A method of monitoring one or more of a heartbeat of a live vertebrate animal and a respiration rate of the live vertebrate animal, the method comprising: measuring a frequency spectrum of radar light reflected off the live vertebrate animal; determining amplitudes of a selected proper subset of the Fourier components of said frequency spectrum; and feeding the amplitudes of the Fourier components of the proper subset and/or parameters derived from said Fourier components of the proper subset into a neural network to make a characterization of the heartbeat and/or respiration rate of the live vertebrate animal.