An exemplary device for detecting a heartbeat of a patient can be provided which can include a transmitter which can provide ultrasonic waves, a receiver that can receive Doppler-shifted ultrasonic waves, and a hardware analyzer coupled to the receiver and which can evaluate a particular moment of the heartbeat of the patient based on a time-dependent signal obtained from the receiver. The hardware analyzer device can comprise a spectrum analyzer configured to extract time-varying frequency component(s) from the time-dependent signal provided by the receiver, and a processing module which can evaluate the moment of the heartbeat based on a variation of at least one of the frequency components in time. The processing module can determine a window of interest (WOI) in time from the variation of the frequency component(s) in time, and the moment when the time-dependent signal provided by the receiver assumes a maximum within the WOI as the moment of the heartbeat.
