1. 32nd Annual International Conference of the IEEE Engineering in Medicine and Biology Society Headset Bluetooth and Cell Phone based Continuous Central Body Temperature Measurement System J. Miguel Sanches 1,2, Bruno Pereira 2 and Teresa Paiva 3,4 1 Institute for Systems and Robotics 2 Instituto Superior Técnico 3 Centro de Electroencefalografia e Neurofisiologia Clínica 4 Faculdade de Medicina da Universidade de Lisboa Lisboa, Portugal

2. 32nd Annual International Conference of the IEEE Engineering in Medicine and Biology Society Abstract The accurate measure of the central temperature is a very important physiologic indicator in several clinical applications, namely, in the characterization and diagnosis of sleep disorders. In this work, a simple system is described to continuously measure the body temperature at the ear. An electronic temperature sensor is coupled to the microphone of a common commercial auricular Bluetooth device that sends the temperature measurements to a mobile phone to which is paired. The measurements are stored at the mobile phone and periodically sent to a medical facility by email or SMS (short messaging service)

3. 32nd Annual International Conference of the IEEE Engineering in Medicine and Biology Society Circadian Cycle of Melatonin Secretion Direct measurement of melatonin secretion is difficult and it is only possible in laboratory or medical facilities. The most used method to indirectly estimate the circadian rhythm of melatonin secretion is the central body temperature

4. 32nd Annual International Conference of the IEEE Engineering in Medicine and Biology Society System

5. 32nd Annual International Conference of the IEEE Engineering in Medicine and Biology Society Electronic Circuit

6. 32nd Annual International Conference of the IEEE Engineering in Medicine and Biology Society Adaptive Sampling Optimize the energy consumption of the auricular and increase its operation time. The sampling rate is adaptively estimated according to the evolution of the temperature curve estimated up to the current time. The sampling rate increases when the derivative of the signal increases and The sampling rate decreases in the slow changes regions

7. 32nd Annual International Conference of the IEEE Engineering in Medicine and Biology Society Adaptive Sampling

8. 32nd Annual International Conference of the IEEE Engineering in Medicine and Biology Society Filtering

9. 32nd Annual International Conference of the IEEE Engineering in Medicine and Biology Society Kalman Filter

10. 32nd Annual International Conference of the IEEE Engineering in Medicine and Biology Society Kalman Filter: missing data Filter Sequence

11. 32nd Annual International Conference of the IEEE Engineering in Medicine and Biology Society Experimental Results

12. 32nd Annual International Conference of the IEEE Engineering in Medicine and Biology Society References