Dual Sensor Technology For Heart Rate Measurement

The standard method of determining heart rate (HR) involves the use of an electrocardiograph (ECG), which registers the electrical activity of the heart. While ECG is the gold standard reference to assess various cardiac parameters, it is unsuitable for daily monitoring of HR. Over the last several decades, several wearable HR monitoring devices have been developed with the intent of delivering automated, convenient, and continuous HR monitoring. A number of these technologies are wireless and based on photoplethysmography (PPG) signal assessment, which measure changes in blood volume in the microvascular tissue under the skin.

Advantages of PPG over ECG-based systems include^2,3:

• Lower costs
• Non-invasive measurement
• 24/7 monitoring in the patient’s natural environment
• Ease of physiological data collection
• Remote monitoring
• Simpler hardware implementation, increasing flexibility and mobility of users
• Single sensor requirement (vs minimum of three bioelectrodes required for effective operation of an ECG –based system)