Antenna 1st Exam

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Kingdom of Saudi Arabia
Ministry of Higher Education
Majmaah University
College of Engineering
Department: Electrical Engineering
Exam Information
Course code:
Instructor:
Section number:
Exam time:
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Number of pages:
First Exam
EE 435
Course Title: Antenna and wave
propagation
Dr Yazeed Qasaymeh
Exam date:
10 November 2014
From:
10:00 am
To:
12:00 pm
3D038
4
Total score:
20 points
Student’s Information
Name:
ID:
Exam Instructions:
 Read the questions carefully and several times. Writing clearly will make
it possible to assess your answers correctly.
 Any form of cheating, intention to cheating, or disruption of the exam will
subject you to a disciplinary action as specified by the university’s
regulations.
 Carrying or using the mobile phone during the exam is not allowed. Using
the phone during the exam will carry a disciplinary action.
 The calculator is only permitted by the exam supervisor.
 No student can leave the exam room during the first half hour of the
exam. Any student coming after the first half hour of the exam will not be
permitted to enter the exam.
 A student leaving the exam, even for legitimate reasons, may not be given
a makeup exam.
Points Earned:
Question
1
2
3
4
Score
Total score in the exam:
Dear student, we encourage you to answer the exam the best you can and we
wish you all success.
Q1) Locate the pattern parameters in the following normalized antenna power
pattern (5PTS)
Q2) the radial component of the radiated power density of an antenna is given by
W rad W r .ar  Ao
Where
sin( )
.ar
r2
Ao is the peak value of the power density.
 is the usual spherical coordinate.
ar is the radial unit vector.
a) Determine the total radiated power. (2PTS)
b) Write an expression of the directivity as a function of the directional angels
 and  (3PTS)
Q3) the radial component of the radiated power density of an infinitesimal
dipole of length L   is given by:
W rad
Where
sin 2 ( )
W r .ar  Ao
.ar
r2
Ao is the peak value of the power density.
 is the usual spherical coordinate.
ar is the radial unit vector.
a) Determine the maximum value directivity of the antenna (3PTS)
b) Express the directivity as a function of the directional angles  and  (2PTS)
Q4) a lossless resonant half-wave dipole antenna with input impedance of 73
Ohm is to be connected to a transmission line whose characteristics impedance
is 50 Ohm assuming that the pattern of the antenna is given approximately by
U  B 0 sin 3 ( )
Find the overall maximum gain of the antenna. (5PTS)
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