An Optical Signal Simulator for the Characterization of Photoplethysmographic Devices

• Published in: Sensors (Basel, Switzerland) Vol. 24; no. 3; p. 1008
• Main Authors: Pittella, Erika, Testa, Orlandino, Podestà, Luca, Piuzzi, Emanuele
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 01-02-2024
• Subjects: Algorithms; Blood; Cardiovascular disease; characterization of biomedical devices; Databases, Factual; Design; Heart beat; Heart rate; Heart Rate - physiology; Light emitting diodes; Medical equipment; monitoring of vital signs; Online databases; optical signal simulator; Oxygen saturation; Photoplethysmography - instrumentation; Physiological apparatus; Physiology; Radiation; Signal Processing, Computer-Assisted; Software; characterization of biomedical devices; monitoring of vital signs; optical signal simulator
• ISSN: 1424-8220; 1424-8220
• DOI: 10.3390/s24031008

(1) Background: An optical simulator able to provide a repeatable signal with desired characteristics as an input to a photoplethysmographic (PPG) device is presented in order to compare the performance of different PPG devices and also to test the devices with PPG signals available in online databases. (2) Methods: The optical simulator consists of an electronic board containing a photodiode and LEDs at different wavelengths in order to simulate light reflected by the body; the PPG signal taken from the chosen database is reproduced by the electronic board, and the board is used to test a wearable PPG medical device in the form of earbuds. (3) Results: The PPG device response to different average and peak-to-peak signal amplitudes is shown in order to assess the device sensitivity, and the fidelity in tracking the actual heart rate is also investigated. (4) Conclusions: The developed optical simulator promises to be an affordable, flexible, and reliable solution to test PPG devices in the lab, allowing the testing of their actual performances thanks to the possibility of using PPG databases, thus gaining useful and significant information before on-the-field clinical trials.