Fetal doppler
Ultrasonic fetal heart detectors are low-cost devices use in audio and visual imaging. A variety of health care settings are mean to provide audio and visual information about the fetus. It provides instant assurance of Fetal well-being for both mother and health worker. Fetal heart detectors can easily detect fetal heart sounds. The ability of most units to accurately calculate fetal heart rate during pregnancy, these devices have also made valuable diagnostic tools.
working principle
Fetal heart detectors transmit high-frequency sound waves either continuously or in a continuous-wave (CW) pulse unit, a crystal vibrates like an electric current. This, creating and transmitting acoustic energy, while a second The crystal detects echoes from structures in the body. In pulsed Doppler systems, a single crystal propagates in alternating periodic oscillations. In both the bursting of ultrasonic waves and sensing the resonant energy in the system, the reflected wave is convert into an electrical signal Which can use to create an audible sound or wave.
Ultrasonic heartbeat detectors amplify the audible frequency. By shifting the signal of the returned ultrasonic waves and transmitting it to it. speakers or headphones; Heart rate is determine by either Measuring the timing of peaks in a Doppler signal by or Using automated autocorrelation processes.