Fundamentals of Applied Electromagnetics (7th Edition)
7th Edition
ISBN: 9780133356984
Author: ULABY
Publisher: PEARSON
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Chapter 9, Problem 10P
An antenna with a radiation efficiency of 90% has a directivity of 7.0 dB. What is its gain in decibels?
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I need a detailed solution to a
problem.
The far-zone electric field intensity (array factor) of an end-fire two-element array
antenna, placed along the z-axis and radiating into free-space, is given by
E=cos (cos - 1)
Find the directivity using
(a) Kraus' approximate formula
(b) the DIRECTIVITY computer program at the end of this chapter
Repeat Problem 2.19 when
E = cos
-jkr
0505π
$[
(cos + 1)
(a). Elmax = Cost (case-1)] | max"
= 1 at 8-0°.
0.707 Emax = 0.707.(1) = cos [(cose,-1)]
(cose-1) =
± 0,= {Cos' (2)
= does not exist
(105(0)=
90° = rad.
Bir
Do≈ 4T
ar=2() =
=
Bar
4-1-273 = 1.049 dB
T₂
a. Elmax = cos((cose +1)),
0.707 = cos (Close,+1))
= 1
at 6 = π
Imax
(Cose+1)=== G₁ = cos(-2) does not exist.
Girar=2()=π.
4T
\cos (0) + 90° + rad
Do≈ = +=1.273=1.049dB
IT 2
I need an expert mathematical solution.
The E-field pattern of an antenna. independent of , varies as follows:
0° ≤ 0≤ 45°
E = 0
45°
{1
90°
90° < 0 ≤ 180°
(a) What is the directivity of this antenna?
(b) What is the radiation resistance of the antenna at 200 m from it if the field is equal
to 10 V/m (rms) for Ø
=
0° at that distance and the terminal current is 5 A (rms)?
I need an expert mathematical solution.
The normalized far-zone field pattern of an antenna is given by
E =
{®
(sin
cos)/
0
Find the directivity using
0 ≤ 0 ≤ π and 0≤ 0≤ π/2.
3m2sds2,
elsewhere
Chapter 9 Solutions
Fundamentals of Applied Electromagnetics (7th Edition)
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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How does an Antenna work? | ICT #4; Author: Lesics;https://www.youtube.com/watch?v=ZaXm6wau-jc;License: Standard Youtube License