Research On Frequency Diverse Array Radar Signal Detection Algorithm

Due to the range and angle characteristics and higher degrees of freedom caused by the small frequency increments between the array elements,the Frequency Diverse Array(FDA)radar has been widely concerned by researchers at home and abroad in recent years.In particular,given the distance-dependent characteristics,FDA have promising applications in the fields of radar jammer rejection,radio frequency stealth and target localization.At present,the FDA literature is mainly focused on parameter estimation and beamforming at the transmitting end.The application of FDA to suppress range-dimensional clutter and interference in the detection field has not been systematically discussed.Therefore,this paper focuses on the issues related to FDA detection.The main contributions of this work are summarized as follows:(1)A signal model for the FDA-MIMO radar is constructed,and the detection performance of the optimal detector for distributed source targets is analyzed.Due to the complex shape of the target,the RCS scintillations of the target will affect the detection performance.Therefore,a FDA-MIMO radar based on the distributed source model is proposed.The optimal detector for FDA-MIMO radar under the NeymanPearson(NP)criterion is derived.Furthermore,the detection performance of the FDAMIMO multi-pulse optimal detector is analyzed.Simulation results show that FDA-MIMO radar has more general adaptability,when compared with MIMO radar which requires higher signal-to-noise ratio.(2)The FDA optimal detectors based on distributed source targets are deduced.Given the insufficient detection performance of the FDA-MIMO radar at low signalto-noise ratio,a FDA radar model based on the distributed source model is derived.The single-pulse optimal detector for FDA radar is derived and the detection performance of the FDA multi-pulse optimal detector is analyzed for Swerling I and Swerling II targets.The FDA detectors have great advantages at low signal-to-noise ratio.(3)A general-purpose FDA receiving signal processing model and sufficient statistics are proposed,and then the maximum likelihood estimator and generalized likelihood ratio detector for FDA-MIMO radar and FDA radar are derived.To solve the radar detection problem of unknown targets,the maximum likelihood algorithm is applied to the universal FDA receiving model.A general-purpose FDA receiving signal processing model and sufficient statistics are proposed,and then the maximum likelihood estimator and generalized likelihood ratio detector for FDA-MIMO radar and FDA radar are derived.Simulation analysis proves that the GLRT detectors of the FDA and FDA-MIMO radar have angle-range dependence,and have higher anti-spoofing interference ability in both the range dimension and the angle dimension.