Low-frequency noise reduction by a noise barrier made of a resonator array

Noise barriers reduce the level of noise that reaches the receiver by interrupting the noise propagation path. Even though noise barriers are effective at high frequencies, low-frequency control remains challenging as sound waves at low frequencies are easily diffracted over the barriers. In this work, we show that by designing noise barriers designed with an array of tuned resonators can achieve high attenuation, more than 5 dB, of noise at low frequencies. The propagation of low-frequency waves is significantly suppressed by the interplay of the tuned resonators installed on the surface of the noise barriers. Analytical models and numerical simulations are used to calculate the insertion loss by the designed noise barriers.