Measuring abdominal fatness using principle of Salisbury screen

The Salisbury-screen characteristics of the human abdomen are demonstrated. The skin-fat-muscle structure in the human abdomen resembles that of the Salisbury screen, which consists of a resistive sheet, a dielectric slab, and a conducting plane. Using this similarity, the authors can estimate the degree of obesity based on the reflectivity of electromagnetic waves. The Salisbury screen acts as a wave absorber when the thickness of the dielectric matches the quarter wavelength. This characteristic is similar to the human abdominal structure. Fat, which has much lower conductivity than skin or muscle, plays the role of the dielectric in the Salisbury screen. Therefore, by measuring the frequency where reflection is minimised, fat thickness can be estimated.