A Time Domain Reflectometer Using a Semiautomatic Network Analyzer and the Fast Fourier Transform

A time domain reflectometer system is simulated by measuring the reflection coefficient in the frequency domain and then computing the time domain signal by the Fourier transform. The program has been written for the Hewlett-Packard 8409A Semiautomatic Network Analyzer. The computation time has been minimized by using the fast Fourier transform. The problems imposed by the difficulty of switching the HP 8409A between low- and high-frequency ranges are also discussed.