Robust immune particle filter design for terrain-referenced navigation with interferometric radar altimeter

Although interferometric radar altimeter (IRA) provides accurate three-dimensional terrain information, it is difficult to eliminate some IRA uncertainties by signal processing. This calls for a filter that possesses strong robustness against outliers. An auxiliary particle filter (APF), which can be used to perform terrain referenced navigation using IRA technology as an alternative to an integrated navigation system using a global navigation satellite system, can mitigate the effect of outliers by introducing auxiliary variables. To improve APF robustness, the authors propose an immune APF, which introduces an artificial immune system to enhance outlier performance by replacing inferior particles with superior particles. The mutation process is applied to obtain particle diversity using a regularised kernel. Monte Carlo simulation results verify the robustness of the proposed filter.