Figure 4
From: Acoustic waveguide with virtual soft boundary based on metamaterials
The numerical simulation and experimental results of the VSB waveguide. (a) The speaker emits 4550 Hz acoustic waves, the symmetrical wave propagates to the right along a given channel. (b,c) give the results for 6500 Hz and 9550 Hz, respectively. (d) Antisymmetric propagating wave is created by exciting the two speaker with opposite phase signal, and it propagates alone the established channel.
