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Item type:Item, Corner-truncated patch antenna with parasitic elements and circular feed slot for S-band CubeSat applications(2025-12-01) ;Hemachai, Thanaphon ;Dentri, Sitthichai ;Janpangngern, Pisit ;Phakphisut, WatidTorrungrueng, DanaiThis study presents a corner-truncated patch antenna with symmetrically loaded parasitic elements and a circular feed slot designed for CubeSat S-band communication applications. The antenna design evolves through successive stages, integrating corner truncations, a slit-ring structure, and segment-circular parasitic patches to enhance impedance matching and polarization performance. In its final configuration, a dual-stacked arrangement with inter-substrate spacing and a vertical capacitive feed further improves current distribution symmetry and broadens the operational bandwidth. Parametric analysis validates the effectiveness of each antenna design refinement, demonstrating improvements in impedance bandwidth, axial ratio bandwidth, and gain performance. The fabricated prototype achieves a wide impedance bandwidth from 1.65 GHz to 2.70 GHz, fully encompassing the CubeSat uplink (2.025–2.110 GHz) and downlink (2.200–2.290 GHz) frequency ranges. It maintains an axial ratio below 3 dB across 1.97 GHz to 2.32 GHz, ensuring efficient circular polarization. Additionally, a stable gain of approximately 7.50 dBic at 2.025 GHz supports reliable communication with ground stations. The combination of compact structure, low profile, and wideband circular polarization makes the proposed antenna a promising candidate for CubeSat communication systems. The novelty of this research lies in the integration of a corner-truncated patch, symmetrically loaded segment-circular parasitic elements, and a circular slit-ring capacitive feed within a dual-stacked substrate configuration to achieve wideband circular polarization and stable unidirectional radiation. - Some of the metrics are blocked by yourconsent settings
Item type:Item, Investigations of a Circularly Polarized Slotted Corner-Truncated Microstrip Patch Antenna with Split-Ring AMC Reflector(2025-01-01) ;Ainthachot, Chalanthon ;Janpangngern, Pisit ;Dentri, SitthichaiPhongcharoenpanich, ChuwongThis paper presents the design and development of a circularly polarized slotted corner-truncated microstrip patch antenna integrated with a split-ring artificial magnetic conductor (AMC) metasurface for WLAN applications at 2.45 GHz. The antenna design incorporates structural adaptations, such as slotted apertures and corner truncations, to enhance impedance matching and achieve circular polarization. To further improve performance, a split-ring AMC metasurface was employed, resulting in enhanced polarization purity and bandwidth. The proposed design achieves an impedance bandwidth (|S<inf>11</inf>| below -10 dB) from 2.33 GHz to 2.75 GHz and an axial ratio (AR) below 3 dB over the frequency range of 2.40 GHz to 2.55 GHz, and a peak gain of approximately 4.40 dBic at 2.45 GHz. Simulated results are validated by measured results of the fabricated prototype, demonstrating close agreement and confirming the robustness of the design methodology. This work highlights an innovative approach to compact and high-performance antenna design, ensuring its suitability for modern WLAN communication systems. - Some of the metrics are blocked by yourconsent settings
Item type:Item, Conceivable Design of a Wideband Unidirectional Antenna using Truncated Microstrip Patches for S-Band Applications(2025-01-01) ;Hemachai, Thanaphon ;Janpangngern, Pisit ;Dentri, SitthichaiPhongcharoenpanich, ChuwongThis paper presents the conceivable design of a wideband unidirectional antenna suitable for CubeSat applications operating in the S-band frequency ranges of 2.025-2.110 GHz (uplink band) and 2.200-2.290 GHz (downlink band). The antenna employs a truncated microstrip patch design combined with additional parasitic patches to achieve circular polarization. It is printed on an RT/duroid<sup>®</sup> 5880 substrate with a thickness of 0.6 mm and a relative permittivity of 2.2. The design