Diffraction of a Nonharmonic Signal on a Spatially Periodic Structure of a Sawtooth Profile

One of the directions of improving the characteristics of radar systems is the use of ultra-wideband sounding signals. This increases the radar's resolution in all coordinates, stealth of operation, noise immunity, and the possibility of identifying targets on the basis of their radio image. The probability of target detection and stability of target tracking increases. There are a number of difficulties in the process of generation, emission, propagation and reception of ultra-wideband signals. As a model of periodic inhomogeneities of the underlying surface in the propagation of non-harmonic signal in some cases use spatially periodic structures of sawtooth profile. The purpose of the research is to develop a numerical method for solving the problem of diffraction of non-sinusoidal electromagnetic waves on a spatially periodic structure of a sawtooth profile in order to model the propagation of ultrawideband signal over the sea surface. A semi-reversal and frequency method has been used, allowing the use of previously obtained solutions for the harmonic case. A modified method for calculating the scattered field when irradiating a sawtooth profile grating with an ultra-wideband electromagnetic wave is presented. The data of the experiment carried out on the ultrawideband measuring complex show a satisfactory coincidence with the results of numerical calculations and thus confirm the correctness of the mathematical model. The proposed numerical method is an effective means of taking into account the influence of periodic inhomogeneities of the underlying surface on the propagation of a non-harmonic electromagnetic wave. The influence of geometrical and electrophysical characteristics (period, angle of asymmetry, impedance) of the grating on the structure of the scattered field is investigated in detail.