**3. Simulation Analysis of the First-Order Sea Clutter Spectrum for a Coast–Ship Bistatic HFSWR**

As can be seen from the above, the Doppler shift of both the first-order sea clutter spectrum and the moving target echo were affected by the radar frequency, bistatic angle, and velocity of the shipborne platform. To quantitatively analyze the characteristics of the broadening of the sea clutter spectrum and the related blind area, simulation analysis of the first-order sea clutter spectrum for a coast–ship bistatic HFSWR was studied under conditions of different frequencies, different platform velocities, and different elliptical rates. In the following simulation, it was assumed that heading of the shipborne platform was consistent with the navigation direction.

It must be highlighted that the focus of this paper was on the application of bistatic radar target monitoring. For this reason, the Doppler shift of the first-order sea clutter spectrum and the related influence on the blind area are expressed with base units of velocity magnitude (i.e., m) instead of Hz. In addition, as CTSR and STCR are equivalent bistatic configurations when similar antennas and array configurations are used, the simulation results and influence analysis of only the CTSR bistatic radar system are presented here. Simulation results for the STCR bistatic radar system could be obtained by replacing the velocity of the receiving station platform with that of the transmitting station platform.