consists of a central truncated radiating patch and four segment-circular parasitic patches, positioned near the edges of the substrate to enhance bandwidth and axial ratio performance, which is crucial for achieving circular polarization. The antenna is excited using a coaxial probe feed to ensure efficient energy transfer and proper impedance matching. Simulation results demonstrate that the antenna achieves a wide impedance bandwidth covering 1.80 GHz to 2.40 GHz with a reflection coefficient (|S11|) below -10 dB. The axial ratio remains below 3 dB across the frequency range of 2.025 GHz to 2.290 GHz, confirming circular polarization, with a minimum axial ratio of 1.34 dB at 2.25 GHz. Additionally, the antenna exhibits a stable gain of approximately 7.28 dBic at 2.15 GHz, making it suitable for CubeSat communication systems requiring reliable and efficient signal transmission. To further strengthen the contribution of this research, a performance comparison with existing CubeSat antennas is provided, along with a discussion of potential environmental impacts in space, such as temperature variations and radiation effects. Future work will focus on prototyping, experimental validation, and optimizing the antenna design for different mission scenarios, including scaling for other frequency bands and multi-antenna configurations. - Some of the metrics are blocked by yourconsent settings
Item type:Item, Broadband CP corner-truncated microstrip antenna with irregularly hexagonal AMC for 2.45 GHz applications(2024-06-01) ;Wichaidit, Purichaya ;Dentri, Sitthichai ;Janpangngern, Pisit ;Lertwiriyaprapa, TitipongKrairiksh, MonaiThis research proposes a compact broadband circularly polarized (CP) corner-truncated microstrip antenna with irregularly hexagonal artificial magnetic conductor (AMC) for 2.45 GHz WLAN applications. The corners of the radiating patch are diagonally truncated to realize circular polarization and improve axial ratio. A 5[Formula presented]5 irregularly hexagonal AMC array is employed to enhance the axial ratio bandwidth (ARBW) and antenna gain. In addition, a tri-section meandering feedline is used to realize impedance matching and improve the impedance bandwidth (IBW). The AMC array is used to manipulate electromagnetic waves by suppressing surface currents and back lobe, resulting in reduced back radiation and enhanced front-to-back ratio. The simulated IBW and ARBW are 50.9% (1.86 – 3.13 GHz) and 19.3% (2.24 – 2.72 GHz) respectively, with a maximum gain of 8.9 dBic at 2.45 GHz. The measured IBW and ARBW are 42.42% (1.95 – 3.0 GHz) and 29.4% (2.03 – 2.73 GHz), with a maximum gain of 8.6 dBic. The simulated half power beamwidth (HPBW) of the proposed antenna scheme in the xz plane at 2.24 GHz, 2.45 GHz, and 2.72 GHz are 67°, 62°, and 51°, respectively. The corresponding HPBW in the yz plane are 60°, 55°, and 62°. The simulated AR beamwidth in the xz plane at 2.24 GHz, 2.45 GHz, and 2.72 GHz are 177°, 164°, and 88°, respectively. The corresponding AR beamwidth in the yz plane are 148°, 106°, and 124°. The simulated cross polarized (XP) levels at 2.45 GHz are below -19.35 dB for both planes. The measured HPBW in the xz plane at 2.24 GHz, 2.45 GHz, and 2.72 GHz are 69°, 64°, and 50°, respectively. The corresponding HPBW in the yz plane are 65°, 54°, and 37°. The measured AR beamwidth in the xz plane at 2.24 GHz, 2.45 GHz, and 2.72 GHz are 161°, 200°, and 104°, respectively. The corresponding AR beamwidth in the yz plane are 162°, 85°, and 90°. The measured XP levels at 2.45 GHz are below -15.62 dB for both planes. The radiation pattern is unidirectional. Essentially, the proposed broadband CP antenna scheme is suitable for the WLAN frequency band and other 2.45 GHz wireless communication technologies. The novelty of this research lies in the use of the tri-section meandering feedline and the irregularly hexagonal AMC array to enhance IBW and ARBW. - Some of the metrics are blocked by yourconsent settings
