Processing device, system and method for processing accelerometer signals for use in monitoring vital signs of a subject

The present invention relates to a processing device for processing accelerometer signals (17, 17a-c) for use in monitoring vital signs of a subject, comprising-a signal input unit (38) for inputting an accelerometer signal (17, 17a-c) of the subject in time, the accelerometer signal (17, 17a-c) being related to at least one physiological event being a cardiovascular or a respiratory event of the subject and measured for at least one spatial direction, an envelope determination unit (19, 40) for determining an envelope signal (21) of the input accelerometer signal (17, 17a-c), a calculation unit (44) for calculating an adjustment factor (43) based on an estimated time interval (45) between a first and a second physiological event of the subject, and a signal adjustment unit (42) for adjusting the determined envelope signal (21) by multiplying the envelope signal (21) with the calculated adjustment factor (43).