Доступ предоставлен для: Guest
Портал Begell Электронная Бибилиотека e-Книги Журналы Справочники и Сборники статей Коллекции
Telecommunications and Radio Engineering
SJR: 0.202 SNIP: 0.2 CiteScore™: 0.23

ISSN Печать: 0040-2508
ISSN Онлайн: 1943-6009

Том 78, 2019 Том 77, 2018 Том 76, 2017 Том 75, 2016 Том 74, 2015 Том 73, 2014 Том 72, 2013 Том 71, 2012 Том 70, 2011 Том 69, 2010 Том 68, 2009 Том 67, 2008 Том 66, 2007 Том 65, 2006 Том 64, 2005 Том 63, 2005 Том 62, 2004 Том 61, 2004 Том 60, 2003 Том 59, 2003 Том 58, 2002 Том 57, 2002 Том 56, 2001 Том 55, 2001 Том 54, 2000 Том 53, 1999 Том 52, 1998 Том 51, 1997

Telecommunications and Radio Engineering

DOI: 10.1615/TelecomRadEng.v51.i4.110
pages 74-78

Multi-Positional Coherent Radar System Antenna Self-Focusing for Transmission as Many Targets Having Equal effective Scattering Areas

N. I. Matyukhin
V. Karazin National University of Kharkiv, 4, Svoboda Sq., Kharkov; N Zhukovski National Aerospace University “KhAI”, 17, Chkalov St., Kharkiv, 61070, Ukraine

Краткое описание

The antenna of a multi-pozitional coherent radar system (MPCRS) is considered as a super-large-aperture very sparse phased array. Antenna modules situated at separate positions are its elements. The modules aperture has sufficiently small dimensions, and a forced focusing of the modules is permissible such that the atmosphere turbulence influence can be neglected. Accordingly, the pattern of an antenna module turns out to be so much wide that several (or group) targets or an extended target with resolvable elements fall within the range of the pattern. Therefore, the overall MPCRS antenna focusing has to be done as to such a group or extended target. If the group target is initially illuminated by a wide beam (e.g. the antenna module beam), the reflected wave received by the overall antenna, the complex conjugate field formed and radiated in the backward direction, then as many narrow beams will be formed for the transmission as the targets were radiated. Essentially, the overall antenna will prove to be focused, but the energy will be splitted up, but d it is not always acceptable. Furthermore, an individual point object (target) is required for the overall antenna focusing for the reception. And so a problem arises, to form one beam for transmission and reception when the initial illumination of the observed group of targets is made by a wide beam.
The known Waters [1] antenna self-focusing method for transmission, when many targets (or an extended target) are illuminated with a wide beam, envisages the formation of one beam for transmission after multiple reception and complex conjugate field reradiation [1]. However, one of the targets of the group being illuminated is presumed to have an effective scattering area (ESA) that differs from other targets ESA. In actual practice, natural and man-made situations can arise in which the group (elements of extended target) under observation have the same ESAs. For instance, stabilized targets such as blunt-nose cone or spherical cone moving along parallel trajectories in radial direction relative to the radar can have practically the same ESAs. A group of targets can be camuflated by inflatable spheres having metalized coating. Special multielement defocusing targets can also be created consisting of metalized inflatable spheres connected by halyards. Extended targets can contain, at certain instants of time, two or more elements having the same ESA etc. Waters method as it was published is unreliable for military-purpose radars. In this connection a practical necessity arises to extend its possibilities to cover the general case where the ESAs of a group of targets or extended-target elements turn out to be the same. Let us consider the general case where one narrow beam for transmission is formed when a group of targets (target element) having rigorously equal ESAs is initially illuminated by a wide beam.

Articles with similar content:

Quasi-Optimum Algorithm for Radioholographic System Antenna Self-Focusing for reception as to Many Targets in the Presence of Additive and Multiplicative Disturbances
Telecommunications and Radio Engineering, Vol.51, 1997, issue 4
N. I. Matyukhin
Formation of Directional Patterns of Planar Antenna Arrays
Telecommunications and Radio Engineering, Vol.65, 2006, issue 16-20
V. A. Katrich, V. A. Lyashchenko
An Approximate Solution to the Problem of Linear Antenna Synthesis by the Partial Pattern Method
Telecommunications and Radio Engineering, Vol.53, 1999, issue 1
O. N. Nosenko
Quasi-Optimum Algorithm for Radioholographic System Antenna Self-Focusing for reception as to Single Target with Its Location Evaluation in the Presence of Additive and Multiplicative Disturbances
Telecommunications and Radio Engineering, Vol.51, 1997, issue 4
N. I. Matyukhin
Backscattering of light from a layer of densely packed random medium
Victor P. Tishkovets