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In narrow-band digital mobile communications, an adaptive equaliser is used to cancel intersymbol interference caused by a linear dispersive channel in the pres-ence of noise. The research into an effective equalisation structure and adaptive algorithms for fading environments is increasingly popular over the past years. Master of Engineering

This thesis is primarily concerned with dynamic channel assignment (DCA) algorithms in mobile cellular communication systems. Through a study on the analytical model of Maximum Packing (MP), the blocking performance bounds for the traffic-adaptive class of DCA algorithms are derived. The main contribution of this thesis is a new distributed DCA scheme (DDCA), which attempts to optimize the co-channel reuse patterns and to combine the advantages of aggressive and timid DCA schemes. The new DDCA is compared with the lower bounds derived from MP model and other schemes. DDCA algorithm and MP model are further extended to incorporate the handoff issue, which is an important factor in cellular systems. Both the prioritized and the non-prioritized handoff procedures are investigated, respectively. Computer simulation and theoretical calculation show that the blocking performance of the proposed DDCA is slightly inferior to the optimum bounds of MP, but much better than fixed channel assignment (FCA) and hybrid channel assignment (HCA) schemes. However, this slight degradation in performance is a trade-off for less complexity in practical implementation. Master of Engineering

For Broadband ISDN (Integrated Services Digital Network), the problem of mixed and bursty traffic sources have prompted many research topics into flow and congestion controls. Several authors suggested different flow control schemes in order to make the network satisfy the user requirements for communication quality. Some authors use theoretical analytical approaches to analyse the effect of each scheme on the performance of the network. For this project, we develop a discrete event simulation to model the flow control of Asynchronous Transfer Mode (ATM) networks. Our computer simulation results in the case studies of various control schemes were compared with the results derived by the analytical results. Master of Science (Communications and Computer Networking)

Internetworking allows several different kinds of devices to participate in the network. The components (the hosts, routers, and media devices) usually are multi-vendor and heterogeneous in nature. A network management technology specific to a particular vendor is unusable in today's environment. An "open" network management technology must be used to manage the network. Master of Science (Communications and Computer Networking)

A new policing method, leaky bucket scheme, is proposed to monitor and control user traffic in an ATM network. By simulation, the effect of this new multilevel control leaky bucket scheme is studied, evaluated and compared to the conventional leaky bucket scheme in terms of average cell inter-departure time, cell delay, burstiness of traffic at the output of the leaky bucket and the potential cell loss rate when the spacing defined in the spacer and the token generation rate are changed. Master of Science (Communication and Network Systems)