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ECE 3442 Exam #1
Fall 2005
Florida Institute of Technology
Please show all work and be sure to label appropriate units on final answers.
Figure 1
1. (30 points) Figure (1) shows a lossless, 50 Ω transmission line that is terminated with an
unknown load impedance, ZL. Using the voltage pattern plotted in this figure and a
Smith chart, determine the following:
a. Wavelength on the line, λ.
b. VSWR.
c. Load impedance,ZL
2. (40 points) A lossless transmission line is 80 cm long and operates at a frequency of 600
MHz. The line parameters are L=0.25 μH/m and C=100 pF/m. Find the:
a. characteristic impedance, Zo.
b. phase constant, β.
c. phase velocity, vp.
d. input impedance for ZL=100 Ω.
3. (30 points) A lossless 75 Ω transmission line operating at wavelength λ=2cm is
terminated in a short circuit. How long should the line be in order to have an input
impedance equal to:
a. Zin = ∞
b. Zin = -j75 Ω
c. Zin = j75 Ω