• Proceedings of the Korea Electromagnetic Engineering Society Conference
• /
• 2000.11a
• /
• pp.408-412
• /
• 2000

In this paper, we present the design and measurement of a collinear dipole array (CDA) operating in the 2.4 GHz ISM band. The array is consisted of six collinear dipoles joined by phasing coils. A cmmercial software is used to design the antenna with an optimum performance. The designed array is fabricated and is measured to confirm the design.

• Journal of Advanced Navigation Technology
• /
• v.27 no.4
• /
• pp.447-452
• /
• 2023

In this paper, gain enhancement of a double dipole quasi-Yagi antenna using a meanderline array structure was studied. A 4×1 meanderline array structure consisting of a meanderline conductor- shaped unit cell is located above the second dipole of the double dipole quasi-Yagi antenna. It was designed to have gain over 7 dBi in the frequency range between 1.70 and 2.70 GHz in order to compare the performance with the case using a conventional strip director. As a result of comparison, the average gain of the double dipole quasi-yagi antenna with the proposed meander line array structure was larger compared to the case with the conventional strip director. A double dipole quasi-Yagi antenna using the proposed meanderline array structure was fabricated on an FR4 substrate and its characteristics were compared with the simulation results. Experiment results show that the frequency band for a VSWR less than 2 was 1.55-2.82 GHz, and the frequency band for gain over 7 dBi was measured to be 1.54-2.83 GHz. The frequency bandwidth with gain over 7 dBi increased, and average gain also slightly increased, compared to the conventional case using a strip director.

• Steel and Composite Structures
• /
• v.17 no.5
• /
• pp.561-572
• /
• 2014

In this paper, we present the scattering characteristics of infinite and finite array using method of moment (MoM) with Floquet harmonics and asymptotic waveform evaluation (AWE) technique. First, infinite cylindrical dipole array is analyzed using the MoM with entire domain basis function and cylindrical Floquet harmonics. To provide the validity of results, we fabricated the cylindrical dipole array and measured the transmission characteristics. The results show good agreements. Second, we analyzed the scattering characteristics of finite array. A large simulation time is needed to obtain the scattering characteristics of finite array over wide frequency range because Floquet harmonics can't be applied. So, we used the MoM with AWE technique using Taylor series and Pade approximation to overcome the shortcomings of conventional MoM. We calculated the radar cross section (RCS) as scattering characteristics using the proposed method in this paper and the conventional MoM for finite planar slot array, finite spherical slot array, and finite cylindrical dipole array, respectively. The compared results agree well and show that the proposed method in this paper is good for electromagnetic analysis of finite FSS.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.23 no.2
• /
• pp.244-250
• /
• 2012

The compact dipole antenna elements and array structure is proposed. The array structure is designed for applicator in regional hyperthermia treatment to enhance the uniformity of the heat distribution which makes the treatment effective and prevents overheating. The compact dipole is designed with branched dipole and matching network to have small size and symmetric shape. The temperature simulation with specific absorption rate(SAR) and bio-heat equation is performed to have heat distribution. The applicator is designed, fabricated, and measured with multi-channel thermometer in 30 and 60 minutes. The simulation and measurement results showed agreement and the simulation in body circumstance has proper temperature result for hyperthermia therapy.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.39 no.5
• /
• pp.251-258
• /
• 2002

In this paper, the dipole-fed planar array antenna applied Yagi-Uda antenna away theory to microstrip antenna is designed and fabricated at X-band. The design procedure of the dipole-fed planar array antenna with the wide bandwidth is presented to be easily practiced to a wireless communication system. The radiation pattern, return loss and bandwidth of the antenna are improved by the finite differential time domain(FDTD) numerical method. The propriety of analysis of planar dipole antenna is proved from the measured data. From the measured results, the antenna maximum gain is 4.9dBi at center frequency of 10GHz and frequency bandwidth is about 40%. Front-to-back ratio is 16dB, and half-power beam-width of E-plane and H-plane are 117$^{\circ}$and 156$^{\circ}$, respectively. When VSWR of antenna is less than 2, the measured results are agreed well with the theoretical values in the frequency range from 7.4GHz to 11.88GHz.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2018.05a
• /
• pp.61-62
• /
• 2018

