

Quiz 1  Transmission Line
Give the following transmission line in Figure 1 having a series inductance and resistance, and a
parallel capacitance and susceptance with the associated values. Find the total impedance (Z),
total admittance in siemens (Y), output impedance (Zo), the velocity propagation (Vp), and the
attenuation in dB/meter.
Answers:
For part 1, calculating the total impedance and admittance we take the real resistive
component (R) and add it to the imaginary component (ωL), where ω = 2 Π
Z = R + jωL = 0.25+1.256j
The admittance, Y = G + jωC = 1E6 + 628.32E6
Zo = [ Z / Y ]^{1/2}
Zo = [ (R + jωL) / (G + jωC) ]^{1/2}
Zo = 44.94  j4.39
Now, for calculating the propagation velocity;
Vp = 1 / [LC]^{1/2} = 223.61E3
Engineering key words: Line theory, transmission lines, capacitive, inductive,
resistive, susceptance, frequency, velocity factor, propagation, input and
output characteristics, attenuation, pad, dB.
