ACOUSTIC DATA TRANSMISSION IN AIR USING TRANSDUCER ARRAY

Acoustic data transmission is an alternative method for wireless electromagnetic communication, especially in the presence of Faraday shielding. The existing airborne acoustic wireless systems are mainly focused on short-range applications where only the direct path travelled by waves from transmitter to receiver are taken into account. However, for some applications in rooms, there would be a certain distance between the transmitter and the receiver. Reverberation plays a significant role since the sound waves can be absorbed and reflected repeatedly at boundaries like walls, floors and ceilings, etc. A novel acoustic data transmission system for anti-reverberation applications is proposed. The single-carrier frequency domain equalization algorithm is used to reduce severe inter-symbol interferences caused by reverberation. A set of transducer array is proposed to enhance the signal to noise ratio. Experiments carried out in rooms of varying sizes and reverberation times demonstrate the effectiveness of the new system.