Electronic and Communication - Engineering

There are a growing number of applications worldwide that require regularly updated vehicle position and sometimes orientation. For example, applications based on in-car navigation systems require that the navigation computer knows the position of the car on the earth. In many cases, this requirement can be met by using the Global Positioning System (GPS). Although originally developed for the military, the GPS has proven to be an invaluable service for a multitude of civilian applications.

Speech security is an important aim for users of many speech communication systems. Speech scramblers are gaining widespread acceptance as a means of enhancing protection in both military and civilian applications. Therefore, there is an increasing interest in speech scramblers due to the desire for secure speech communication over existing telephone channels with standard telephone bandwidth at acceptable speech quality and reasonable cost. In this thesis, different types of scrambling systems in different domains are presented.

This thesis is concerned with the data transmission over a mobile radio channel, which is characterized a by multipath propagation with a Rayleigh fading at 900 MHz, for different Doppler frequencies. The work introduces software radio receiver design and simulation. It then attempts to develop the software radio receiver over a mobile radio channel. Many techniques were used to improve the performance of the data transmission like equalization and diversity. An adaptive equalizer is used in this work to reduce the effect of intersymbol interference (ISI).