DESIGN OF NOISE-RESISTANT SIGNAL CONDITIONING CIRCUITS FOR BIOMEDICAL SENSOR APPLICATIONS

Abstract

Accurate biomedical sensor measurements are essential for reliable health monitoring, diagnosis, and patient care. However, biomedical signals such as ECG, EMG, EEG, temperature, and pulse-related signals are often weak and highly sensitive to external noise, motion artifacts, electromagnetic interference, and power supply fluctuations. This paper presents the design of a noise-resistant signal conditioning circuit aimed at improving the quality and accuracy of biomedical sensor measurements. The proposed circuit integrates low-noise amplification, filtering, impedance matching, and common-mode noise rejection to enhance weak sensor signals before analog-to-digital conversion. The design focuses on improving signal-to-noise ratio, reducing measurement error, maintaining stable frequency response, and supporting low-power operation suitable for portable biomedical devices. Results indicate that the proposed signal conditioning circuit significantly reduces noise interference while preserving the useful biomedical signal components. The circuit also improves measurement accuracy, response stability, and reliability under varying noise conditions. These findings show that a well-designed signal conditioning stage can play an important role in improving biomedical sensor performance, especially in wearable, remote monitoring, and clinical measurement applications.