Design of a Coupled Feed Structure With Cavity Walls for Extremely Small Anti-Jamming Arrays

Abstract

This paper proposes a coupled-feed structure accompanied by cavity walls for an extremely small four-element array with an aperture size of less than 0.4λ. The feeding loop of the proposed structure is connected to two output ports of a hybrid chip coupler, and the radiating loop is coupled to the feeding loop through near electromagnetic fields confined within the substrates. This structure allows to increasing the effective dielectric constant of the antenna, which helps to miniaturize the aperture size of the antenna. Another advantage of the proposed structure is that the effective dielectric constant can be adjusted by varying the height of the cavity walls. To verify the operating principles, an equivalent circuit is built, and variations of magnetic field distributions are also observed. Furthermore, performances on interference mitigation are evaluated based on the power inversion algorithm. The results confirm that the proposed structure is suitable to replace current single-antenna systems for an additional capability of effective interference mitigation in such a restricted area. INDEX TERMS Small antenna array, microstrip antenna, coupled feed, anti-jamming, controlled reception pattern antenna.

From Challenges to Success: A road map for early career researchers [Young Professionals]

“…During my academic period, I participated in various projects related to developing antennas for defense systems (Figure 2). I mainly worked on the development of controlled reception pattern array antennas for antijamming purposes in the Global Positioning System (GPS) [1], [2], [3], [4], [5], [6]. I also developed direction-finding systems for unmanned aerial vehicles and radars for cruise missiles.…”

Design and Performance Prediction of a Dual-Band Coupled-Fed Dipole Array Antenna for PCL Systems in the VHF Band

“…The internal dipole is fed directly by the circuit board with the balun, and the external and internal dipoles are electromagnetically coupled to achieve the additional T-DMB band matching characteristics. This coupled-fed mechanism, which has been employed in various broadband microstrip patch antennas [12][13][14], is first applied to the design of dual-band dipole antennas for the VHF frequency band. The coupled-fed mechanism used for the dipole element can achieve the dual-band matching characteristics, which can improve the illuminator of opportunity for PCL systems.…”

“…In this paper, we propose a novel design of an array antenna element that can achieve multi-frequency band operation by applying a coupled-fed technique to a dipole antenna. This coupled-fed technique, often used for broadband matching characteristics of microstrip patch antennas [12][13][14], is first applied to the design of the multi-band dipole antenna for PCL systems. The antenna element comprises an internal dipole and an external coupled-fed dipole.…”

Design of a Compact Indirect Slot-Fed Wideband Patch Array with an Air SIW Cavity for a High Directivity in Missile Seeker Applications

“…However, these antenna designs have a bulky size and an expensive fabrication cost because their feeding networks commonly need metallic waveguide structures and a sophisticated fabrication process. To overcome the demerits, substantial studies on microstrip patch antennas for a low cost and miniaturization have been investigated by employing various techniques that are the use of a substrate with high-permittivity materials [16,17], a cavity structure [18,19], shorting pins [20,21], and a rectangular ring-shaped patch geometry [22]. Although these techniques can reduce the physical antenna size with a high-directive pattern, those microstrip patch antennas have narrow impedance-matching characteristics because of the direct feeding structure.…”