A Low-Power Bluetooth LE Surface EMG Sensor

We present a low-power Bluetooth Low Energy (BLE) surface electromyography (sEMG) system designed for wearable muscle monitoring. The device integrates a fully custom signal acquisition pipeline — including analog filtering, signal conditioning, dataset-driven waveform reproduction, and BLE-based wireless transmission — centered around a ∆Σ 16-bit ADC and a Nordic nRF52840 SoC. To evaluate its performance, a representative sidekicking motion from a public sEMG dataset was physically reproduced and recorded by both the proposed system and a clinical-grade EMG device. Time and frequency domain analyses show that the system preserves the key features of myoelectric signals within the 30–400 Hz band. Results support its suitability for applications in sports science, rehabilitation, and human–machine interaction.