Design and Implementation of Recording Shield System Based on STM32

In order to improve the application of privacy protection technology in audio recording field, this paper designs a recording shielding system based on STM32 single chip microcomputer. The system integrates two core modules of recording shield signal generator and audio signal recognizer to effectively shield unauthorized recording behavior. The system generates pseudo random sequence amplitude-modulated sine waves to drive the ultrasonic transducer to generate shielded signals. The system can also recognize human voice and music signal through audio acquisition and signal processing technology, and realize the shielding of music signal. The experimental results show that the system can screen recording at a distance of more than one meter and an Angle of less than 45°, and automatically identify and distinguish between human and musical signals. This paper provides a new solution for recording shielding technology, which is significant for protecting personal privacy and information security.