“…There are two frameworks available to solve this problem including the decorrelating framework (Bar-Shalom, Li, & Kirubarajan, 2001) and Gaussian approximation recursive filter (GASF) framework (Wang, Liang, Pan, & Yang, 2012). For linear Gaussian system, these two frameworks are completely equivalent (Chang, 2014a), and for general nonlinear system, they are equivalent in the linear minimum mean square error (MMSE) sense (Wang, Liang, Pan, & Wang, 2014).…”