Abstract
In this paper, comparative study of the ITU 526-13 method and the occultation distance-based method for computing the radius of curvature for rounded edged fitted to the vertex of hilltop obstruction is presented. In the study, path profiles of microwave links with isolated single edged hilltop and another path profile with isolated double edged hilltop are used. The frequencies considered are from the 1.5GHz in the L-band to 36GHz in the K-band. The result show that for all the frequencies considered, the occultation distance for the single edged hilltop remained constant at 80.923 m and that for the double edged hilltop remained constant at 532.203 m. Also, while the radius of curvature by the ITU 526-13 method varies with frequency in the two path profiles considered, the radius of curvature by the occultation distance method remained constant for all the frequencies considered in each of the two path profiles considered. Also, for the double edged hilltop, the radius of curvature from ITU 526-13 method greatly exceeded the radius of curvature by the occultation distance method for all the frequencies considered. The least difference in about 58% at frequency of 1.5GHz and the difference increased to about 115% at 36GHz. However, for the single edged hilltop, the radius of curvature for the two methods are relatively equal for frequencies above 6GHz. Essentially, ITU 526-13 method works well like the occultation distance-based method for the single edged hilltop. Further studies are therefore required to determine the situations under which the ITU 526-13 method can be applied in computing the radius of curvature for rounded edge approximation used in diffraction loss computation.
Highlights
In line-of-sight (LOS) microwave communication system significant diffraction loss occurs when obstruction in the signal path extends into the first Fresnel zone [1,2,3,4,5,6,7,8]
While the radius of curvature by the ITU 526-13 method varies with frequency in each of the two cases considered, the radius of curvature by the occultation distance method remained constant for all the frequencies considered in each of the two path profiles considered
The ITU 526-13 method and the occultation distance-based method for computing the radius of curvature for rounded edged fitted to the vertex of hilltop obstruction is presented
Summary
In line-of-sight (LOS) microwave communication system significant diffraction loss occurs when obstruction in the signal path extends into the first Fresnel zone [1,2,3,4,5,6,7,8]. In the determination of the rounded edge diffraction loss, the occultation distance is given as that distance between the two tangents points near the vertex of the obstruction profile. The distance between the two tangent points on the path profile gives the occultation distance which is used to determine the radius of curvature or the rounded edge fitted to the vertex of the hill obstruction. Another method of computing the radius of curvature for the rounded edge diffraction obstruction is the ITU-R 526-13 method [22]. The effect of frequency on the radius of curvature by the two methods is studied and their results are compared based on sample rounded edge obstruction in the signal path of a LOS microwave link
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: American Journal of Software Engineering and Applications
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
