Research On Linear Frequency Modulation Interference Suppression In Meteor Burst Communications

Meteor burst communications (MBC) is a radio propagation mode that exploits the ionized trails of meteors during atmospheric entry to establish brief communications paths between radio stations up to 2250 kilometres apart. Interference suppression is always paid much attention in communication domain. Now, broadband interference suppression becomes the new focus on that driection. Fractional Fourier transform is a new time-frequency analysis tool, which is used to achieve the purpose of broadband interference suppression.In the first section, this thesis introduces the development of Meteor Burst Communication (MBC) and the properties of the meteor burst channel. In the next section, a conception of general time-frequency domain 2-Dimensional Spread Spectrum (2DSS) is introduced. The simulation result of the BER of the 2DSS communications is provided. Then, the basic mathematic theory and the characteristics of the Fractional Fourier transform are introduced. The main point of the thesis is in the forth section, it focuses on the linear frequency modulation interference suppression in 2-Dimensional Spread Spectrum system based on Fractional Fourier transform, and the improvement of this algorithm is given. Finally, the computer simulations show the advantage of the linear frequency modulation interference by the improved algorithm.