Stealth Design Of Wideband Antenna And Array On Low RCS Carrier

Stealth performance of target has become an important development index of weapons and equipment in the modern electronic information war. The stealth design of broadband antenna on the low RCS platform is a hot research topic in recent years. This paper mainly studies the Tapered Slot Antennas’(TSAs’) radiation and scattering characteristics, and takes some stealth designs about Vivaldi antenna and its distortion’s arrays. The specific research contents include:Firstly, we analysis the basic theory of antenna scattering, and consider the open circuit and short circuit load with different scattering field values, then derived the antenna scattering field with an arbitrary load through the antenna scattering theory formula, meanwhile separate the structure and mode scattering field. And summarize some general methods of band broadening and RCS reduction of microstip antennas.Secondly, we design a typical Vivaldi antenna, and present the S11, gain pattern, Radar Cross Section(RCS). Then we systematically analysis and compare the Vivaldis’ RCS characteristics with different gradient line and feed mode, and choose antipodal Vivaldi antenna which has lower RCS as reference, get two improved stealth antennas by replacing the index gradient line with Bessel curve, and effectively reduce the RCS in the operating frequency band(4.3GHz ~ 12GHz), expand the impedance bandwidth at the low frequency end at least 0.5GHz. Slotted type continuation of substrate is useful to Vivaldi antenna’s RCS.And then, based on different array’s unit load effects the phase of antenna RCS by which can make the total scattering field generate mutual inhibition, we can control the array’s RCS by adjusting unit’s loading or its feeding phase. Then use the Vivaldi antenna balun changes produce different wave path, arrange the array on the ladder, make the reflected wave and incident wave coherent offset, decrease array RCS without affecting its radiation characteristics.Finally, we design a broadband wave absorbing structure WRAM and place H plane Vivaldi array in different platform. The simulation results show that WRAM and sloping smooth surface can effectively reduce the array RCS to achieve stealth design.