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Controlling a formation of unmanned autonomous vehicles is a daunting prospect even when the formation operates under ideal conditions. When communication between vehicles is limited, maintaining a formation becomes difficult. In some cases the formation may become unstable. While a control law may stabilize a formation of vehicles with good communication, it may not be able to do so with poor communication. The resulting lack of formation stability affects the level of ï¬ delity the formation has to the original control law. Formation ï¬ delity is the degree to which the vehicles in a formation follow the trajectories prescribed by a control law. Many formation control laws assume certain conditions. Perfect formation ï¬ delity is not guaranteed when the vehicles in a formation are no longer operated under those conditions. We seek to mitigate the detrimental effects of poor communication and other real-world phenomena on formation ï¬ delity. Through simulation we test the effectiveness of a new way to implement an existing formation control law. Real-world conditions such as rigid-body motion, swarm dynamics, poor communication, and other phenomena are assessed and discussed. It is concluded through testing in simulation that it is possible to control a formation of boats by directing each boat with a unique set of waypoints in simulation. While these waypoints do not lead to perfect formation behavior, testing shows that implementing this control law using these waypoints allows the formation to be more robust to reduced communication. / Master of Science

Cooperative relay systems have emerged as promising techniques to boost the performance of wireless systems. Recent studies have confirmed that interferences, co-channel interferences (CCIs) and self-interferences, have a huge impact on cooperative relay systems and can cause significant performance degradation. Two problems were observed in this research. Firstly, previous studies on performance analysis of Amplify-and-Forward (AF) relay systems in presence of CCIs have only focused on a specific interference channel model. However, in practical design scenarios, such an assumption is not a realistic proposition. Secondly, analyses of overheads introduced by a time-based relay selection protocol in distributed cooperative systems have been based on an over-pessimistic assumption where all packets involved in a collision are destroyed. Nevertheless, collisions due to the protocol overheads cause the system performance to be degraded but this does not mean that the failure of end-to-end transmission certainly occurs. The thesis aims to analyse the performance of practical cooperative relay systems in the presence of CCIs and self-interferences, by developing exact mathematical methods. A new unified mathematical method for AF relay systems in presence of a random number of arbitrary non-identical CCIs was developed. The obtained new approach derived in terms of a moment generating function of the aggregate interferences' power led to the derivation of new explicit expressions. The new results greatly simplify evaluation of average error rates over diverse practical interference scenarios. Moreover, a new exact mathematical analysis for distributed cooperative relay systems employing a time-based relay selection protocol based on an accurate interference model was presented. This approach led to the derivation of new exact expressions for the spectral efficiency which accounts for both self-interferences and the protocol overheads as well as for different fading scenarios and arbitrary relay locations. This approach provided several advantages over direct approaches, one of which is that it significantly simplified averaging-out the joint random variables involved.