Construction of 2D radio images of objects using nonequidistant encoded frequency-time pulse series

摘要

Based on nonequidistant measurements of signals on an equidistant mesh with a length equal to the number of residues modulo a prime p, a multifrequency signal in which the carrier frequency is switched in the next pulse using a code that corresponds to the rearrangement of the primitive roots modulo a prime p is proposed. In comparison with the multifrequency signals with encoded switching of the carrier frequency (Kostas signals), the number of pulses can be decreased by a factor of 2-5. The simulation results are used to demonstrate that such a signal exhibits the button uncertainty function on the range-velocity coordinates. The application of such a signal in the method of inverse aperture synthesis will provide the resolution of bright points on the surface of a rotating object on the range-Doppler frequency coordinates upon coherent processing and range-difference Doppler frequency upon incoherent processing of the reflected signal. The multiplicative processing of the 2D radio images that are constructed using different frequency-time codes is proposed for the suppression of side lobes.