Research And Simulation Analyisis For Sea Cluster Character Of High Frequency Radar

Sea clutter is an important interference sources for the background of sea target for HF (high-frequency) radar detection, which will lead to a specific range of HF radar blind speed. For the HF radar, sea clutter signal is a necessary subject. There is already a more mature theoretical model and in-depth study for different HF radar systems single-base-free conditions of ionosphere disturbances characteristics of sea clutter and detection of sea clutter and target signal separation methods. However, the two-base high-frequency radar and high-frequency sky-wave propagation in sea clutter radar signal processing theory and research is still in the process of gradual improvement. For the purpose of practical HF radar research, this paper provides a theoretical overview of all cases of sea clutter model and simulation analysis. The main contents are:First, using theoretical analysis of a single base from the HF radar sea scattering mechanism, its simulation and comparison results has been presented. Using mainly Barrick single base model of sea surface scattering cross section, considering the actual working environment, the analysis of radar elements of the sea surface scattering model of sea state wave height spectrum—the distribution of sea wave energy relationship with the sea breeze has been shown. Further, a variety of factors on the morphology of the sea clutter spectrum has been discussed in theoretical analysis.Second, in the main HF radar bistatic sea surface scattering situation, its simulation analysis has given. The geometric distribution of bistatic sea clutter characteristics lead to the single base is different, except bistatic radar scattering Bragg frequency outside the frequency associated with the bistatic angle is also related, according to this situation, put forward the concept of wide-beam, and conditions of wide-beam characteristics of sea clutter spectrum - broadening effect. Then we use wide beam clutter of separate processing units within the idea to approximate the conditions of narrow beam, and apply Gill's two-base narrow beam surface scattering model, are wide beam under the conditions of the sea clutter spectrum expression, and do the simulation analysis, and verify the condition of wide-beam broadening effect of the theoretical analysis.Finally, the study contains elements of ionosphere disturbances of the sea clutter signal conditions, and the removal of ionosphere disturbances Treatment. A brief analysis of the characteristics of the ionosphere and the model, and analyze high-frequency ionosphere radar echo signal for various effects - effects of multi-mode, multi-path effects, and ionosphere phase contamination. For the case of phase contamination of the signal spectrum of sea clutter wide assessment and application of the current treatment of ionosphere phase path interference more effective P & B algorithm, to remove the phase-path echo signal modulation, restore back to the spectral shape, phase-path extraction modulate curve.