A method to detect delamination in a composite material, using a surface mounted fiber Bragg grating (FBG) sensor, is proposed in this paper. In this method, the static strain is measured to accurately detect the delamination area. Experiments are carried out and results show the relation between the wavelength shift and the distance between the FBG center and the delaminated area. The sensitivity of this method is also discussed. Results show the feasibility of this technique for structural health monitoring applications.
We propose in this letter a simple and cost-effective method for a bandwidth enhancement of multimode fiber (MMF) using periodic mode scrambling. Simulations and experiments were carried out to verify the feasibility of this method, and results show that the bandwidth of multimode fiber is increased by about two times. This scheme can be used to support future large-bandwidth applications by upgrading existing MMF links.