RADAR  IMAGING SPARSE  ANTENNAS

The use of the nonlinear methods of signal and image restoration, which are able to solve the problem of optimal data interpolation and bandlimited extrapolation simultaneously, makes possible to formulate the problem of the optimal antenna design matched with the features of the restoration algorithm.     The optimal antenna is characterized by the reduced dimensions and smaller general number of antenna array elements (i.e. the reduced number of receivers or general number of positions during aperture synthesis) under condition that the metrology characteristics of imaging system with this antenna are the same ones as with the antenna without considered signal processing. The decrease of the antenna dimension is compensated by the extrapolation abilities of restoration method and the sparseness of antenna (i.e. presence of zero zones in the spatial antenna spectrum) is overcome by interpolation.  The class of optimal sparse arrays is established for real radar imaging applications.      The new non-uniform sampling apertures are studied jointly with the restoration algorithms. antenna 1 antenna 2 Results of direct observation Results of direct observation Restored images Restored images The sparseness of antenna array leads to the increase of the sidelobes that essentially decreases the image quality and causes spatial ambiguity. The developed restoration algorithm makes possible to reduce this ambiguity and to enhance image quality.

If you have any questions or suggestions, please send e-mail:  svolos@cui.unige.ch          Copyright © 1996 - 2001