A Microcomputer-Based Interactive Transmission Line Simulator

Abstract

An interactive distortionless transmission line simulator, capable of providing dynamic oscilloscope displays of voltage and current waveforms along the line, has been implemented on an Intel 8086 based single-board microcomputer. The simulator helps the student grasp the fundamentals of transmission line behavior through the observation of transient and steady-state wave phenomena under various conditions. The user sets up a simulation by specifying the normalized line parameters, terminating resistors, and type of source. The simulator prompts the user with a mnemonic and defaul value for each parameter. A set of control commands provides a means offreezing the traveling waves, changing terminations, scaling the display, and single stepping the simulation. The simulator is easy to use, inexpensive, requires minimum hardware, and facilitates quantitative measurements on the oscilloscope. The numerical algorithm implemented on the 8036 provides a stable accurate simulation in almost all cases.