A convenient behavior-aware multi-channel ultrasonic transceiver hardware system

Abstract

A convenient behavior perception-oriented ultrasonic multi-channel transceiver hardware system, including USB synchronous transceiver sound card, platform with operating system, ultrasonic generator sound and microphone array; USB synchronous transceiver sound card includes MCU, TXCO, USB, audio DAC, low-noise LDO And microphone interface and other circuits, the sound card can be connected to the USB interface of the platform with the operating system, and recognized as a USB audio playback and recording device, the USB audio driver is controlled by the host computer program to realize the transmission and reception of custom ultrasonic signals; Including linear power supply, signal impact protection and energy-saving circuit, broadband power amplifier circuit and aluminum ribbon tweeter, the output signal of the sound card is amplified by the power amplifier circuit to drive the speaker to emit ultrasound; the microphone array is 1‑4 MEMS digital microphones that can collect ultrasound frequency bands composed of arrays. The system has low cost and good universality, and can be conveniently controlled to realize multi-channel synchronous transmission and reception of any ultrasonic signal in the 20K‑40KHz frequency band.

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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