Item type:Item, Dual-Band Circularly Polarized Omni-Directional Biconical Antenna With Double-Circular Parallelepiped Elements for WLAN Applications(2022-01-01) ;Janpangngern, Pisit ;Torrungrueng, Danai ;Krairiksh, MonaiPhongcharoenpanich, ChuwongThis research proposes a novel dual-band (2.45/5.80 GHz) omnidirectional circularly polarized (CP) biconical antenna with double-circular parasitic parallelepiped elements for wireless local area network (WLAN) applications. The proposed dual-band CP antenna scheme consisted of a biconical radiating structure surrounded by inner- and outer-circular parallelepiped elements that convert linearly polarized electric fields into CP fields. Simulations were performed to optimize the antenna parameters, and an antenna prototype was fabricated and experiments were conducted. The measured impedance bandwidths (IBWs) were 44.4% (1.84 - 2.89 GHz) and 4.56% (5.73 - 5.99 GHz) for the lower- (2.4 GHz) and upper-frequency (5.80 GHz) bands, respectively. The corresponding 3-dB axial ratio bandwidths (ARBWs) were 11.22% (2.27 - 2.54 GHz) and 10.49% (5.6 - 6.2 GHz). The radiation patterns of the dual-band antenna scheme were omnidirectional left-hand circular polarization, with the measured antenna gains of 3.2 dBic and 8.5 dBic at 2.45 and 5.80 GHz, respectively. The simulated and measured results were reasonably agreeable. Despite the narrow IBW and ARBW for the upper-frequency band, the bandwidths adequately covered the target upper frequency band, rendering the proposed CP omnidirectional biconical antenna scheme operationally suitable for WLAN applications. Furthermore, the novelty of this research lies in the use of a biconical radiating structure augmented with double-circular parasitic parallelepiped elements to realize circular polarization for dual-band WLAN applications. - Some of the metrics are blocked by yourconsent settings
Item type:Item, Inverted l-shaped cp patch antenna with corner-truncated partial ground plane diagonally adjoined with square branch for l-band applications(2021-02-02) ;Boontamchauy, Phanuphong ;Lertwiriyaprapa, TitipongPhongcharoenpanich, ChuwongThis research proposes an inverted L-shaped patch antenna with a corner-truncated partial ground plane diagonally adjoined to a square branch for L-band applications. The adjoining square branch was used to perturb linear polarization for circular polarization, and the corner-truncated partial ground plane was utilized to enhance the axial ratio bandwidth (ARBW). Simulations were performed, an antenna prototype was fabricated, and experiments were carried out. The simulation and measured results were in good agreement. The proposed antenna could achieve an ARBW of 77.87% (1.09–2.48 GHz). The novelty of this research lies in the concurrent use of a square branch and a corner-truncated partial ground plane to realize wide ARBW in an L-band, rendering the technology suitable for satellite communication and navigation applications. - Some of the metrics are blocked by yourconsent settings
Item type:Item, Analysis and design of circularly polarized capacitively-fed planar suspended antenna for universal UHF RFID applications(2020-01-01) ;Boonying, KomkrisPhongcharoenpanich, ChuwongThis research paper deals with the design of a circularly polarized reader antenna with a tennis ball-shaped radiating plate that operates at a frequency range of 860-960 MHz with the center frequency of 910 MHz. In the fabrication of the tennis ball-shaped radiating plate, a small annular-ring slot was first created on a circular radiating plate, followed by two diagonally opposite large arc-shaped annular-ring slots on either edge of the circular radiating plate and then the truncation of the corners of the remaining main element of the plate. A prototype antenna with the final tennis ball-shaped plate was subsequently assembled prior to excitation by the capacitively coupled feed technique to enhance |S11| bandwidth. The prototype antenna could achieve an average gain of 6.18 dBic, |S11| covering the frequency range of 837.6-966.2 MHz, and the circular polarization of 850.6-963.5 MHz, making it suitable for universal UHF RFID applications. In addition, simulations were carried out using CST Microwave Studio for comparison with the experimental results. - Some of the metrics are blocked by yourconsent settings
