Electrical & Computer Engineering, Department of


Date of this Version

Summer 6-15-2011


A THESIS Presented to the Faculty of The Graduate College at the University of Nebraska In Partial Fulfillment of Requirements For the Degree of Master of Science, Major: Telecommunications Engineering, Under the Supervision of Professor Hamid Sharif. Lincoln, Nebraska: April, 2011

Copyright 2011 Nicholas W. Scott


This thesis studies techniques for detecting cellular phones. It examines existing technology currently available on the open market, an existing design that utilizes mostly discrete components, and a design approach using a down converter in conjunction with a bandpass filter.

The existing technologies available on the open market are examined and discussed. These technologies are not adequate, because they are inaccurate and expensive.

The first signal detection technique, an existing design utilizing discrete components is difficult to implement. They are very affordable to construct, but require precision tuning. This design is analyzed and found to be inaccurate.

The second signal detection technique, a design using a down converter, voltage controlled oscillator (VCO), and a bandpass filter was investigated for cellular phone detection. The performance of this technique through hardware and computer modeling is discussed and the results are presented. The new system is accurate and a practical solution for detecting cellular phones in a secure facility.