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Item type:Item, Design and measurement of a probe-fed open-ended rectangular waveguide with four-stacked-coupling-aperture(2019-01-01) ;Lamultree, Suthasinee ;Panthasa, RutPhongcharoenpanich, ChuwongThis paper presents a design and measurement of symmetric bidirectional pattern antenna implemented by using a probe-fed open-ended rectangular waveguide (OERW) vertically attached with four-stacked-coupling-aperture (FSCA). For the OERW without FSCA, it provides asymmetric beam in forwards and backwards directions. With the effect of FSCA, that asymmetry is amended to be symmetry, and propagates the WLAN frequency band of 2.4–2.5 GHz with the return loss better than 10 dB, and maximum gain of 7.04 dBi. A prototype antenna was fabricated and measured. Obviously, the preliminary measured results are very reassuring, and reasonably in good agreement with simulation results. - Some of the metrics are blocked by yourconsent settings
Item type:Item, 5.8 GHz notched UWB bidirectional elliptical ring antenna excited by circular monopole with curved slot(2007-12-01) ;Chawanonphithak, Krittaya ;Phongcharoenpanich, Chuwong ;Kosulvit, SompolKrairiksh, MonaiThis paper presents a UWB bidirectional elliptical ring antenna excited by circular monopole with curved slot for 5.8 GHz band rejection. High Q operation of band notch is obtained in the simulation. The characteristics of the antenna have many attractive features in both technically and economically, such as bidirectional radiation pattern, wide impedance bandwidth, moderate gain, small size, low cost, and easy fabrication. The antenna is desired for application in conventional narrow and long path service area, where some frequency bands pre-occupied by the WLAN standard IEEE 802.11a. - Some of the metrics are blocked by yourconsent settings
Item type:Item, An ultra-wideband bidirectional antenna with modified circular disc monopole excited elliptical ring(2007-08-28) ;Chawanonphithak, Krittaya ;Phongcharoenpanich, Chuwong ;Kosulvit, SompolKrairiksh, MonaiThe antenna design for ultra-wideband (UWB) signal radiation is one of the main challenges of the UWB system, especially when the antenna can satisfy the requirement of low-cost, compactness, linear polarization and bidirectional pattern. This paper proposes a UWB bidirectional antenna with introducing the ψ shape feeder to circular disc monopole (CDM) excited elliptical ring for modern base station in UWB system. The simulation results are presented UWB performance of this antenna by using Computer Simulation Technology (CST®). The return loss of better than 10 dB covers the frequency range from 3 to 25 GHz, directivity at the direction toward θ=0° and 180° from 2.8 dBi at 3 GHz to 4.6 dBi at 11 GHz. The proposed antenna can achieve bidirectional pattern over the bandwidth of 7.5 GHz. The bidirectional radiation pattern is desirable for many applications in long and narrow path service cell. ©2007 IEEE. - Some of the metrics are blocked by yourconsent settings
Item type:Item, NEC simulation of a bidirectional antenna using a probe excited elliptical ring(2005-12-01) ;Chawanonphithak, Krittaya ;Phongcharoenpanich, ChuwongKrairiksh, MonaiThis paper describes the characteristics of a bidirectional antenna using a probe excited elliptical ring. Based on the waveguide principle, a design of elliptical ring cross section that yields the propagation in dominant mode can be chosen and clarified by Numerical Electromagnetic Code (NEC). The quarter wavelength probe can accomplish matching condition. Subsequently, a decision of the ring length that obtains the desired directivity as well as the efficient radiation pattern, standing wave ratio (SWR), polarization, and bandwidth can be found by simulation. To investigate the characteristics of the proposed antenna for applying at the base stations, the wired grid model must be constructed. Using NEC simulation, the antenna characteristics can be carried out. The antenna prototype is fabricated and tested to verify the validity of our design method and the usefulness in Thai Mobile system operated at the center frequency of 1.92 GHz, The proposed antenna radiating bidirectional beam is suitable for narrow and long path service area with simple configuration and cost effective. © 2005 IEEE. - Some of the metrics are blocked by yourconsent settings
Item type:Item, The space diversity analysis of bidirectional antenna using probe excited circular ring(2004-09-27) ;Maruekin, Manoon ;Phongcharoenpanich, ChuwongKosulvit, SompolThis paper presents a space diversity analysis of bidirectional antenna using probe excited circular ring. The theoretical investigation is first carried out. The operating frequency is performed at 1.9065GHz. The electromagnetic fields of the ring with the aperture directs in z-axis is first calculated. Then, the transformations to x direction is achieved. The diversity characteristics such as mean effective gain correlation coefficient, and diversity gain are determined and compared among the arrangement in x,y and z directions. - Some of the metrics are blocked by yourconsent settings
Item type:Item, A simple and cost-effective bidirectional antenna using a probe excited circular ring(2001-01-01) ;Kosulvit, Sompol ;Krairiksh, Monai ;Phongcharoenpanich, ChuwongWakabayashi, ToshioThis paper presents a simple and cost-effective bidirectional antenna using a probe excited circular ring. The structure of the antenna is simple i.e., a linear electric probe surrounded by the circular ring. The principle of the antenna design is easy and straightforward. A choice of the ring radius is first chosen to achieve the condition that only the dominant mode can be propagated. Furthermore, it is found that for a specific ring radius, the radiation patterns of the antenna are varied as the ring width. Then, the optimum ring width that provides the maximum directivity is determined. The criterion of the selection of the ring width for various ring radii is illustrated as the guidelines for the antenna design. The fabricated antennas at the operating frequency of 1.9065 GHz are measured and compared with the theoretical predictions. It is apparent that these results are in reasonable agreement. The bidirectional pattern with the gain of 5.4 dBi over the bandwidth of 17% is obtained. Moreover, the antenna can be easily fabricated with the low production cost. Therefore, this antenna is suitable for installing at the base station in the street cell.
