V.V. Razevig, A.S. Bugaev, V.V. Chapursky

In the work on the basis of mathematical modeling comparison of two alternative design of radio vision system for contactless examination problem decision was carried out. In the first design the method for synthesizing of classical microwave holograms (CMH) is used at mechanical scanning by the antenna system (AS) consisting of transmitting and receiving linear filled antenna arrays. In the second design the scanning linear sparse antenna system of MIMO type comprising of minor antenna elements number and realizing a new method of multistatic microwave holograms (MMH) is applied. Research was carried out on an example of reconstruction of radioimages (RI) of objects of the complex form as which phenomenological models of a pistol and a pistol on a body of the person acted, approximated by dense set of the big number of elementary scatterers. It is established, that in case of microwave holograms focusing for single object (pistol) at CMH and MMH methods practically identical high quality RI takes place at single-frequency and at multifrequency radiation in a centimetric wave band 10-16 GHz. Scanning MIMO AS consisting of two linear antenna arrays used at MMH method can be sparse and have approximately about the order smaller of elements number, than at CMH method, and has the identical RI quality. For suppression of insignificant artifacts of diffraction lobe origins at MMH method the application of a dense arrangement of the given number of elements in transmitting or in receiving antenna array is recommended. Another antenna array should remains sparse and has the size caused by the width of a scanning strip. At focusing of microwave holograms of a pistol or other object on a background of a body of the person at single-frequency variants of microwave holography comparable on RI quality are the CMH method with number of receiving and transmitting elements about 130 each and MMH method with MIMO AS in structure of sparse receiving antenna array with 16 elements and filled transmitting antenna array with 8 elements. At single-frequency radiation RI contrast of a pistol on RI background of a person body was insufficient, that is caused by absence of the range resolution and, most likely, excludes application of both kinds of single-frequency microwave hologram in practice. The increase of RI contrast of a pistol at a background of a person body is reached by application of the multifrequency probing signal having at the given width of a 6,0 GHz bandwidth the resolution on range 2,5 cm. In aggregate with the microwave hologram resolution owing to sphericity of wave fronts, the such frequency bandwidth is enough confidently to observe enough thin casing of a pistol, adjoining to a body. Presence of a dense arrangement of transmitting elements of AS in MMH method essentially reduces diffraction lobes artifacts and focused RI has practically the same quality, as well as at focusing CMH at additional enough big gain at number of scanning AS elements.