Scheduling and MAC protocols for wireless networks
The design philosophy of the latest wireless networks is radically different from the traditional design philosophy. Even though the physical communication protocols have a considerable impact on the wireless system efficiency, from the system point of view, medium access control, routing, and scheduling protocols, i.e., the layer 2 and 3 protocols in the ISO protocol hierarchy, have a determining impact on the overall system performance. The purpose of this work is to propose, study and analyze various communication protocols for different wireless communication networks. ^ We consider two kinds of problems. First we study scheduling problems in wireless cellular networks. In this problem, the emphasis is on fairness and Quality of Service guarantees in an environment where the time varying channel conditions give rise to time varying data rates. We formulate different scheduling problems as constrained optimization problems and obtain optimal scheduling algorithms. These algorithms can be viewed as generalizations of the traditional opportunistic scheduling algorithms. The second class of problems that we study is the problem of Medium Access Control (MAC) in decentralized wireless local area networks in which nodes are equipped with directional antennas. We first propose a list of requirements that a good MAC protocol must satisfy and then suggest a protocol satisfying all the requirements. By analyzing and simulating the proposed MAC protocol, we demonstrate the performance advantage of the suggested protocol over other MAC protocols. ^
Major Professor: Catherine P. Rosenberg, Purdue University.
Engineering, Electronics and Electrical|Computer Science