In this paper, we studied a wideband double-sided dipole antenna operating at 3.5 GHz (WiMAX) band. The each printed dipoles are placed on the both sides of the substrate. It can be easily implemented and is suitable for connection with an active circuit. In order to obtain wideband printed dipole characteristics, thick rectangular shaped dipole is adopted. Feeding Circuit for dipole array and balun were designed for impedance matching with a $50{\Omega}$ microstrip feed line. The antenna is designed by simulation for an operation in the frequency range of 3.4~3.7 GHz Simulation results show that the maximum gain in the 3.5 GHz band is 5.5 dBi and the bandwidth with VSWR less than 2 is about 1 GHz.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.12 no.9
• /
• pp.4095-4100
• /
• 2011

In this paper, a log periodic bow-tie dipole array (LPBDA) antenna for UWB communications is investigated. Bow-tie shaped dipole elements are used instead of general dipole elements for LPDA antennas and the input reflection coefficient and realized gain characteristics of the LPBDA as a function of a flare angle are analyzed. It turns out that as the flare angle of the bow-tie dipole elements is increased, the lowest operating frequency is shifted toward lower frequency and the operating frequency band is increased, but the average gain is decreased. However, the gain variation of the LPBDA is much decreased and the front-back ratio is improved compared to the LPDA. Standard LPDA and LPBDA with a flare angle of 13 degrees are fabricated on an FR4 substrate with a dielectric constant of 4.4 and a thickness of 1.6 mm. Measured gain for the LPDA ranges from 4 to 6.5 dBi at 3.1 to 10.6 GHz band, while that for the LPBDA is in the range of 4.2 to 5 dBi.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.30 no.3
• /
• pp.202-208
• /
• 2019

In this study, an active element pattern (AEP) of a printed dipole was analyzed in 1D and 2D arrays. First, an AEP of the printed dipole was obtained using the simulation in the 2D infinite array. The scan blindness in the 2D array occurred in the E-plane direction at around ${\pm}36^{\circ}$; however, it was barely observed in the 1D array. To analyze the cause of the scan blindness in the 2D array, the dispersion properties of a unit cell was obtained and compared with the scan blindness by frequency change. The difference between the scan blindness of the 1D and 2D arrays was clarified using the comparison of the Q value in the unit cell in the 1D and 2D arrays. Then, the coupling of the electric field in the E-plane direction was observed when nine elements were separated between the two ports in a linearly arranged dipole structure. Finally, the printed dipole array was fabricated, and an AEP was measured for the $11{\times}1$ and $11{\times}3$ sub arrays. The proposed theory was verified using these observations and by comparison with the simulation results.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.20 no.3
• /
• pp.43-51
• /
• 2020

In this paper, the design of 64 array antennas applied to RWP (Radar Wind Profiler) was described. The design point of the antenna is to ensure isolation between each element and to match the vertical / horizontal radiation pattern. To this end, a single element of the array antenna was proposed as a Bend dipole type, and through simulation, When sequentially sending 5 beams including vertical, the east/west/south/north direction was ±20°, and it was confirmed that no Grating Lobe occurred when steering the beam. The 64 array antenna proposed in this paper was designed with performance equal to or higher than that of overseas products, and was confirmed to be applicable to RWP.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.14 no.7
• /
• pp.712-720
• /
• 2003

In this paper, a multi-layered metallic disk array structure(MDAS) excited by cross-dipole elements was proposed for efficiently shaping of flat-topped element patterns(FTEP) with circular polarization. The MDAS excited by cross-dipole elements has advantages to decrease in volume and weight of an overall array antenna and so, it is appropriate for the FTEP applications of a ralativlely low frequency band. In order to verify the effectness of this structure, the MDAS breadboard operated at X-band(7.9 ∼ 8.4 GHz) was fabricated, and its design parameters were experimentally optimized on the basis of the previous design experience. The experimental results were shown that the MDAS could shape good FTEPs of ${\pm}$20$^{\circ}$beam width at least within a 6.1 % frequency band.