 710021, China) ②(Unit No. 94559, Xuzhou 221005, China) ③(Xi’an University of Technology, Xi’an 710048, China)
The results of the integral equation method on the low-frequency ground-wave attenuation factor are inconsistent with other classic algorithms for the homogeneous/inhomogeneous smooth-path models. To solve this problem, a spherical correction factor and an elevation converting technique are introduced to the integral equation method. With these efforts, the results of the improved method are more consistent with other algorithms under the smooth-path conditions. Then, it is used for a real irregular-path model, and the calculated results are compared with the measured ones. It is shown that the proposed method is more suitable for the occasions both on the ground and in the air as the propagation path is long, irregular, and curved.
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