Computation of Diffraction Parameter as a Function of Line of Site Percentage Clearance

Nathaniel Chimaobi Nnadi, Charles Chukwuemeka Nnadi, Ifeanyi Chima Nnadi


In this paper, mathematical expression and method for computing   diffraction parameter as a function of line of site percentage clearance is presented. The concept of line of site percentage clearance scaling factor is introduced. The scaling factor  makes it possible to determine the diffraction parameter at different of line of site percentage clearances when the value of  diffraction parameter is known at one particular line of site percentage clearance. Particularly, for Fresnel zone n and  line of site percentage given as P_(c(x,n)), the diffraction parameter , V_((x,pc))    is given as V_((x,pc))   =(((√2 n)P_(c(x,n))  )/100). Also, for any two line of site percentages given as P_(c(x,n)(1)) and P_(c(x,n)(2)), the  line of site percentage clearance scaling factor is given as (P_(c(x,n)(2))/(P_(c(x,n)(1))  )). If the diffraction parameter at P_(c(x,n)(1))  is given as V_((x,pc1)  ), then  the diffraction parameter at P_(c(x,n)(2))  is given as V_((x,pc2)  )=V_((x,pc1)  ) (P_(c(x,n)(2))/(P_(c(x,n)(1))  )). The mathematical expressions and method  are applied to a 3 GHz  microwave link with path length of 38887.6 m. The results obtained demonstrated the validity of the mathematical expressions and method presented in the paper.


Diffraction Parameter; Fresnel Zone; Microwave Link; Percentage Clearance; Line of Site Communication

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