MSc thesis project proposal

[2021] In-ear Heart Rate detection in a custom-fit headset. [with DOPPLE] [Already taken]

Project outside the university

DOPPLE is a Dutch company developing and producing audio systems for the professional market.

New wireless headsets, that combine audio applications (music/voice calls) with sensor applications are entering the market. Integration with new sensors in custom-fit headsets (figure) provides new opportunities in medical, fitness and home care applications. These headsets communicate with the smartphones via Bluetooth, revealing all kinds of information about the user. For the use of these headsets in fitness and health applications, an efficient heartbeat sensor is very attractive. non-contact Infrared temperature measurement in the ear canal is a convenient method to measure heart rate, however several issues need to be resolved for better accuracy. Infrared detection of the very small temperature changes (typically around 0.020 degC) due to the blood flow in the microvascular tissue in the ear is still quite a challenge.


Main challenges of the project are: Sensor and electronics have to be optimized for highest signal-to-noise ratio. 1. Determining the position in the custom-fit earbud where the thermal signal is highest. 2. Selecting a small (SMD) and sensitive infrared detector. 3. Designing a low drift, ultralow noise frontend amplifier for the detector. 4. Use of a low-power microcontroller to send the data for further processing


1. Building and testing a prototype of a heart rate sensor using in-ear infrared detection. 2. Analysis of the temperature signal. 3. Signal processing to detect the heartrate signal from the noise.

Contact Ger de Graaf

Bioelectronics Group

Department of Microelectronics

Last modified: 2022-09-26