The next generation of communication satellites are expected to employ satellite switched multiple spot beams to increase the system capacity. In this Thesis we study two basic problems encountered in the design of a satellite switched multibeam system, in packed switching environment and with "burty" traffic. First is the switching problem from various source to destination spot beams and second is the multiple access problem between the ground stations or users within each beam.; The switching problem is studied extensively in chapters 1 and 2. There we assumed the multiple access problem solved on demand basis, forming a set of requests to be switched, called Traffic Matrix T. In chapter 1 we propose and evaluate two scheduling algorithms, which will optimally switch the traffic of the matrix T, in the sense of maximizing transponder utilization. In addition the algorithms have certain other improved characteristics such as, both generate small number of switching modes and their overall computational complexity has been reduced. The first algorithm utilizes the idea of Latin Squares, while in the second one a new approach of the problem has been introduced, the approach of transmitting simultaneously and independently "nonconflicting" submatrices of the traffic matrix.; In chapter 2 we basically, present two methods of minimizing the number of switchings while keeping the transmission time of the traffic matrix as small as possible. The first is the method of superimposing a latin square on the traffic matrix T and transmitting T according to the latin square. This method has been implemented by an efficient and optimum algorithm. A suboptimum algorithm has also been used in this case. The second is the method of "nonconflicting" submatrices used in chapter 1, which is the most appropriate for this type of problem and may be considered as an extention of the first one. Both of the above methods also permit continuous transmission of the message (a number of packets) represented by each entry in the traffic matrix. Simulations have been conducted to examine and compare the transmission time of the traffic matrix. (Abstract shortened with permission of author.)
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