Marcel Nassar (The University of Texas at Austin), “Graphical Models and Message Passing Receivers for Interference Limited Communication Systems” (2013)

Marcel Nassar (The University of Texas at Austin), “Graphical Models and Message Passing Receivers for Interference Limited Communication Systems”, Advisor: Prof. Brian L. Evans (2013)

Communication performance in Wi-Fi, powerline and cellular communication systems is increasingly being limited by interference.  Interference comes from uncoordinated transmitters and switching electronics.  In unlicensed bands, interference also comes from other services operating in the same band.  This interference, which has non-Gaussian statistics, causes severe degradation in conventional communication systems that assume that noise and interference have Gaussian statistics.  This dissertation derives statistical-physical models for uncoordinated interference in powerline communication (PLC) networks. The dissertation then extends these models for wireless and powerline interference to include temporal dependence among amplitude samples. The extensions are validated with measured data.  Next, the dissertation utilizes the proposed models to design receivers in interference-limited environments by combining soft-input soft-output decoding, approximate message passing, and sparse signal recovery for joint channel/interference estimation and message decoding.  The resulting receiver designs provide significant improvements in communication performance (more than 10 dB) and map well to field-programmable gate arrays.  Finally, this dissertation designs robust receivers that can be deployed in rapidly varying environments where the interference statistics are constantly changing.

For details, please contact the author or visit the thesis page.