m. The fast Fourier transform. Linear time- 10 Signals and noise invariant digital systems. The inverse z-transform. Data truncation. Definition of a signal. Waveform and frequency. Digital signals. Conclusions. References. Examples of signals. Classification of signals. Signal repre- sentation. Distortion of signals. Types of noise. Noise units and 3 Queuing theory measurements. Signal to noise ratio. Noise factor. Noise wave- Introduction. Models based on the exponential, Markov process and forms. Markov chains. Transform methods. Queuing networks. Queueing models for multi-access channels. References. Part 3 - Communications 4 Information theory fundamentals Introduction. Information capacity of a store. Information and ther- modynamics. Mutual and self information. Discrete memoryless channels. Discrete channels with memory. Continuous channels. 11 The telecommunications industry References. Introduction. The telecommunication model. The key players. Economic considerations. Services and technology. References. Part 2 - Physical phenomena 12 Open systems interconnection reference model 5 Teletraffic theory Introduction. OSI environment. Layered architecture. Additional Introduction. Single link models. Network models. Dynamic rou- layer elements. Specific OSI layers. Additional provisions. Conclu- teing strategies. Bibliography. sions. Appendix. 6 Electromagnetic waves 13 Multiple access techniques Principles. Generation of the electromagnetic wave. Reception of Introduction. Queuing theory. Performance parameters. Classifica- the electromagnetic wave. The space wave. The sky wave. The tion of multiple access techniques. Pure contention systems. Con- surface wave. References. tention minimisation systems. Non-contention systems. References. Contents 14 Coding 24 Telecommunication power systems The need for error control coding. Principles of ECC. Block coding. Introduction. A.C. systems. D.C. systems. Battery systems. Power Interleaved and concatenated codes. Cyclic codes. Convolution supply distribution. Pow