Ultrasonic Signal Encoding and Information Transmitting

Abstract

This work deals with the practical problem of coding and control commands transmitting, as well as transmitting operating data using an ultrasonic device, which includes signal emitter and receiver. The reception scheme of low - powered signal allows extraction of information losslessly. Two ultrasonic transducers AW8T40-12OA01 and AW8R40-12OA01 (AUDIOWELL) operating at a frequency of 40.0±1.0 kHz were used as transmitter and receiver of ultrasonic vibrations. The emitter of ultrasonic radiation includes a microcontroller, a signal converter, and a transmitter. Pulses of the desired frequency are generated at the output of the microcontroller programmatically. The ultrasonic receiver includes an ULTRASONIC transducer, a two-stage amplifier, a comparator and a repeater. Transmission of values from 0 to 255 was fulfilled by using an ultrasonic signal. To simulate the process of receiving information, a switching circuit is used, in which the signal from the ultrasonic receiver is fed to the ICP input of the controller and an interrupt is used if the signal is captured. The Protocol for interaction coordination of non-volatile parts of the transceiver is developed. Two data encoding algorithms are proposed to ensure the preservation of the specified accuracy. Errors that occur during the information transmission in each case is analyzed. The ways for further development of the method and algorithm improvement are outlined. Development is carried out on the basis of the outdoor measuring complex PIKA-19, produced by LLC “Scientific and technical center PIKA-TECHNOSERVICE”.