A 6.3∶1 bandwidth scanning Tightly Coupled Dipole Array with co-designed compact balun

Abstract

We present a design for a Tightly Coupled Dipole Array (TCDA) with wide angle scanning and a wideband compact balun. Although TCDAs are low profile, capable of wide bandwidth, good scan performance, and low cross polarization, they require a balanced feeding structure whose realization introduces significant practical challenges. Among them is developing a balun that is both compact and wideband. In this paper, we demonstrate a design for a low cost balun that fits within the existing array volume and increases the overall bandwidth of the array. This is accomplished by exploiting the balun's reactance as part of the matching network for the aperture. The final array delivers 6.3 : 1 bandwidth, ±45 • scanning in all planes, and < −10dB cross-polarization. These capabilities are believed to be unique for a low profile array with a self-contained feed.

Feeding of a wideband Superstrate-Enhanced Substrate Loaded Array

“…The advantage of the scheme is that it lowers element impedance, facilitating wideband matching to 50Ω. A key difference between this work and the one presented in [5] is that the use of substrate loading makes this array much more wideband, demanding a more wideband feed design. Fig.…”

“…The cell's two baluns are then fed with a Wilkinson power divider, whose sum port serves as the unit cell's unbalanced interface. This unit cell topology with two radiators, two baluns, and a divider was employed in the designs presented in [5], [6]. The advantage of the scheme is that it lowers element impedance, facilitating wideband matching to 50Ω.…”

Ultra-wideband on-site coding receiver (OSCR) for digital beamforming applications

“…Recently, an UWB tightly coupled dipole array (TCDA) was developed with a compact wideband balun as part of the aperture [1], [2]. The novelty of the proposed array is the elimination of external baluns for impedance matching.…”

Quad frequency stacked patch planar antenna array for radar and navigational applications

“…However, this type of antenna array needs complex feed network, and with the quantity of the elements increasing, the complexity of the feeding network is increasing. Then bring some problems such as there is coupling between elements and feed lines, which will decrease the gain of the array antenna and make the axial ratio terrible . Then, we have to increase the distance between each antenna element to cut down the coupled effects, but it will significantly increase the size of the antenna array again, which does not benefit to miniaturization .…”