Current Issue : January-March Volume : 2026 Issue Number : 1 Articles : 5 Articles
This paper presents the design and development of a reconfigurable circular array antenna capable of producing ten distinct radiation beams, intended for wireless systems in the sub-6 GHz frequency band. The antenna structure is based on four pentagon-shaped radiating elements arranged symmetrically around a central circular patch, which is excited through a coaxial feed. These radiating elements are linked by four circular segments, ensuring mutual coupling for effective operation. A systematic dimensional analysis has been conducted to optimize electromagnetic performance, resulting in a compact and efficient architecture. The beam reconfiguration is achieved through the control of four PIN diodes, which allow the main radiation beam to switch among ten different orientations in the azimuth plane. Specifically, the antenna supports eight directional states, oriented at 45◦ intervals, and two additional bidirectional states covering opposite directions. A prototype has been fabricated and experimentally validated, confirming the steering capability of ±40◦ in both the XZ and YZ planes. Performance evaluation shows a maximum gain of 9.29 dBi and efficiency levels ranging from 91% to 97%. Bandwidth varies across states, with 9.72% for S1–S7, 7.45% for S2–S8, and 4.61% for S9–S10. Overall, the proposed design demonstrates optimized bandwidth, gain, efficiency, and complete azimuthal coverage....
A novel polarization-reconfigurable 1 × 8 array beam-scanning antenna based on a switchable vertically crossed balanced feed (VCBF) structure is presented. The designed VCBF structure can provide a stable 180◦ phase difference by utilizing spatial symmetry, enabling the synthesis of two linear polarizations (LP). The parasitic patch layer loaded directly above the VCBF can effectively enhance the operating frequency bandwidth of the antenna. In the array design, by controlling the amplitude and phase input at each port, scanning angles of ±45◦, ±40◦, and ±30◦ can be achieved under two LP at 3.0, 3.5, and 4.0 GHz. The simulation and measurement results indicate that the designed antenna has a wideband characteristic with a relative bandwidth of 28.6% and stable polarization reconfigurability. Benefiting from the advantages of polarization reconfigurability and beam-scanning capabilities, the antenna is highly suitable for applications in wireless communication systems that require polarization anti-interference....
In this paper, a method to reduce mutual coupling between an E-plane and H-plane coupled microstrip patch antenna is presented. Two dual differentially fed square patches are designed in a 1 × 2 antenna array configuration. To minimize mutual coupling and its effects, coupled split-ring resonators (SRRs) are designed, characterized and positioned between the patches. Circular SRRs are designed and coupled to produce a band-stop response to suppress surface waves propagating within the dielectric substrate while enhancing isolation. Mutual coupling interactions and the suppression mechanism are discussed in relation to the patches and SRRs. The patch radiators are dual differentially fed to achieve polarization diversity. E- and H-planes decoupling is achieved between the two patches throughout their bandwidth while maintaining good antenna performance. A prototype of the antenna array and the SRR is fabricated and measured to validate the decoupling approach. With a separation distance of 0.49λ between the patches, the measured S-parameters show an impedance bandwidth of |S11|≤ −10 dB, covering 9.27–9.46 GHz, and −38 dB and −35 dB mutual coupling for E- and H-planes, respectively, are observed throughout the antenna operating bandwidth....
This paper presents a low-cost 1-bit phased array operating at 17 GHz (Ku band) with an enhanced scanning gain at the largest deflection angle to extend the beam coverage for ground target detection. The phased array is designed using 16 (2 × 8) radiation-phase reconfigurable dipoles and a fixed-phase feeding network, achieving 1-bit beam steering via a direct current (DC) bias voltage of ±5 V. Measurement results demonstrate a peak gain of 9.2 dBi at a deflection angle of ±37◦, with a 3 dB beamwidth of 94◦ across the scanning plane. Compared with conventional phased array radars with equivalent peak gains, the proposed design achieves a 16% increase in the detection range at the largest deflection angle....
This paper proposes wideband circularly polarized (CP) 1-D connected array antennas with slant slot feeders and gradient artificial dielectric layers (ADLs). The slant slot feeder introduces an identical electric field (E-field) along the x- and y-directions. Three slabs consisting of multiple ADLs are stacked above the slot feeder. Due to the different boundary conditions of a 1-D connected array in the zx- and zy-planes, the guided wave in the slabs exhibits different multipath lengths along the x- and y-directions, leading to a 90◦ phase difference between the Ex and Ey components. Moreover, the cascaded slabs are designed with gradient effective permittivities for a gradual impedance transition from the guided mode to the radiating mode, allowing for wideband matching and CP performance. To validate the proposed design approach, an 8 × 1 array was fabricated and measured. The antenna shows a 1.96:1 (10.1–20 GHz) impedance bandwidth (VSWR < 2) and a 1.46:1 (12–17.5 GHz) 3 dB axial ratio bandwidth in measurement. The array exhibits an average right-hand CP boresight gain of 12.39 dBic. Moreover, we produced a frequencyinvariant beam pattern with an average half-power beamwidth (HPBW) of 24.77◦ and a standard deviation below 3.63◦ over 12–18 GHz for the target pattern, with a HPBW of 26◦, demonstrating wideband electronic warfare performance using the proposed array....
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