Analysis of clutter distribution in bistatic high frequency surface wave radar

In high frequency surface wave radar (HFSWR), surface target detection is mainly limited by ocean clutter and ionospheric clutter. In order to investigate further the nature of both clutters and to develop potential strategies to enhance target detection, an experiment was conducted to operate a radar simultaneously in both monostatic (transmitter and receiver are co-located) and bistatic (transmitter and receiver are far from each other) modes. Experimental results from bistatic HFSWR are compared to those from monostatic HFSWR. It is shown that the ionospheric clutter has different distributions for the two modes. This difference may potentially be exploited to enhance the performance of the radar. A comparison between the predicted Bragg frequency and measured Bragg frequencies has been undertaken and it is shown that the Bragg frequency has a curvature along the range due to the side scattering experienced in bistatic operation.