الفهرس 
The Telephone NetworkOnly 14 pages are availabe for public view
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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.