The TC-UAJC element presented in this paper uses three main techniques to achieve optimal transmission and minimal reflection over a wide bandwidth below its resonance frequencies. Firstly, tightly coupled elements are used to increase their inter-element capacitance. It should be noted that smaller inter-element spacing produces large bandwidths but can lower the resonance frequency if the resulting capacitance is excessive44. The smaller inter element spacing combined with the subwavelength nature of the MS elements allows field propagation to neighbouring elements and the elimination of impedance variations to give rise to large bandwidths40. In the extreme case when the elements are very small and tightly packed, the current distribution across the MS approaches the Wheeler uniform current sheet concept45. The reduction in resonance frequency comes as a result of the well-known relationship, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\omega =1/\sqrt{LC}$$\end{document}ω=1/LC. Secondly, the horizontal and vertical arms of the TC-UAJC element are tightly coupled to each other for increased intra-element capacitance and thin traces are used for increased inductance, thereby enabling both compactness and an inherently wideband element46. Thirdly, the constituent parts of the element provide closely spaced multiple resonances47 which combine to produce a wide bandwidth.