Bo Zhang
Electrical Engineering Kansas State University
Transmission Line
Why the artifact is included:
A transmission line is a pair of electrical conductors carrying an electrical signal from one place to another. Coaxial cable and twisted pair cable are common examples. [4] It is important to study the transmission lines. For instance, we need to carry electricity wherever we want it to go. In this way, the electricity that is created in one place can be used to turn on a light many, many miles away. Besides, this task can show that I am good at PSpice simulation and I understand theories of transmission lines.
How the artifact relates to the engineering process:
Following engineering process is essential to do this project. It takes some time to know how to get bounce diagram and calculate voltage on two terminals of transmission lines, which is the first step my engineering process. Because this is not a big project, I do not need to build a model or prototype. Matching the impedance of two transmission lines requires to find some possibilities, which is important in this task.
The detailed illustrations of this practice are typed with images below.
First, I use PSpice to simulate a 5V step function source with a 25 Ohms source impedance that will drive a transmission line with Z0=75 Ohms and TD=50ns. Terminate the end of the transmission line with 1k resistor.
This is the simulating results of source, input terminal, and output terminal voltages.
Second, I use Pspice to simulate a 5V step function source with a 75 Ohms source impedence that wi;; drive two series transmission lines. The first line has Z0=75 Ohms and TD=50ns. The second line has Z0=200 Ohms and TD=50ns.
This is the simulating results of driving two transmission lines
Thirdly, I modify my simulations to model the two transmission lines with the resistive matching network.
This is the simulating results of adding a resistor network to match the two transmission lines.
[4] K. Hashemi, "Transmission Line Analysis," [Online]. Available: http://alignment.hep.brandeis.edu/Lab/XLine/XLine.html. [Accessed 4 2016].