The paper deals with the design of a state observer for linear time-invariant systems, which converges in finitetime without resorting to high-gain injection. The devised observer is based on modulation integrals as the main enabling tool, and can be implemented as a jump-linear system. The dynamics of the state estimation error is proven to be inputto-
state stable with respect to the additive measurement noise on the system’s output. Numerical examples are included to show the effectiveness of the proposed method and to provide comparisons with some existing techniques.