However the oscillation frequency have to be in the SHF band or higher in order to have an
appreciable Doppler frequency shift. In this paper, a FM-CW radar in UHF band is used to
detect this signal by extracting the amplitude modulation of the reflected signal using an
specific digital signal processing. Respiratory rates of 11 and 15 breath per minute have
been measured for two different persons. These values are within the natural range of …