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Title: Study of dynamic frequency assignment for mobile radio systems
Author: Craine, J. F.
Awarding Body: University College of Swansea
Current Institution: Swansea University
Date of Award: 1981
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The growth of mobile radio over the last few decades has necessitated a corresponding increase in channel numbers, but more sophisticated schemes are now needed to improve the use made of each channel. This thesis investigates the problems expected in the implementation of systems in which a common pool of channels is shared by many users, each of whom is assigned a channel automatically when one is required. It is shown that a decisive factor in system performance is the amount of information which can be handled in the control channel. This is determined by the random nature of the calls and the error rate associated with the signal path. Binary signalling is found to have advantages over audio tones, due to their ease of generation and detection in large-scale integrated circuits. However, calculation shows that the rapid decrease in binary error rate above a signal-to-noise threshold is much less pronounced when even a relatively small proportion of the received signal is subject to fading. Various schemes are investigated to reduce the incidence and effects of these errors by introducing redundancy into the signals used, and employing diversity reception and error correction. The additional functions required in the fixed and mobile parts of the system are examined, especially the control, data handling, and frequency synthesis requirements. Finally, some fading simulation techniques are investigated and a real-time computer program is described which can simulate the different data transmission, reception, and processing operations needed in the system.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID:  DOI: Not available