Disclosed is a system for estimating arterial blood pressure. The system includes a heartbeat detection module configured to receive an electrocardiogram signal, and detect one or more QRS complexes of the electrocardiogram signal. The system also includes a photoplethysmographic sensor module configured to trigger a light emitter, thereby generating a plurality of samples of a photoplethysmographic signal. Further, the system includes a blood pressure calculation module configured to receive information about the detected one or more QRS complexes and the plurality of photoplethysmographic signal samples, and calculate at least one blood pressure value based on a pulse arrival time period between the electrocardiogram and the photoplethysmographic signal. Additionally, the photoplethysmographic sensor module is further configured to receive information about the detected one or more QRS complexes, trigger, each time a QRS complex is detected, the generation of the plurality of photoplethysmographic signal samples, and determine a photoplethysmographic signal acquisition period.
