This work relates to the quality of the electrocardiogram (ECG) signal of an elderly person, transmitted using optical wireless links. The studied system uses infrared signals between an optical transmitter located on the person’s wrist and optical receivers placed on the ceiling. As the elderly person moves inside a room, the optical channel is time-varying, affecting the received ECG signal. To assess the ECG quality, we use specific signal quality indexes (SQIs), allowing the evaluation of the spectral and statistical characteristics of the signal. Our main contribution is studying how the SQIs behave according to the optical transmission performance and the studied context in order to determine the conditions required to obtain excellent quality indexes. The approach is based on the simulation of the whole chain, from the raw ECG to the extraction process after transmission until the evaluation of SQIs. This technique was developed considering optical channel modeling, including the mobility of the elderly. The obtained results show the potential of optical wireless communication technologies for reliable ECG monitoring in such a context. It has been observed that excellent ECG quality can be obtained with a minimum SNR of 11 dB for on–off keying modulation.
11 July 2022 in Annual International Conference of the IEEE Engineering in Medicine and Biology Society
Existing Electrocardiogram (ECG) systems are either wired or based on radiofrequency (RF) wireless devices when remote transmission is needed. However, the use of radiofrequencies has limitations especially for sensitive populations such as newborns and infants. In addition, due to electromagnetic interference problems, impairments in the RF transmission of the ECG signal can lead to diagnostic errors. To answer these problems, we propose in this article, an optical wireless monitoring system, using an infrared link between an ECG sensor placed on a baby's chest and receivers placed on the ceiling of a pediatric room. In addition, it is assumed that the infant can move around in his bed. Our main contribution is the evaluation of the quality of the ECG signal transmitted by the proposed system, in terms of classic Signal to Noise Ratio (SNR) and Bit Error Rate (BER) metrics but also in terms of Signal Quality Indexes (SQIs) calculated from the characteristics of the received ECG signal. Results show the ability to perform wireless infant ECG monitoring using the Optical Wireless Communication (OWC) with satisfactory quality for optimum power.
In this work, we investigate the quality of heart rate variability (HRV) features extracted from electrocardiogram (ECG) signals transmitted by optical wireless communication (OWC). The proposed solution exploits infrared links between a transmitter placed on the chest of a newborn lying in a closed incubator and optical receivers installed on the ceiling of a neonatal intensive care unit. The specific environment and the corresponding transmission channel were modeled and simulated using the ray-tracing Monte Carlotechnique. Temporal HRV parameters were determined using the Pan-Tompkins algorithm and analyzed as a function of emitted optical power. The results obtained show that it is possible to guarantee good HRV measurements from ECG signals transmitted by OWC in the proposed context. An excellent quality of the HRV parameters could be obtained with an emitted optical power of [2.8-4.1] mW for the OOK modulation.