Method for detecting fall of child in swimming pool, involves calculating falling situation when energy level of one of rays of spectrum exceeds predetermined threshold with respect to corresponding line in reference spectrum

摘要

The method involves using a piezoelectric element to detect vibrations caused by waves in water and generate an electric signal. A low pass filter (17) is carried out to attenuate frequencies. A spectrum of a filtered signal is calculated in real time. The calculated spectrum is compared with a reference spectrum obtained from history of spectrums stored in memory. A falling situation is calculated when the energy level of one of the rays of the spectrum exceeds a predetermined threshold with respect to a corresponding line in the reference spectrum. An independent claim is also included for a device for detecting fall of a child in a swimming pool.