Electrical and Computer Engineering ETDs

Publication Date



Current practices in geothermal research require electrical prospecting methods such as resistivity mapping and profiling. This project was predicated on the need for an improved measurement technique for performing dc resistivity mapping at the earth's surface. A synchronous detection system provides automatic detection, recording, and flexible control for the signal current source used in resistivity mapping. As a part of this project, a synchronous detection system was designed, fabricated, and tested. The system incorporates a noise suppression scheme using the frequency-modulated spectrum of the noisy signal. The overall system, which includes a Synchronous Transmitter Control, a Synchronous Detector, and a Synchronous Programmer, is shown to be a significant improvement over presently available equipment. It is capable of measuring transmitted square wave signals in a noisy environment and at considerable distances from the transmitter. The organization of the entire system, as well as the detailed operation of each of the three units are discussed. A complete set of schematic diagrams is presented along with the raw test data which compares the synchronous system with the strip chart recorders commonly used.

Document Type




Degree Name

Electrical Engineering

Level of Degree


Department Name

Electrical and Computer Engineering

First Committee Member (Chair)

Ahmed Erteza

Second Committee Member

Ruben David Kelly

Third Committee Member

Roy Arthur Colclaser