Iterative time reversal with tunable convergence

Iterative time reversal with tunable convergence

Introduction: Spatiotemporal focusing of waves has applications in fields such as imaging and communication. Time reversal (TR) mirrors have been used to focus waves in both space and time [1]. An ideal TR mirror consists of a wave source located inside a lossless medium that is completely enclosed by a surface of transceivers, which record and absorb the signal initially broadcast by the sourc...

Iterative time reversal in the ocean

The iterative time-reversal process focusing on the strongest scatterer in a multitarget medium has been described theoretically in terms of eigenvalues and eigenvectors of a time-reversal operator K*K in ultrasonics @Prada et al., J. Acoust. Soc. Am. 97, 62–71 ~1995!#. In this paper, we extend the concept of iterative time-reversal to waveguide propagation in the ocean. For a single target, th...

Iterative time reversal based flaw identification

In the field of ultrasonic non-destructive testing, ultrasonic impulses are used to detect flaws in componentswithout causing damage. Based onperforming experiments alone, it is possible to infer the state of the component – but this usually provides only limited details about the interior damage such as its position, dimension or orientation. Furthermore, the amount of sensors that can be used...

Second Order Sliding Mode Control With Finite Time Convergence

In this paper, a new smooth second order sliding mode control is proposed. This algorithm is a modified form of Super Twisting algorithm. The Super Twisting guarantees the asymptotic stability, but the finite time stability of proposed method is proved with introducing a new particular Lyapunov function. The Proposed algorithm which is able to control nonlinear systems with matched structured u...

New family of Two-Parameters Iterative Methods for Non-Linear Equations with Fourth-Order Convergence