Enhancement of asymmetric acoustic transmission based on a plate with periodic stepped resonators

A steel plate with periodic stepped resonators immersed in water has been presented to enhance the asymmetric acoustic transmission (AAT) in the present paper. It results from the re-emitted waves at resonance by the cap which would act as a secondary source. By changing the geometrical parameters of the stepped resonator, the AAT phenomenon can be tuned easily. The proposed acoustic system may have potential impact on underwater. acoustic and medical ultrasonic devices in sub-wavelength region.