PHAROS UNIVERSITY
Faculty of Engineering
Electrical Engineering Department
Division of Communications & Electronics
Subject Name: EE 262 (Microwave Engineering)
Lecturer(s): Dr. Aida EL Shafie, Eng. Heba
Fall 2012
Raafat
SHEET 2 Transmission Line Theory
The Smith Chart
1. On a single 50
Smith Chart, plot the following impedance points:
(a) ZLA = 30 + j 100 , what is ГLA? What is normalized admittance YLA’?
(b) ГLB = 0.5/−100°, what is ZLB?
(c) ZLD = 20 − j 70 in parallel with 80 + j 100 , what is ГLD?
(d) ZLE is ZLA but with 0.15λ transmission line in front of it, what is ГLE?
(e) All the locations for VSWR = 1.5, what is Г?
Smith chart exercises for the mind and spirit). DO NOT USE A CALCULATOR, only the Smith Chart
Answer: (a) 0.8/50°, 0.13 – j0.46, (b) 26 – j35, (c) 0.32/-89.35°, (d) 0.8 /-58°, (e) 0.2.
2. A 30 m long lossless transmission line with Zo = 50
operating at 2 MHz is
terminated with a load ZL = 60 + j40 . If u = 0.6c on the line, find
(a) The load reflection coefficient ГL.
(b) The standing wave ratio.
(c) The input impedance.
Answer: (a) 0.35/56°,, (b) 2.1, (c) 23.5 + j 1.75 .
lossless line has standing wave ratio of 1.6 and θГ = 300°. If the line
3. A 70
is 0.6λ long, obtain
(a) Г0, ZL, ГL.
(b) The distance of the first minimum voltage from the load.
Answer: (a) 0.228/300°, 80.5 – j 33.6, 47.6 – j 17.5
(b) λ/6.
4. A 100 + j 150
load is connected to 75
lossless line.. if the lineis 0.6λ
long, Find:
(a) ГL.
(b) The standing wave ratio s.
(c) The load admittance YL.
(d) Zin at 0.4λ from the load.
(e) The locations of Vmax and Vmin with respect to the load.
(f) Zin at the generator.
Answer: (a) 0.66/40°, (b) 4.8, (c) 3.04 – j4. 67 mS, (d) 22.5 + j47.25
(e) 0.055λ, 0.555λ and 0.3055λ, (f) 135 – j165 .
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PHAROS UNIVERSITY
Faculty of Engineering
Subject Name: EE 262 (Microwave Engineering)
Lecturer(s): Dr. Aida EL Shafie, Eng. Heba
Electrical Engineering Department
Division of Communications & Electronics
Fall 2010
Raafat
5. On a single 50
Smith Chart, find and plot the following impedances and
find their values in normalized values and in Ohms. Also, find the reflection
coefficients at every plane. All non-labeled t-lines have zero electrical length.
Hope you the best
Dr. Aida EL Shafie
Eng. Heba Raafat
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