Item type:Item, Broadband circularly polarized microstrip patch antenna using circular artificial ground structure and meandering probe(2020-01-01) ;Pookkapund, Khanet ;Sakonkanapong, Arnon ;Kuse, Ryuji ;Phongcharoenpanich, ChuwongFukusako, TakeshiTo enhance axial ratio (AR) bandwidth, this research proposes a circularly polarized (CP) single-fed microstrip patch antenna using a circular artificial ground structure (AGS) and meandering probe. To achieve broader AR bandwidth, the circular AGS is populated with rectangular unit cells and partially cut unit cells along the circular contour, while the meandering probe is used to improve the impedance bandwidth. Simulations are performed and results compared with that of conventional rectangular-AGS antenna. The simulation results show that the circular-AGS antenna, given 62 mm circular ground plane, achieves broader impedance (5.12 - 9.00 GHz and 54%), AR (5.21 - 8.27 GHz and 45%) and gain bandwidths (3.85 - 7.00 GHz and 58.06%), in comparison with the rectangular-AGS antenna (4.50 - 7.45 GHz and 49%; 4.52 - 7.42 GHz and 21%; and 4.00 - 6.80 GHz and 51.58% for impedance, AR and gain bandwidths). The circular-AGS antenna is capable of converting linear polarization in the off-axial ratio band into circular polarization. To verify, a circular-AGS antenna prototype is fabricated and experiments undertaken. The experimental impedance, AR and gain bandwidths of the circular-AGS antenna are 47.82% (5.17 - 8.42 GHz), 43.81% (5.24 - 8.17 GHz) and 60.74% (3.75 - 7.00 GHz). The proposed circular-AGS antenna can achieve broader AR bandwidth and is thus ideal for broadband CP applications. The novelty of this research lies in the use of circular AGS to effectively enhance AR bandwidth, as opposed to rectangular AGS which is conventionally used in CP polarizers. - Some of the metrics are blocked by yourconsent settings
Item type:Item, Design of circularly polarized and electrically small antenna with omnidirectional radiation pattern(2014-12-01) ;Lertsakwimarn, Kittima ;Phongcharoenpanich, ChuwongFukusako, TakeshiThis paper presents an electrically small and circularly polarized antenna with an omnidirectional radiation pattern. The antenna consists of a horizontal loop element enclosed by two U-shaped elements and a vertical element from the feeding point. The radiation pattern of the circular polarization is omnidirectional and has a maximum gain of -2 dBic in parallel to the ground plane at the 900 MHz band. The antenna dimensions are 48 × 20 × 13.8mm (0.14 λ × 0.06 λ × 0.04 λ) with ka = 0.476 (i.e. < 0.5), where k is the wavenumber at the resonant frequency and a is the radius of a sphere surrounding the antenna. The dimension corresponds to the definition of an electrically small antenna. The omnidirectional circularly polarized pattern of a prototype antenna shows good agreement with that of the simulation. In addition, this paper introduces a mechanism that generates omnidirectional circular polarization from electrically small antennas. - Some of the metrics are blocked by yourconsent settings
Item type:Item, Circularly polarized UHF-RFID antenna using defected rectangular plate on the ground plane(2012-11-26) ;Phongcharoenpanich, ChuwongDentri, SitthichaiThis paper presents a UHF-RFID reader antenna radiating circular polarization with unidirectional pattern. The antenna structure consists of two plates. The upper plate acted as radiating element contains notched rectangular plate, rectangular aperture and slot line. The lower plate is the ground plane. The parametric study is carried out to achieve the frequency response of 920-925 MHz according to Thailand standard of UHF-RFID system. The prototype antenna was fabricated and measured. The simulated half-power beamwidth (HPBW) in E- and H-planes are 65 and 68 degree, respectively. The measured HPBW in both planes is identical to 55 degree. The simulated and measured bandwidths are 7.26% and 10.7%, respectively. The simulated and measured axial ratios at 922.5 MHz are 0.64 dB and 0.09 dB, respectively. © 2012 IEEE.
