Lamb Wave Communication Based on Airborne Ultrasound Excitation and Reception

Ultrasound serves as an alternative to traditional communication methods in environments with considerable electromagnetic shielding and interference. Ultrasonic-guided waves, such as Lamb waves, demonstrate advantageous transmission properties in plate-like structures, allowing for long-distance propagation with minimal energy loss. This article introduces a noncontact data transmission technique using air-coupled leaky Lamb waves. Ultrasound signals are emitted and collected by airborne ultrasound transducers. Wave conversion and the dispersion interference of Lamb waves contribute to nonlinear effects in air-coupled leaky Lamb wave communication. To address the nonlinear interference present in the received signal, the receiver uses a deep neural network for effective signal decoding. Transmission experiments in real-world conditions were performed on a plate-like structure using a pitch-catch configuration, evaluating three modulation techniques: amplitude-shift keying, frequency-shift keying, and binary phase-shift keying (BPSK). Among these methods, BPSK exhibited the most effective anti-interference performance. The actual communication system platform successfully achieved a data transmission rate of 50 kbps, with a bit error rate recorded at less than 0.2<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\%$</tex-math></inline-formula>.