Date of Award


Document Type


Degree Name

Master of Science in Electrical Engineering


Department of Electrical and Computer Engineering

First Advisor

Richard K. Martin, PhD.


Radio Tomographic Imaging (RTI) is an emerging Device-Free Passive Localization (DFPL) technology. Radio Tomographic Imaging (RTI) involves using a set of small low cost wireless transceivers to create a Wireless Sensor Network (WSN) around an Area of Interest (AoI). Furthermore, the Received Signal Strength (RSS) between transceiver pairs is utilized to reconstruct an image from the signal attenuation caused by an object disrupting the links. This image can then be utilized for multiple applications ranging from localization to target detection and tracking. This enhances the importance of image resolution in order to capture the actual size of the objects as well as the ability to resolve multiple objects in an AoI. The objective of this research is to propose a new image formation technique for a reconstructed image within aWSN. This was accomplished using a modified Maximum Likelihood Estimate (MLE) function that forces the desired solution to be positive. Other regularization techniques must implement different methods to mitigate the undesired singular values caused from a non-invertible matrix. Additionally, the research highlights the performance of the modified MLE estimator and the robustness of improved image resolution in three different environments.

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