Research On Technology Against Interference Of FSK Based On SDR Platform

SDR (software defined radio) has got quiet great evolution since it was raised in the early 1990s, which is based on the theory of modern communication, with the core of digital signal processing, and supported by the technique of micro-electronic. SDR has attracted the attention of military communication, personal mobile communication, micro-electronic, computers and other electronic fields. SDR breaks the limited design that the traditional radio has a single function with badly expansibility hardware, emphasizes the characteristics of the software realization of the system functions and the modularization of the hardware, and makes it easy to update the system with less cost so as to support multiple communication standards.Based on the theory of SDR, the algorithm of demodulation of FSK signals and a universal multi-DSP platform are discussed and researched with the properties of digital signal processing in SDR receiver and characteristics of fixed-point DSP chip. The experiment on anti-interference FSK data transmission was carried out with the conventional AM/FM transceivers working on VHF/UHF band on this platform. A research on the topic was carried out deeply in the following aspects.(1) The basic concept of SDR, the motive, the significance and the internal and overseas actuality on the topic of the research was introduced.(2) The basic theory of SDR receiver and parallel processing system were introduced. It presents the related fundamental theory of the SDR receiver, including the signal sampling theory, signal processing with multiple speed, etc. and the basic concept and content of parallel processing system.(3) The algorithms of demodulation of the FSK signals and implement on DSP platform based on SDR were researched. First, the basic characteristics of the FSK signals, the receiving methods in common use and the capacity were introduced. Then, the model of the digital non-coherent demodulation of the FSK signals and the implement on DSP platform were researched emphatically.(4) The frame structure and the method of synchronization on...