Fundamentals Of Applied Electromagnetics
7th Edition
ISBN: 9781292082448
Author: Fawwaz T Ulaby Umberto Ravaioli
Publisher: Pearson Education Dorling Kindersley
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Textbook Question
Chapter 9.8, Problem 13E
What condition must be satisfied in order to use scalar diffraction to compute the field radiated by an aperture antenna? Can we use it to compute the directional pattern of the eye’s pupil (d ≃ 0.2 cm) in the visible part of the spectrum (λ = 0.35 to 0.7 μm)? What would the beamwidth of the eye’s directional pattern be at λ = 0.5 μm?
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Chapter 9 Solutions
Fundamentals Of Applied Electromagnetics
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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