Multicarrier Airborne Ultrasound Transmission With Piezoelectric Transducers

作者：Ens Alexander^*; Reindl Leonhard M

来源：IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, 2015, 62(5): 905-914.

DOI：10.1109/TUFFC.2014.006803

In decentralized localization systems, the received signal has to be assigned to the sender. Therefore, long-range airborne ultrasound communication enables the transmission of an identifier of the sender within the ultrasound signal to the receiver. Further, in areas with high electromagnetic noise or electromagnetic free areas, ultrasound communication is an alternative. Using code division multiple access (CDMA) to transmit data is ineffective in rooms due to high echo amplitudes. Further, piezoelectric transducers generate a narrow-band ultrasound signal, which limits the data rate. This work shows the use of multiple carrier frequencies in orthogonal frequency division multiplex (OFDM) and differential quadrature phase shift keying modulation with narrow-band piezoelectric devices to achieve a packet length of 2.1 ms. Moreover, the adapted channel coding increases data rate by correcting transmission errors. As a result, a 2-carrier ultrasound transmission system on an embedded system achieves a data rate of approximately 5.7 kBaud. Within the presented work, a transmission range up to 18 m with a packet error rate (PER) of 13% at 10-V supply voltage is reported. In addition, the transmission works up to 22 m with a PER of 85%. Moreover, this paper shows the accuracy of the frame synchronization over the distance. Consequently, the system achieves a standard deviation of 14 mu s for ranges up to 10 m.

• 出版日期2015-5