A corporate feed sequentially rotated 2 × 2 circularly polarized fractal antenna array is investigated in this work. Four number of compact circular fractal antenna elements are positioned ...symmetrically across the geometry. The antenna elements in the subarray are incorporated with 1st order Koch fractal cuts and rotated with respect to its neighbor and the phase change thus generated becomes offset with the phase change in the excitation in the corporate feed. A 2nd order Minkowski fractal curve is implemented on the ground plane to optimize the radiation performance of the array. The proposed fractal antenna array (FAA) is powered with a coaxial feed, with its pin connected to the asymmetric line configuration placed on the top surface. The dimensional confinement of the array is limited to 0.904λ0 × 0.876λ0 × 0.012λ0 (fr = 2.27 GHz) and the overall layout of the geometry is built on a FR4 substrate having a dielectric constant of 4.4. The circularly polarized radiation characteristics of the elements are developed as a result of fractal cuts along the vertical and horizontal sides. A maximum gain response of 5.4 dBic is observed in the impedance band ranging from 2 GHz to 2.5 GHz. The measured results of the proposed array are found to be in good agreement. In quantitative comparison with a few existing arrays with respect to its diverse performance the proposed CP FAA is found to be suitable for space-borne applications operating in the S-band.
Summary
This article investigates a compact π‐shaped circularly polarized Minkowski fractal antenna (MFA). The proposed radiator is taking a π‐shape with semicircular cuts along the opposite side of ...the patch with a V‐cut at the bottom. A second‐order Minkowski fractal curve is implemented on the bottom ground plane. The antenna element is powered by a coaxial probe. The asymmetric structure generates two orthogonal modes, which results in circular polarization. A maximum gain response of 7.1 dBic is observed in the impedance band width (IBW) covering 9.7 to 11.2 GHz. The patch is fabricated on substrate RT/Duroid 5880™ (𝜀𝑟=2.2). The antenna has a compact dimension of 0.90λ0 × 0.90λ0 × 0.05λ0 (fr = 10.45 GHz). A good match in the results validates the simulated and measured data in comparison with the existing models from literature with respect to diversity performance, thus making it suitable for radar applications.
A compact π‐shaped circulary polarized high gain fractal antenna is investigated in this work. The proposed radiator is having a π‐shape with Minkowski fractal curve on the ground plane. The compact radiator yields an excellent flat gain response of more than 7 dBic over the impedance bandwidth. A good match in the measured results validates the investigation. Also, the antenna stands out in the performance comparison to the existing models from literature with its diverse radiation performance, thus making it an apt fit for radar applications operating in X‐band.
A compact Koch curve fractal boundary antenna with circularly polarized characteristics is discussed in this article. The radiator is having a square shape with V-slotted truncations along four ...sides. The operational band of the fractal structure operates at 2.18 GHz to 2.3 GHz band. A 2nd order Koch fractal curve is incorporated along the perimeter of the radiating patch. The fractal antenna is excited by a coaxial probe feeding technique, positioned diagonally for the development of circularly polarized radiation. The patch element is designed using HFSS and also fabricated on a substrate (RT/Duroid 5880
TM
) having dielectric constant (ε
r
= 2.2) is used to design the fractal antenna with dimensions 0.39λ
0
× 0.39λ
0
× 0.024λ
0
(f
r
=
2.26 GHz). The structure exhibits a peak gain response of 6.93 dBi along with omnidirectional radiation patterns covering the operational band. The results of simulations and measurements are validated and the presented design is found suitable for space applications.
This research article presents a Koch fractal antenna with wideband characteristics. A threefold scaled down 1st order Koch fractal geometry is etched on the central radiator. The proposed antenna ...operates in the frequency range from 3.6 GHz to 9.5 GHz. The defected ground plane with a rectangular cut is incorporated to further enhance the impedance bandwidth (IBW). The whole geometry is built on a Rogers RT/ Duroid 5880 substrate. The monopole is excited on a line feeding with the best impedance match of 50 \Omega. The areal compactness of the proposed radiator measures 0.677 \lambda_{0} \times 0.611 \lambda_{0} \times 0.034 \lambda_{0}\left(f_{r}=6.55 \text{GHz}\right) and has a −10 dB bandwidth of 90%. The radiator achieves a peak gain measure of 6.8 dBi at 3.7 GHz. Stable radiation characteristics with better X-Pol, covering IBW are observed in this investigation. Hence, the proposed radiator is a fit for C and X-band applications.
