Methods of studying the antennas synthesis problem in practical lessons

Abstract

It is difficult to synthesize the antenna directly in practical lessons in general theory of antennas with students. The approximate method is proposed for solving the synthesis problem based on the minimization of the functional representing the distance in the functional space with a quadratic metric between the normalized desired antenna pattern (AP) and some normalized AP with unknown amplitude and phase distribution (APD) of the field in the aperture. In this case the AP does not necessarily have to relate to the class of realizable ones, and APD of the field, while functional is minimized, can be selected from the set of the functions suitable for implementation.Validity of the method is tested on the example of synthesis of a linear antenna with the APs for which the APD is accurately known. The recommendations for conducting practical lessons are given.

Measurement of the Bridge Surface Deflections Using Near-Field Amplitude of Secondary Radiators System

“…Minimization of this functional by the method of global random search (using a genetic algorithm) leads to estimation of all the displacements of radiators and, consequently, the deviation of the points on the bridge surface. A similar method is used in [20] for antennas synthesis and even earlier in solving the inverse problem of measurement in linear inertial systems or systems with memory [21].…”