Behavior perception-oriented convenient ultrasonic multi-channel transceiving hardware system

Abstract

A convenient ultrasonic multi-channel transceiving hardware system for behavior perception comprises a USB synchronous transceiving sound card, a platform with an operating system, an ultrasonic generation sound box and a microphone array. The USB synchronous receiving and transmitting sound card comprises an MCU, a TXCO, a USB, an audio DAC, a low-noise LDO, a microphone interface and other circuits, the sound card can be connected into the USB interface of a platform with an operating system and is recognized as USB audio playing and recording equipment, and an upper computer program controls a USB audio driver to achieve receiving and transmitting of user-defined ultrasonic signals. The ultrasonic generation sound box comprises a linear power supply, a signal impact protection and energy-saving circuit, a broadband power amplifier circuit and an aluminum strip type high pitch loudspeaker, and a sound card output signal pushes the loudspeaker to emit ultrasonic waves after power amplification of the power amplifier circuit; the microphone array is an array composed of 1-4 MEMS digital microphones capable of collecting ultrasonic frequency bands. The system is low in cost, good inuniversality and capable of being conveniently controlled, and multi-channel synchronous receiving and transmitting of any ultrasonic signals within the frequency band of 20 K-40 KHz are achieved.

Description

technical field [0001] The invention belongs to the technical field of electronic circuits and signal systems, and relates to a support platform using ultrasonic signals for application research such as behavior perception, in particular to a convenient behavior perception-oriented ultrasonic multi-channel transceiver hardware system. Background technique [0002] In recent years, a new cutting-edge research hotspot - "wireless sensing" has been born. Wireless sensing technology mainly uses pervasive wireless signals, such as RF, WiFi, ultrasonic, etc., to perceive people's non-contact behavior. These signals are not affected by light conditions. It can be applied to health monitoring, new human-computer interaction, behavior recognition, etc., and has received extensive attention and attention from academia and industry. Ultrasonic has the advantages of no radiation, easy to obtain, not affected by environmental noise, light, object color, etc., does not spy on privacy, and...

AI Technical Summary

Problems solved by technology

Commercial devices include smart mobile devices (such as PCs, smart phones, watches, etc.) and audio and microphone devices. These commercial devices generally do not directly have the ability to transmit and receive high-sampling rates and ultrasonic frequency bands. At present, the universality is not good. What can be used is the 18-22KHz frequency band. According to relevant research, some babies and children can hear ultrasound slightly higher than 20KHz. It can be seen that there is a hidden danger of interfering with children when used in the home.

According to relevant data, the hearing range of some livestock is higher than that of humans (the upper limit of hearing for cattle is about 35KHz, the upper limit of hearing for sheep is about 30KHz, and the hearing range for horses is about 25KHz), which limits the current commercial equipment that cannot be used in livestock.

In addition, these commercial devices cannot flexibly implement multiple transmissions and multiple receptions, and some even require long-term software to correct the sampling frequency offset

On the other hand, the piezoelectric ultrasonic transducers currently used based on self-made equipment can only transmit fixed frequencies, and the hardware cost for frequency modulation is very high, and even high voltage is required to drive, and the beam angle and sensitivity are small, and the sensing range is limited.

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