Simulation analysis and experimentation study on sea clutter spectrum for high-frequency hybrid sky-surface wave propagation mode

This study simulated the broadening first-order sea clutter spectrum and analysed the influence of ionosphere and bistatic angle on sea clutter spectrum for high-frequency (HF) hybrid sky-surface wave radar based on the mechanism of sea clutter broadening. Firstly, according to the propagation characteristics of HF waves in the ionosphere and the mechanism of the ionosphere contamination, a method of dynamic ionospheric phase contamination simulation is introduced. Secondly, the formula of the Bragg frequency of first-order sea clutter is presented derived from the system configuration, and a simulation method of broadening sea clutter is given. The influence of bistatic angle and different ionosphere state on the first-order sea clutter spectrum is further analysed. Finally, the results of theoretic analysis are examined with the experimental results based on the newly developed integrated HF sky-surface wave radar experimental system, and the dominant factor of sea clutter broadening is studied. Simulation results show that the results of experiment consist with that of theoretic analysis, simulated broadening sea clutter can better describe the characteristics of measured sea clutter.