Phonocardiographic Noise Suppression for Low-Cost BLE Enhanced Digital Stethoscopes

This paper presents the development of a low-cost Bluetooth ™ Low Energy (BLE) stethoscope with a novel approach for noise suppression to enhance remote healthcare applications. The proposed device combines a high-fidelity microphone with a microcontroller-based digital signal processing (DSP) unit for efficient real-time data processing. BLE connectivity is utilized to enable seamless wireless transmission of phonocardiographic data to a central device, facilitating remote patient monitoring. The stethoscope's affordability and compact, portable design make it well suited for telemedicine applications, enabling remote patient monitoring and diagnosis in areas, which are resource limited or where access to healthcare facilities may be insufficient. Additionally, the low-power design ensures an extended operationallifespan, making it suitable for home healthcare and mobile clinics. A key aspect of the presented work lies in its tailored noise suppression approach, specifically designed to improve the quality of phonocardiographic recordings. The system utilizes two microphones: one dedicated to capturing only environmental noise, and the other capturing both the main heart sound signal and background noise. By leveraging this dual-microphone setup, the system can effectively and exclusively suppress ambient noise from the recorded heart sounds, ensuring clear auscultation and enhancing diagnostic value. Experimental results demonstrate the effectiveness of the presented noise suppression algorithm by not only significantly reducing background noise, but also maintaining high signal clarity. This innovation provides a reliable, cost-effective alternative to traditional stethoscopes, promoting broader access to telemedicine solutions and improving patient outcomes in diverse clinical and non-clinical environments.