QUESTIONS/SUGGESTIONS

1) Compute the dipole input impedance Zin for various values of the length to radius ratios:

100, 200, 500, 1000, 2000 and 25000. Choose a frequency between 950 MHz and 2.88 GHz.

Present your result in a tabular form. Specify exactly the values of L and a conforming to the ratios.

2) For the above data in part 1), prepare a dipole model and obtain the full-wave results for the dipole

input impedance. Compare the analytical results in part 1) against the results in part 2). Present

your result in tabulated form.

3) Next, choose a fixed length of the dipole and its radius. Select a frequency fo in the range between

950 MHz and 2.88 GHz such that the dipole is exactly at the frequency of your choice. Now

vary the frequency, keeping all the other data fixed, and compute the input impedance. (Though

L and a are formally fixed due to the choice of fo, varying the frequency changes the kL and ka;

this changes the dipole input impedance.) Plot the variations of Rin and Xin vs. kL and ka. (This

is using the analytical result.)

4) Repeat the process in part 3) but using an appropriate CAD software. Compare your results against

analytical results you obtained in part 3).

5) Going by the results you have obtained in parts 1) through 4), comment on the validation of the

analytical formulas. How does the approximation break down? Which ratios show the best

agreements between analytical and full-wave numerical results?