Research On Key Technologies Of Aif-earth Transmission Network

Unmanned aerial vehicle (UAV) which embodies the character of information, network, unmanned and non-contact for the future technological products represents the develop of modern technology,while it is the fast-growing field for the uav system. However, unmanned aerial vehicle is a huge system which the task of its implementation are complexity and diversity. Thus to make sure that the system of unmanned aerial vehicle can comprehensive and coordinated develop in all directions become a serious problem in the field of UAV studying. To display the advantage of UAV and avoid the disadvantage, UAV transmission network technology gradually develop into one of the important areas of UAV research.Compared to the traditional mobile communication, UAV communication link is provided with more stringent need of communication synchronization, difficulty of the rebuilding for communication channel-related data and large signal-to-noise ratio for the receiving end, while the range of visibility limits the direct communication between the UAV and the ground monitoring system.Apart from this, considering. the increasingly complex application environments and diverse needs, UAVs are subject to their own hardware and software constraints, while there are still some limitations: A single UAV is difficult to implement due to its own conditions, while it is very difficult to realize a large area coverage task area, especially when the battlefield threat is large. At last, the mission system may fail due to failure of single UAV. In order to compensate for the limitations of UAVs,unmanned aerial vehicles mission systems have emerged in the development process of formation flying group work.In this paper, on the basis of the establishment of UAV communication link models, research on the link switching mode of UAV under different flight scenarios; on the basis of the data link model,research on reasonable and effective adaptive coding modulation technology in UAV communication system; finally research on multi UAV ad hoc network task based on swarm intelligence.The main innovations and research work of this paper are as follows:(1) On the basis of studying the influence factors of UAV Communication links, considering the channel environment change of UAV in long flight mission, establish UAV communication link models in multiple scenes, simulate the various link model, based on the analysis of simulation results, research on the link selection switching strategy in long endurance and multi scenes UAV system.(2) Based on the established UAV communication link models,discuss the channel stochastic process of UAV Communication System in depth, combine the switched adaptive encoding modulation of traditional algorithm (ACM-MCS) with UAV channel, analyze the advantages and disadvantages of traditional algorithms, research on the adaptive switching algorithm based on interval statistical principle of symbolic distribution. Simulate of the proposed algorithm that based on interval statistical principle of symbolic distribution, analyze the error rate and throughput performance in UAV Communication system, verify the applicability in UAV Communication system.(3) Research on multi UAV ad hoc network task based on swarm intelligence, analysis the methods and strategies of multi UAV cooperative reconnaissance and attack target, combine the traditional ant colony algorithm and UAV task, design a parallel intelligent ant colony algorithm to solve the UAV network task problem. Simulate of parallel intelligent ant colony algorithm, verify the performance of multi UAV ad hoc network.