COLLABORATIVE DECODING AND ITS PERFORMANCE ANALYSIS By XIN LI A DISSERTATION PRESENTED TO THE GRADUATE SCHOOL OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY

of Dissertation Presented to the Graduate School of the University of Florida in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy COLLABORATIVE DECODING AND ITS PERFORMANCE ANALYSIS By Xin Li May 2006 Chair: Tan F. Wong Major Department: Electrical and Computer Engineering Antenna array processing is a common technique that utilizes spatial diversity to enhance the robustness of a digital communication system against deteriorative wireless transmission effects such as channel noise and fading. In order to obtain spacial diversity effectively, the physically connected antenna array elements in a traditional array are required to be separated far apart so that the received signals at different antennas are independent of each other. This situation usually makes the size of the antenna array too large to be feasible in many practical scenarios. Unlike traditional arrays, distributed arrays alleviate the array size constraint by utilizing a cluster of independent physically separated receivers in a wireless network as its array elements. All the array elements (receiving nodes) can communicate with each other through a wireless broadcast channel. By exchanging information among these receiving nodes during the reception process, it is possible to obtain spatial diversity gain (or antenna gain) with such a distributed array. Since the information exchanging traffic load among the receiving nodes is an important issue for a wireless network, conventional receive diversity techniques such as maximum ratio combining (MRC) become inefficient in distributed arrays.