Fundamentals of Electromagnetics with MATLAB 2nd. Edition by Lonngren, Karl E. | 9781891121586 | 1891121588 | Holooly

Electromagnetics

Fundamentals of Electromagnetics with MATLAB

167 SOLVED PROBLEMS

Question: 6.21

(a) Find the phase and group velocities for a normal transmission line depicted below. (b) Find the phase and group velocities for a transmission line in which the circuit elements are interchanged. ...

Verified Answer:

(a) From (6.77), we write

\gamma=\alpha+j ...

Question: 4.26

Two charged parallel square plates with dimensions L × L = 1 m² are separated by a distance of d = 0.1 m. Each side is subdivided into N = 64 equal subareas. The potential of the top plate is + 5 V, and the potential of the bottom plate is – 5 V. (a) Find and plot the charge density distribution ...

Verified Answer:

(a) The column vector of the known potential is [l...

Question: 4.18

Determine the potential distribution within the two adjacent triangular regions if the potential is specified at all nodes V1 = 8 @ ( 4, 0); V2 = 0 @ (0, 0); V3 = 0 @ (4, 3); and V4 = 8 @ (0, 3). ...

Verified Answer:

The voltage distribution in the triangle (1, 2, 3)...

Question: 8.7

Find the radiation resistance of an infinitesimal dipole. ...

Verified Answer:

The radiated power

P_{rad}

from the...

Question: 8.18

Compare the directivities of two arrays consisting of three identical elements separated by a half wavelength for the following two cases: (a) Uniform array: (I-1 = I0 = I1 = 1 A). (b) Binomial array: (I-1 = I1 = 1 A; I0 = 2A). ...

Verified Answer:

From (8.71), we compute

D = \frac{\left\lgr...

Question: 8.17

Find the current in one of the dipoles in an antenna array if there is (a) No mutual coupling between the dipoles. (b) A mutual coupling between the dipoles. The driving voltage is V1 = 100 V and the distance between the two half-wave dipoles is d = λ/2. Estimate the amplitude and the phase change. ...

Verified Answer:

(a) For the case with no mutual coupling, we can a...

Question: 8.16

Using the concept of the multiplication of patterns, find the radiation pattern of the array of four elements as shown in the figure. ...

Verified Answer:

This array is to be replaced with an array of two ...

Question: 8.15

Find and plot the radiation pattern of two parallel thin half-wavelength electric dipoles separated by d = λ/2, λ, and 3λ/2. The mutual coupling of the dipoles is neglected. ...

Verified Answer:

Here the radiation pattern of this linear array is...

Question: 8.14

Find and plot the array factor for three two-element antenna arrays, that differ only in the separation distance between the elements. Assume the two elements for each antenna array are isotropic radiators. The antennas are separated by 5, 10, and 20 cm, and each antenna is excited in phase. The ...

Verified Answer:

The separation between the elements is normalized ...

Question: 8.13

Find a criterion for the argument that a receiving antenna actually is in the far field of a transmitting antenna. Estimate the distance d of the far zone if D = 10 cm and λ = 3 cm. Assume that they have antenna gains GA = 1.5 and GB = 1.64, respectively, and find the ratio Pr/Pt, at that distance. ...

Verified Answer:

For the Friis transmission equation to be applicab...

Loading...