The proposed article presents a wideband characterized antenna with fractal geometry. To improve the impedance bandwidth a second-order iterated Koch fractal curve is incorporated on the lower and ...upper edges of the main radiator. The operating frequency of the antenna spans from 1.9GHz to 4.3GHz. The impedance bandwidth of 77\% is achieved due to the implementation of the defected ground structure. The overall geometry configuration is built on a FR4 substrate. The monopole is powered on a line feed attached to the fractal patch with a matched impedance of 50\Omega. The dimensional compactness of the proposed fractal antenna measures 0.641\lambda_{0}\times 0.434\lambda_{0}\times 0.016\lambda_{0}(f_{r}= 3.1 GHz). A maximum realized gain measures to 4dBi at 4.22 GHz with better X-Pol level and stable radiation characteristics covering the entire operational band adds to the merits of this investigation. Thus, the proposed monopole can be considered suitable for application in the S-band.
This paper presents a Koch fractal monopole antenna, which resonates at 2\text{GHz} and 3.44\text{GHz} with {S_{11}} values of - 20.42\text{dB} and - 40.83\text{dB} respectively. The radiator is ...miniaturized by using the fractal technique, and wideband is achieved with the help of the Defected ground structure technique. To achieve impedance matching, a microstrip feedline is considered. FR4 substrate having a permittivity of 4.4 is considered for the design. Overall, the dimensions of the proposed design are restricted to 58{\mathrm{\;mm\;}} \times {{\;}}38{{\;mm\;}} \times {{\;}}1.6{{\;mm}} . This radiator covers the frequency range from 1.76\text{GHz} to 4.29\text{GHz} with an impedance bandwidth of 83.58{{\% }} . This monopole exhibits a VSWR of 1.02. In the operational frequency range, the proposed structure maintains a positive gain with a peak gain of 4.06 at 4.19 GHz. Hence, the proposed antenna can be a suitable candidate for \mathrm{S} and \mathrm{C} band applications.
The proposed work presents a compact hexagonal monopole antenna for wide-band applications. Defected ground structure method is used to enhance impedance bandwidth. The antenna is miniaturized by ...using a hexagonal radiating patch placed on an FR4 substrate material having relative permittivity 4.4. The dimensions of the antenna are limited to 36 mm × 26 mm × 1.6 mm. The antenna covers an operational bandwidth of 66.1% spanning from 3.12 GHz to 6.20 GHz. The proposed monopole shows the S 11 values of -22.6dB and -25.1dB at 3.74 GHz and 5.76 GHz, in the band. A peak gain factor of 2.7 dBi is observed at 5.76 GHz. The presented antenna shows a cross-polar difference of 44 dB with stable radiation characteristics making it suitable for S and Cband applications.
A wideband complementary Koch fractal geometry-based monopole (FMP) is reported in this article. A central radiator and feed line along with a band-enhancing optimized triangular notch is ...incorporated in the design. The monopole is placed on an FR4 substrate material having relative permittivity (\epsilon_{r}=4.3), and loss tangent of (tan \delta=0.02). The size of the FMP is 67 mm \times 37 mm \times 1.6 mm. A partial ground structure is implemented on the compact antenna which attains a bandwidth covering the range from 2 GHz to 4.43 GHz. The proposed FMP covers the 2.4 GHz (ISM) band in the operational frequency range. A maximum gain observed is 3.12 dBi at 3.58 GHz. The fractal MP has stable far-field radiation characteristics thus being suitable for S-band applications.
The reported work is based on a wide band operated linearly polarized element antenna for RFID application. The radiator is built on an FR4 substrate having dimensions 60mm x 40mm x 1.6mm. The ...central radiator consists of a united semicircular patch with a rectangular block. The antenna resonates at 2.1 GHz with an operating range 1.7 GHz to 4 GHz. A maximum of 3.6 dBi realized gain is observed at 1.8 GHz. Stable radiation patterns along with positive gain response has been witnessed throughout the impedance bandwidth. A maximum of 65° beam width is obtained along the bore side direction. Owing to the compactness with improved radiation properties the proposed monopole can be considered useful in RFID applications.
This manuscript investigates a linearly polarized frequency and radiation pattern reconfigurable wideband antenna using two number of PIN diodes for achieving three distinct operation frequency for ...three different combinations of active diodes to switch between different frequency bands, including popular wireless communication frequency bands also used for ISM and IoT band applications. The proposed design exhibits pattern reconfiguration at two different angles for beam scanning. High frequency structure simulator (HFSS) is used to design and optimize the antenna. The compact monopole has dimensional measures of 59mm × 39mm × 1.6mm and has wide bandwidth coverage from 2.04 GHz to 3.26 GHz due to its two major and minor branches like structure thus making it apt for WiMAX and S-band applications.
