Source and Channel Coding Strategies for Wireless Sensor Networks

Source and Channel Coding Strategies for Wireless Sensor Networks

Date: December 2012
Creator: Li, Li
Description: In this dissertation, I focus on source coding techniques as well as channel coding techniques. I addressed the challenges in WSN by developing (1) a new source coding strategy for erasure channels that has better distortion performance compared to MDC; (2) a new cooperative channel coding strategy for multiple access channels that has better channel outage performances compared to MIMO; (3) a new source-channel cooperation strategy to accomplish source-to-fusion center communication that reduces system distortion and improves outage performance. First, I draw a parallel between the 2x2 MDC scheme and the Alamouti's space time block coding (STBC) scheme and observe the commonality in their mathematical models. This commonality allows us to observe the duality between the two diversity techniques. Making use of this duality, I develop an MDC scheme with pairwise complex correlating transform. Theoretically, I show that MDC scheme results in: 1) complete elimination of the estimation error when only one descriptor is received; 2) greater efficiency in recovering the stronger descriptor (with larger variance) from the weaker descriptor; and 3) improved performance in terms of minimized distortion as the quantization error gets reduced. Experiments are also performed on real images to demonstrate these benefits. Second, I present a ...
Contributing Partner: UNT Libraries
Comparison of source diversity and channel diversity methods on symmetric and fading channels.

Comparison of source diversity and channel diversity methods on symmetric and fading channels.

Date: August 2009
Creator: Li, Li
Description: Channel diversity techniques are effective ways to combat channel fading and noise in communication systems. In this thesis, I compare the performance of source and channel diversity techniques on fading and symmetric continuous channels. My experiments suggest that when SNR is low, channel diversity performs better, and when SNR is high, source diversity shows better performance than channel diversity.
Contributing Partner: UNT Libraries
Applications of Logic Flowcharting With a Focus in Autonomous Robotic Operations

Applications of Logic Flowcharting With a Focus in Autonomous Robotic Operations

Date: 2012
Creator: Sink, Ashley Elizabeth; Gscheidle, Karl H.; Namuduri, Kamesh; Li, Li & Sterling, Phillip
Description: This report discusses research on applications of logic flowcharting with a focus in autonomous robotic operations. This research project is part of Research Experiences for Teachers (RET) in Sensor Networks, a National Science Foundation (NSF) funded grant project.
Contributing Partner: UNT College of Engineering
Applications of Logic Flowcharting With a Focus in Autonomous Robotic Operations

Applications of Logic Flowcharting With a Focus in Autonomous Robotic Operations

Date: 2012
Creator: Sink, Ashley Elizabeth; Gscheidle, Karl H.; Namuduri, Kamesh; Li, Li & Sterling, Phillip
Description: This poster discusses research on applications of logic flowcharting with a focus in autonomous robotic operations.
Contributing Partner: UNT College of Engineering