High Resolution MIMO-HFSWR Radar Using Sparse Frequency Waveforms

In high frequency surface wave radar (HFSWR) applications, range and azimuth resolutions are usually limited by the bandwidth of waveforms and the physical dimension of the radar aperture, respectively. In this paper, we propose a concept of multiple-input multiple-output (MIMO) HFSWR system with widely separated antennas transmitting and receiving sparse frequency waveforms. The proposed system can overcome the conventional limitation on resolutions and obtain high resolution capability through this new configuration. Ambiguity function (AF) is derived in detail to evaluate the basic resolution performance of this proposed system. The advantages of the system of fine resolution and low peak sidelobe level (PSL) are demonstrated by the AF analysis through numerical simulations. The impacts of Doppler effect and the geometry configuration are also studied.