Last modified: 2014-02-22
Abstract
The linear holographic processing of wave field while reconstructing a point object image by using a microwave hologram is reduced to the space harmonics summation. To each element of receiving aperture located at a distance p. from the center, there corresponds a space harmonic with a period of T = λR/μ, where λ is the wavelength and R is the distance to the object observed. At the point of the main maximum of the reconstructed image plane the harmonics are summed in phase. At other points of this plane, different space harmonics are summed with different phases.
The proposed non-linear wave field processing includes the same operations upon a signal as in linear processing, but the last operation, i.e., the harmonic summation, is replaced by the multiplication.
As a result of such processing the main lobe of the object image becomes narrower, the sidelobe level decreases and the precision of the angular coordinate measurement becomes an order higher. This may be explained by the fact that the mutual compensation of harmonics appears more efficient when the multiplication is used instead of summation.