Weak Signal Reception Using Software Defined Radios and a Two-Element Antenna Array

Abstract

Software Defined Radio (SDR) is a quickly emerging technology. SDR removes the signal processing task from the analog hardware portion of a radio and places it into the Digital Signal Processing (DSP) domain. Many algorithms exist for removing noise from a signal and recovering the small signals inside. This thesis will explore the use of a two-element antenna array in conjunction with adaptive signal processing algorithms to not only recover small signals but reject strong interfering ones. This project is implemented using a standard desktop PC with a high performance Analog-to-Digital (A/D) card in conjunction with MATLAB software from The Mathworks, Inc. This thesis will describe the hardware used to acquire the signals, the theory of a two-element antenna array, details of the mathematical theory of the DSP process, details of the software code used to decode the signals and performance metrics of each component. Finally, the performance of the entire system will be reported as well as any future improvements that are needed.