Output Feedback Stabilization Using Small-Gain Method and Reduced-Order Observer for Stochastic Nonlinear Systems

This technical note further investigates more general stochastic nonlinear systems with stochastic integral input-to-state stability (SiISS) inverse dynamics and focuses on solving the following problems: 1) a class of counterexamples which are different from that in are reconstructed to discuss the relationship between two small-gain type conditions on SiISS and 2) under the weaker conditions on nonlinearities, based on a reduced-order observer, small-gain type condition on SiISS and stochastic LaSalle theorem, an output feedback controller is constructed to guarantee the global asymptotical stability in probability of the closed-loop stochastic system.