Question 8.10: Calculate the radiation resistance of a finite dipole antenn...

Fundamentals of Electromagnetics with MATLAB

Calculate the radiation resistance of a finite dipole antenna as a function of the physical length divided by the excitation wavelength.

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The expression for the radiation resistance of a linear antenna is much more complicated than that derived in Example 8.7. It involves new special functions involving sine and cosine integrals, and it is usually considered in books dealing with advanced electromagnetics. Because of this complexity, we will only provide the results here. For additional information, see the referenced text, where the equations are used to generate the graph below with MATLAB. One can see that for the popular case of a half-wave dipole, the radiation resistance is found to be $R_{rad} = 73.1 Ω$ as shown in Problem 8.4.7, which is very close to the measured value.

8.10

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