A vertical lambda/2 dipole antenna is used as a ground-to-air, over-the- horizon communication antenna at the VHF band (f = 200MHz). The antenna is elevated at a height h (measured from its center/feed point) above ground (assume the ground is flat, smooth, and perfect electric conductor extending to infinity'). In order to avoid interference with other simultaneously operating communication systems, it is desired to place a null in the far-field amplitude pattern of the antenna system at an angle of 60degree from the vertical. Determine the three smallest physical/nontrivial heights (in meters at 200 MHz) above the ground at which the antenna can be placed to meet the desired pattern specifications.

A vertical lambda/2 dipole antenna is used as a ground-to-air, over-the- horizon communication antenna at the VHF band (f = 200MHz). The antenna is elevated at a height h (measured from its center/feed point) above ground (assume the ground is flat, smooth, and perfect electric conductor extending to infinity'). In order to avoid interference with other simultaneously operating communication systems, it is desired to place a null in the far-field amplitude pattern of the antenna system at an angle of 60degree from the vertical. Determine the three smallest physical/nontrivial heights (in meters at 200 MHz) above the ground at which the antenna can be placed to meet the desired pattern specifications.

Introductory Circuit Analysis (13th Edition)

13th Edition

ISBN:9780133923605

Author:Robert L. Boylestad

Publisher:Robert L. Boylestad

Chapter1: Introduction

Section: Chapter Questions

Problem 1P: Visit your local library (at school or home) and describe the extent to which it provides literature...

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