Polarimetric statistical MIMO radar for target detection based on quaternion technique

Quaternion technique is applied to model the polarimetric statistical MIMO radar system, where electromagnetic vector sensors are employed at each receiver to exploit polarization information of reflected signal. Based on the refined quaternion model, quaternion adaptive detector and its complex counterpart are compared and analyzed. The quaternion adaptive detector outperforms its complex counterpart. The improved performance derives from the better estimate of noise covariance matrix. Further, the accuracy of the estimate is evaluated by Kullback-Leibler (KL) divergence method which can justly compare the quaternion and complex estimates by information entropy. The results are also validated by several numerical simulations.