A phase modulation-based ultrasonic communication system using Variable Structure Control

Narrow bandwidth transducers used in existing ultrasonic data communication systems are known to be devices with a high Q resonant response and low coupling to both the electrical drive and acoustic output interfaces. These features limit the speed of phase change when phase modulation (PM) is used. This paper studies the design of a Variable Structure Controller (VSC)-based transmitter with the aim of increasing the capacity of a PM-based communications system. Simulation results are presented to demonstrate the potential of this approach.