UNIVERSITY OF ARIZONA
Department of Electrical and Computer Engineering
ECE 381 Section 1 Fall 2011 Ziolkowski
Hour Exam 2 ' October 24, 2011
You can ACE this exam Think
No guessing allowedl! Remember that partial credit will be given
I) we
NAME: 30
UNIVERSITY OF ARIZONA
Department of Electrical and Computer Engineering
ECE 38 1 Section 1
Exam I
You can ACE this exam!
No guessing allowed!
NAME:
Score:
TOTAL SCORE:
Ziolkowski
Spring 2009
February 11,2009
Think!
Remember that partial credit will be giv
University of Arizona
Department of Electrical and Computer Engineering
ECE 381 Homework Set 1
Fall 2011
August 29, 2011
Ziolkowski
Mandatory Problems on Phasors and Wave Concepts
1. Ulaby Problem 1.4
2. Ulaby Problem 1.8
3. Ulaby Problem 1.13
4. Ulaby Pr
University of Arizona
Department of Electrical and Computer Engineering
ECE 381 Homework Set 4
Fall 2011
September 19, 2011
Ziolkowski
Mandatory Problems on Input Impedance and Transmission Lines
1. (40 pts) Consider the transmission line system shown bel
Problem I. Use the Smith chart to nd the reection eneeient mpuuding
ta a load impedance ef
cfw_a 2L = 3-2:.
(h: 2:. = cfw_2 zu
cfw_c 2L = zu
[d] 21 = a (short circuit
Snluen: Refer to Fig. PEA-1T.
cfw_a Point A iszL = 3 13.1": Men"
cfw_11 Emma iszL = 2 J1
ECE 381-HW#10
7.11, 7.19, 7.23, 7.28, & 8.1
e = x ax e jkz can be
Problem 7.11 A linearly polarized plane wave of the form E
expressed as the sum of an RHC polarized wave with magnitude aR , and an LHC
polarized wave with magnitude aL . Prove this stateme
RCS
Comparisons
Goals of Antenna Design
High overall efficiency
Large bandwidth
High directivity
Cheap, light weight, easy to fabricate
Efficiencies
Transmission
Lines
E, H
Source
Antenna
Pradiated = eoverall Pinput
= e radiation Paccepted
(
= e radiation
UNIVERSITY OF ARIZONA
Department of Electrical and Computer Engineering
ECE 381 Section 1 Spring 2009 Ziolkowski
Hour Exam 2 March 13, 2009
You can ACE this exam! Think!
No guessing allowedl! Remember that partial credit will be given
Score:
2' O (20)
PP
Problem 8.18 For some types of glass, the index of refraction varies with
wavelength. A prism made of a material with
n = 1.71
4
0
30
(0 in m),
where 0 is the wavelength in vacuum, was used to disperse white light as shown in
Fig. P8.18. The white light
Problem 7.19 Ignoring reection at the airsoil boundary, if the amplitude of a
3-GHz incident wave is 10 V/m at the surface of a wet soil medium, at what depth will
it be down to 1 mV/m? Wet soil is characterized by r = 1, r = 9, and = 5 104
S/m.
Solution:
Problem 1.4 A wave traveling along a string is given by
y(x, t ) = 2 sin(4 t + 10 x) (cm),
where x is the distance along the string in meters and y is the vertical displacement.
Determine: (a) the direction of wave travel, (b) the reference phase 0 , (c)
Problem 2.1 A transmission line of length l connects a load to a sinusoidal voltage
source with an oscillation frequency f . Assuming the velocity of wave propagation
on the line is c, for which of the following situations is it reasonable to ignore the
p
Problem 2.20 A 300- lossless air transmission line is connected to a complex
load composed of a resistor in series with an inductor, as shown in Fig. P2.20. At
5 MHz, determine: (a) , (b) S, (c) location of voltage maximum nearest to the load,
and (d) loc
Problem 2.27 At an operating frequency of 300 MHz, a lossless 50- air-spaced
transmission line 2.5 m in length is terminated with an impedance ZL = (40 + j20) .
