High Precision Portable Bioimpedance Spectrometer for Enhanced Clinical Diagnostics

Bioelectrical impedance analysis (BIA) serves as a pivotal non-invasive technique to evaluate both physiological and pathological states of human tissues. Traditional devices often fall short due to poor frequency resolution and phase accuracy, limiting their clinical utility. Addressing these deficiencies, this study introduces a portable, high-precision bioimpedance spectrometer that markedly enhances these crucial metrics. The device employs a Direct Digital Synthesis (DDS) chip, generating signals from 10 kHz to 1 MHz, and features integrated IQ demodulation paired with a 24-bit high-precision analog-to-digital converter (ADC). This setup enables the capture of detailed amplitude and phase information across a wide frequency spectrum. Augmented by a custom-designed band-pass filter and controlled via a STM32F407 microcontroller, the spectrometer improves signal quality and supports real-time data processing and interaction. Demonstrating over 95% accuracy in fixed frequency output mode, the spectrometer provides precise delineation of human tissue bioimpedance, capturing critical amplitude and phase data essential for comprehensive clinical analysis. These technological advancements not only refine the capabilities of bioimpedance measurement tools but also significantly broaden their practical applications within the healthcare sector.