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Abstract This thesis is concerned with the study of a network structure suitable for the mobile telephone networks. This structure is characterized by its hierarchical structure. transferred in the form of packets across routing of these packets is investigated. The information is this network. The The thesis consists of seven chapters, a conclusion, six appendices and a comprehensive list of references. After the introduction, which provides for the motivation and the brief description of the thesis, a tutorial chapter is presented to initiate the reader to the pertinent problematics of the telephone networks. In this chapter a software that was developed for the analysis of networks and optimum path selection, is presented. Chapter three deals with mobile communications. This chapter presents the stages of development of the mobile communication systems. A cellular network structure known as the cellular packet switch is also presented in chapter 3. The routing of the different control packets and the voice packets through this network is then considered. The fourth chapter introduces the mathematics involved into the Markov models field and the analysis of the Viterbi Algorithm. These fields have to be thoroughly investigated in order to be able to write software routines utilizing such models. The chapter may help to clarify technicalities involved. The fifth chapter introduces the ALOHA and the R-ALOHA systems. The effect of the retransmission coefficient on the performance of these systems is considered. The criteria for selecting the optimum value of the retransmission coefficient is also considered. The R-ALOHA system is analyzed using the Markov Model and the Equilibrium Point Analysis method. The range of validity of the latter method, which is an approximate method, is demonstrated The sixth chapter introduces the Packet Reservation Hultiple Access, PRMA, system. The PRMA is the transmission protocol used on the lowest level of the hierarchy in the cellular packet switch, it is used between the mobile terminal and the base station. The performance of the PRHA system is analyzed. A simulation model for the PRMA system which was built on the NETLAB to ver1fy the analytical results, is then presented. The choice of the retransmission coefficient is also considered. Finally 1n the last section of chapter six, an algorithm for determining the number of terminals in the base station region communicating through it, is developed. The performance of th1s algorithm is tested using a simulation program. Chapter seven introduces a modification of the PRMA protocol, this transmission protocol is suitable for the higher hierarchies of the Cellular Packet Switch. Two extreme cases of this transm1ssion protocol are first considered; the assigned slot access protocol and the common slot access protocol. The mixed slot access protocol which 1s a transmission protocol in between the previous protocols is then 1nvestigated to determine 1ts optimum performance. There are six appendices at the end of the thesis containing the listing of the programs used in analysis and in simulation in this thesis. |