TY - JOUR T1 - A Splitting Method for Nonlinear Filtering Problems with Diffusive and Point Process Observations AU - Zhang , Fengshan AU - Zou , Yongkui AU - Chai , Shimin AU - Cao , Yanzhao JO - Communications in Computational Physics VL - 4 SP - 996 EP - 1020 PY - 2024 DA - 2024/10 SN - 36 DO - http://doi.org/10.4208/cicp.OA-2024-0075 UR - https://global-sci.org/intro/article_detail/cicp/23484.html KW - Nonlinear filtering problem, Zakai equation, splitting-up technique, error analysis. AB -

This paper aims to develop and analyze a comprehensive discretized splitting-up numerical scheme for the Zakai equation. This equation arises from a nonlinear filtering problem, where observations incorporate noise modeled by point processes and Wiener processes. Initially, we introduce a regularization parameter and employ a splitting-up approach to break down the Zakai equation into two stochastic differential equations and a partial differential equation (PDE). Subsequently, we employ a finite difference scheme for the temporal dimension and the spectral Galerkin method for the spatial dimension to achieve full discretization of these equations. This results in a numerical solution for the Zakai equation using the splitting-up technique. We demonstrate that this numerical solution converges to the exact solution with a convergence order of $\frac{1}{2}.$ Additionally, we conduct several numerical experiments to illustrate and validate our theoretical findings.