الفهرس 
Chapter 1 IntroductionOnly 14 pages are availabe for public view
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Abstract
This thesis is concerned with helicopter Satellite Communication (SATCOM) techniques. The objectives of the thesis can be summarized as follows: Overview of the aeronautical satellites and communication system. Introduction and investigation for a previous work of the pre- detection time diversity system and the automatic frequency control (AFC) for helicopter satellite communication. Proposal of a hybrid modulation scheme for periodic blockage cancellation and enhance the bit error rate performance. A proposed AFC which reduces the acquisition time instead of the conventional AFC. Analytical study for the conventional time diversity and the proposed hybrid modulation technique. Hence this analysis and derivation can be considered as a theoretical platform for future application. Proposal of chaotic interleaving scheme with Hybrid modulation system is performed to enhance the BER performance.
2
Study the effect of propagation fading channel on BER performance from the helicopter-to-satellite (uplink). And from the helicopter-to- earth station (downlink). The thesis is organized into seven chapters as follows: Chapter 1 gives the motivations, and the organization of the thesis. Chapter 2 describes the basic principles of aeronautical satellite systems such as satellite orbits, INMARSAT satellite, and IRIDIUM satellite. Chapter 3 gives an overview of the aeronautical communication systems as HF system, VHF system, SELCAL system and SATCOM system. Chapter 4 introduces a pre-detection time diversity scheme with accurate AFC, and a proposed mathematical platform for (H-SATCOM). Chapter 5 proposes a Hybrid modulation scheme for periodic blockage in helicopter satellite communication. Chapter 6 the proposed Hybrid modulation with chaotic interleaving technique and the effect of propagation fading channel are given. Chapter 7 gives the concluding remarks of the thesis, and provides suggestions for future research.