I'm a student currently working on an university project dealing with the measurement of the heart rate. The heart rate should be measured with a microphone located in a chest strap (similar to polar). Is it possible to use a component that does the measurement instead of developing the filter-circuit? If not, does anyone know where I can find information on the circuit and the measurement? I searched the web and the groups, but did not find anything suitable. In advance: Thank you for your help!!!