A Prototype of Reflection Pulse Oximeter Designed for Mobile Healthcare.

This paper introduces a pulse oximeter prototype designed for mobile healthcare. In this prototype, a reflection pulse oximeter is embedded into the back cover of a smart handheld device to offer the convenient measurement of both heart rate (HR) and SpO2 (estimation of arterial oxygen saturation) for home or mobile applications. Novel and miniaturized circuit modules including a chopper network and a filtering amplifier were designed to overcome the influence of ambient light and interferences that are caused by embedding the sensor into a flat cover. A method based on adaptive trough detection for improved HR and SpO2 estimation is proposed with appropriate simplification for its implementation on mobile devices. A fast and effective photoplethysmogram validation scheme is also proposed. Clinical experiments have been carried out to calibrate and test our oximeter. Our prototype oximeter can achieve comparable performance to a clinical oximeter with no significant difference revealed by paired t -tests ( p = 0.182 for SpO2 measurement and p = 0.496 for HR measurement). The design of this pulse oximeter will facilitate fast and convenient measurement of SpO2 for mobile healthcare.

[Development of skin moisture and body fat measurement system for mobile application].

Integrating physiological parameters measurement into mobile devices is a development tendency of mobile healthcare. Measurement methods for skin moisture and body fat content are studied in this paper. Electrodes are designed for easy integration into mobile devices, and can be embedded in the cover of the mobile phone. Experiments were conducted to obtain a fast and easy measurement method. The results of evaluation show that the measurement system can achieve the same accuracy as commercial products (with correlation above 0.9 and root mean squared error below 4%) in skin moisture and body fat content measurement. Measurement of local-area body fat content showed a nearly linear positive correlation between local-area body fat content and local-area body impedance.