EBK FUNDAMENTALS OF APPLIED ELECTROMAGN
7th Edition
ISBN: 8220100663659
Author: ULABY
Publisher: PEARSON
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Textbook Question
Chapter 9, Problem 33P
An antenna with a circular aperture has a circular beam with a beamwidth of 3° at 20 GHz.
- (a) What is the antenna directivity in dB?
- (b) If the antenna area is doubled, what will be the new directivity and new beamwidth?
- (c) If the aperture is kept the same as in (a), but the frequency is doubled to 40 GHz, what will the directivity and beamwidth become then?
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Chapter 9 Solutions
EBK FUNDAMENTALS OF APPLIED ELECTROMAGN
Ch. 9.1 - What does it mean to say that most antennas are...Ch. 9.1 - What is the radiated wave like in the far-field...Ch. 9.1 - In a Hertzian dipole, what is the underlying...Ch. 9.1 - Outline the basic steps used to relate the current...Ch. 9.1 - A 1 m long dipole is excited by a 5 MHz current...Ch. 9.2 - Prob. 5CQCh. 9.2 - What is the magnitude of the directivity of an...Ch. 9.2 - An antenna has a conical radiation pattern with a...Ch. 9.2 - Prob. 3ECh. 9.3 - What is the physical length of a half-wave dipole...
Ch. 9.3 - How does the radiation pattern of a half-wave...Ch. 9.3 - How does the radiation efficiency of a...Ch. 9.3 - Prob. 4ECh. 9.3 - Prob. 5ECh. 9.5 - Prob. 6ECh. 9.5 - At 100 MHz, the pattern solid angle of an antenna...Ch. 9.6 - If the operating frequency of the communication...Ch. 9.6 - Prob. 9ECh. 9.6 - Prob. 10ECh. 9.8 - Verify that Eq. (9.86) is a solution of Eq. (9.85)...Ch. 9.8 - Prob. 12ECh. 9.8 - What condition must be satisfied in order to use...Ch. 9.8 - Derive an expression for the array factor of a...Ch. 9.8 - Prob. 15ECh. 9.11 - Prob. 11CQCh. 9.11 - Prob. 12CQCh. 9.11 - Prob. 13CQCh. 9.11 - Prob. 14CQCh. 9.11 - Prob. 15CQCh. 9 - A center-fed Hertzian dipole is excited by a...Ch. 9 - A 50 cm long center-fed dipole directed along the...Ch. 9 - Prob. 3PCh. 9 - Determine the following: (a) The direction of...Ch. 9 - Repeat Problem 9.4 for an antenna with...Ch. 9 - A 2 m long center-fed dipole antenna operates in...Ch. 9 - Repeat Problem 9.6 for a 20 cm long antenna...Ch. 9 - Prob. 9PCh. 9 - An antenna with a radiation efficiency of 90% has...Ch. 9 - Prob. 11PCh. 9 - The normalized radiation intensity of a certain...Ch. 9 - Repeat Problem 9.6 for a 1 m long half-wave dipole...Ch. 9 - Prob. 14PCh. 9 - A 50 cm long dipole is excited by a sinusoidally...Ch. 9 - Prob. 16PCh. 9 - For a dipole antenna of length l = 3/2, (a)...Ch. 9 - Prob. 18PCh. 9 - Prob. 19PCh. 9 - Prob. 20PCh. 9 - A car antenna is a vertical monopole over a...Ch. 9 - Determine the effective area of a half-wave dipole...Ch. 9 - A 3 GHz line-of-sight microwave communication link...Ch. 9 - A half-wave dipole TV broadcast antenna transmits...Ch. 9 - A 150 MHz communication link consists of two...Ch. 9 - Consider the communication system shown in Fig....Ch. 9 - The configuration shown in Fig. P9.27 depicts two...Ch. 9 - Prob. 28PCh. 9 - The configuration shown in Fig. P9.29 depicts a...Ch. 9 - Prob. 30PCh. 9 - Prob. 31PCh. 9 - A uniformly illuminated rectangular aperture...Ch. 9 - An antenna with a circular aperture has a circular...Ch. 9 - Prob. 34PCh. 9 - Prob. 35PCh. 9 - Prob. 36PCh. 9 - Prob. 37PCh. 9 - Prob. 38PCh. 9 - Prob. 39PCh. 9 - Prob. 40PCh. 9 - Find and plot the normalized array factor and...Ch. 9 - Prob. 44PCh. 9 - A three-element linear array of isotropic sources...Ch. 9 - An eight-element linear array with /2 spacing is...Ch. 9 - A linear array arranged along the z axis consists...
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