Adaptive Detection Schemes for Multistatic/Polarimetric Radar Networks

This paper addresses the design of bespoke adaptive detectors for point-like targets embedded in a sea-clutter-dominated environment using a multistatic/polarimetric radar network. The system consists of one monostatic as well as two co-located and cross-polarized bistatic sensors. The detector design accounts for possible range domain heterogeneity in sea-clutter backscattering, as well as potential functional relationships between the covariance matrices that characterize clutter returns across the bistatic polarimetric nodes. Accordingly, suitable estimates of the nuisance parameters for both monostatic and bistatic measurements are employed to develop adaptive decision rules based on the two-step Generalized Likelihood Ratio Test (GLRT) design criterion. The performance of the proposed receivers is assessed using simultaneously recorded monostatic and cross-polarized bistatic returns collected with the Netted RADar (NetRAD) system. The analysis assesses both the Constant False Alarm Rate (CFAR) behavior and the detection capability. The results show that, despite minor deviations from ideal CFAR behavior when near zero Doppler cells are tested, all the proposed decision rules maintain an overall robust CFAR behavior with respect to the nuisance parameters. In terms of detection capability, the proposed strategies outperform those relying solely on monostatic measurements and demonstrate comparable, or slightly improved, performance with respect to a competing approach confirming the effectiveness and robustness of the devised techniques.