# Calculate the reflection coefficients of the load and the source impedances

Hi there,
I am new member to this forum.
I am taking online courses, in order to get my degree.

For all of the problems, the transmission line in the problem has a characteristic impedance of 50 ohms and is one quarter wavelength (an electrical length of 90 degrees) at the frequency of the source.

Likewise for all problems, the source voltage is a 1.0 volt peak sine wave. However, note that the source impedance varies from problem to problem.

1a. Calculate the reflection coefficients of the load and the source impedances if the load impedance is 75 ohms and the source impedance is 25 ohms.

1b. Calculate the peak voltage at the load and the peak voltage at the input of the transmission line.

2. Repeat problem 1 for a load impedance of 50 ohms and a source impedance of 75 ohms.

3. Repeat problem 1 for a load impedance of 25 ohms and a source impedance of 50 ohms.

4. A 75 cm length of coaxial transmission line has a characteristic impedance of 50 ohms. The capacitance per unit length of the line is 1pf/cm.

a. Calculate the inductance per unit length.
b. Determine the relative dielectric constant of the material separating the inner conductor from the outer conductor.

5. The reflection coefficient of a load is 0.5+j.5
a. Plot the location of the reflection coefficient on the complex plane.
b. Plot the location of the complex conjugate of the reflection coefficient on the complex plane.
c. What is the reflection coefficient seen at the input of a transmission line connected to this load if the line is 90 degrees long (quarter wavelength).

Thanks
Battal H. Al-Qahtani

Welcome to the Forum.

The forum rules is that you have to show you assumptions and workings before we help you.
Check the rules on the Homework section it will give a proformer.

Trying not to be patronising, but if we just give you the answer you won't learn how to do it.

berkeman
Mentor
Moved to Homework Help forums. And as Panda says, you need to show us your attempts at the solutions before we can offer out help, Battal.