Find the input impedance.
Solution: Given a lossless transmission line, Z0 = 50 , f = 300 MHz,
Problem 4.24 Charge Q1 is uniformly distributed over a thin spherical shell of
radius a, and charge Q2 is uniformly distributed over a second spherical shell of
radius b, with b > a. Apply Gausss law to nd E in the regions R < a, a < R < b,
and R > b.
Sol
Problem 4.48 With reference to Fig. 4-19, nd E1 if E2 = x3 y2 + z2 (V/m),
1 = 20 ,
2 = 180 , and the boundary has a surface charge density
s = 3.54 1011 (C/m2 ). What angle does E2 make with the z-axis?
Solution: We know that E1t = E2t for any 2 media. H
Problem 5.19 Three long, parallel wires are arranged as shown in Fig. P5.19.
Determine the force per unit length acting on the wire carrying I3 .
I1 = 10 A
2m
I3 = 10 A
2m
2m
I2 = 10 A
Figure P5.19: Three parallel wires of Problem 5.19.
Solution: Since I1
Problem 6.11 The loop shown in P6.11 moves away from a wire carrying a current
I1 = 10 A at a constant velocity u = y7.5 (m/s). If R = 10 and the direction of I2 is
as dened in the gure, nd I2 as a function of y0 , the distance between the wire and
the lo
/ 9
Problem 7.4 The electric eld of a plane wave propagating in a nonmagnetic
material is given by
E = [y 3 sin( 107t 0.2 x)
+ z 4 cos( 107t 0.2 x)] (V/m)
Determine
(a) The wavelength.
(b) r .
(c) H.
Solution:
(a) Since k = 0.2 ,
=
(b)
up =
2
2
= 10 m.
=
University of Arizona
Department of Electrical and Computer Engineering
ECE 381 Homework Set 11
Fall 2011
November 28, 2011
Ziolkowski
Mandatory Problems on Oblique Incidence Scattering and Antennas
1. Ulaby Problem 8.18
2. Ulaby Problem 8.27
3. Ulaby Pro
(25) 3. A hyperthermia tumor treatment applicator is being modeled as a plane wave
source. The plane wave from the source propagates in lossy muscle tissue. The plane
wave is assumed to be propagating along the positive z-direction. It is linearly polariz
Problem 8.18 For some types of glass, the index of refraction varies with
wavelength. A prism made of a material with
n = 1.71
4
0
30
(0 in m),
where 0 is the wavelength in vacuum, was used to disperse white light as shown in
Fig. P8.18. The white light
/ 9
Problem 7.4 The electric field of a plane wave propagating in a nonmagnetic
material is given by
E = [y 3 sin( 107t 0.2 x)
+ z 4 cos( 107t 0.2 x)] (V/m)
Determine
(a) The wavelength.
(b) r .
(c) H.
Solution:
(a) Since k = 0.2 ,
=
(b)
up =
2
2
= 10 m.
University of Arizona
Department of Electrical and Computer Engineering
ECE 381 Homework Set 9
Spring 2017
March 29, 2017
Ziolkowski
Mandatory Problems on 1D Plane Waves in Lossless Media
(50 pts) 1. Consider an uniform electromagnetic plane wave that is
University of Arizona
Department of Electrical and Computer Engineering
ECE 381 Homework Set 2
Spring 2017
January 18, 2017
Ziolkowski
Mandatory Problems on Transmission Lines without Loads
1. Ulaby Problem 2.1
2. Ulaby Problem 2.4
3. Ulaby Problem 2.5
(5
University of Arizona
Department of Electrical and Computer Engineering
ECE 381 Homework Set 3
Spring 2017
January 25, 2017
Ziolkowski
Mandatory Problems on Lossless Transmission Lines with Loads
1. Ulaby Problem 2.20
2. Ulaby Problem 2.23
3. Ulaby Proble