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Half‐hexagonal microstrip antenna (H‐HMSA) is a compact version of HMSA, as it resonates at the same fundamental mode frequency. In this article, a compact configuration of a single layer, broadband gap‐coupled H‐HMSA has been proposed. Gap‐coupled H‐HMSA is fed indirectly by a λ/2 microstrip‐line resonator. Broad bandwidth (BW) is achieved with an effective use of resonance introduced by λ/2 resonator and gap‐coupled half‐hexagonal radiating patches. A peak gain of 7.07 dBi and measured BW (S11 ≤ −10 dB) of 11.5% at the center frequency of 5.2 GHz have been achieved, which occupies a small volume of 0.023 λ03 including the ground plane. The radiation patterns remain in the broadside direction throughout the return loss BW. Simulated results of the proposed antenna configuration are experimentally validated with good agreement.

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A circular microstrip antenna (CMSA) cannot be fed directly with 50 Ω microstrip (MS) line, without an inset or an impedance transformer, as all around the periphery the impedance is equally high. The feeding technique such as inset fed or quarter wave transformer makes the antenna geometry asymmetrical. In this paper, a technique using single shorting post and a pair of shorting posts is proposed to match the peripheral impedance of the CMSA with that of the 50 Ω-MS-line feed for operation around 2.45 GHz. The shorting posts perturb the current distribution on the patch, altering the input impedance at the periphery. By selecting proper shorting posts positions a wide range of impedance has been adjusted without altering the patch geometry. Due to symmetric arrangement of the double shorting posts, the proposed antenna configuration has a very low cross-polarization ratio of better than −65 dB at the broadside direction for 2.45 GHz. The simulated results of the directly fed 50 Ω-MS-line CMSAs are experimentally validated with good agreement.