• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.37 no.3
• /
• pp.35-42
• /
• 2000

A cross-shaped microstripline-fed printed slot antenna having wide bandwidth Is presented in this paper. The proposed antenna is analyzed by using the Finite-Difference Time-Domain (FDTD) method. It was found that the bandwidth of the antenna depends highly on the length of the horizontal and vertical feedline as well as the offset position of the feedline. The maximum bandwidth of this antenna is from 1.975 GHz to 4.725 GHz, which is approximately 1.3 octave, for the VSWR $\leq$ 2. Experimental data for the return loss and the radiation pattern of the antenna are also presented. and they are in good agreement with the FDTD results.e FDTD results.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.37 no.12
• /
• pp.32-37
• /
• 2000

We proposed to a new method of the aperture coupled microstrip antenna with T-shaped feeding slot. We analyzed method of enhancing the bandwidth of the antenna using FDTD. And the antenna parameters are optimized to get maximum bandwidth. We also calculated the progress process of waves and the distribution of electric field in the time domain. We also calculated return loss, VSWR, input impedance, radiation pattern in the frequency domain by Fourier transforming the time domain results, respectively. It was found that the bandwidth of this antenna changes length and width of the patch, length and width of the slot, length of T-shaped feedline, position of the offset. Measured % bandwidth was 49.2 % in the center frequency 2.5 GHz. These results were in relatively food accordance with calculated values.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
• /
• 2000.11a
• /
• pp.354-358
• /
• 2000

T-모양의 급전구조를 갖는 마이크로스트립 슬롯 안테나는 정합을 쉽게 이룰 수 있고, 대역 폭이 기존의 슬롯을 가로지르는 급전구조에 비하여 넓었다. 본 논문에서는 역 L-형 마이크로스트립 급전구조를 제안하여 FDTD(Finite Difference Time Domain)법으로 해석하여 안테나를 최적화 설계하였다. 슬롯 폭이 16 mm일 때, 전압 정재파비가 2.0 이하인 조건에서 대역폭은 2.3 GHz를 중심으로 약 48 % 정도의 광대역 특성을 얻었다. 제안된 급전구조는 기존의 슬롯 가로지르는 급전구조의 복사 저항보다 매우 낮았다. 또한 역 L-형 급전구조의 대역폭 특성을 기존의 급전구조의 슬롯릇 안테나들과 비교하였다.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.29 no.8
• /
• pp.576-582
• /
• 2018

In this paper, a planar equi-phase power divider is proposed using fixed phase shifters. As the integrability of a phased array antenna increases for accurate beam steering, a conventional method to excite equi-phase signals to all element antennas, extending the feedline, has spatial limitations. Therefore, the planar equi-phase power divider is designed using a defected ground structure with a planar phase shift function without intentional feedline extension. The defected ground structure has been considered for a low insertion loss and a controllable phase shift, whereas the power divider has been designed and implemented with a port-to-port isolation and a planar configuration.

• Journal of The Institute of Information and Telecommunication Facilities Engineering
• /
• v.2 no.4
• /
• pp.28-41
• /
• 2003

A micros-strip ring patch antenna with ultra wide band characteristics is presented. The proposed antenna is designed by a modified form of the annular ring patch antenna with modified microstrip feedline. The designed antenna gives 5.6GHz bandwidth with regular radiation pattern from 4.4GHz to 12.0GHz for -10dE return loss or VSWR of less than 2.0 in simulation, which is also excellently agreed with the measured data.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.12 no.6
• /
• pp.948-957
• /
• 2001

We proposed a novel feed structure for a broadband circular slot antenna. The proposed antenna has a circular slot, a radiating element, and a novel microstrip feed structure which is composed of a 50 Ω microstrip feedline and a circular-shaped microstrip patch. This antenna is analyzed and optimized by using the finite difference time domain (FDTD) method. The impedance bandwidth of optimized antenna is 1.94 octave that is much broader than the conventional microstrip slot antennas.

• Journal of the Korea Computer Industry Society
• /
• v.10 no.4
• /
• pp.121-126
• /
• 2009

In this paper, the patch antenna for 2.64GHz S-DMB applications has been studied. The patch antenna was designed by HFSS (High Frequency Structural Simulator) program and the optimized antenna was fabricated using photolithography method on the FR-4 substrate. To find optimal conditions of microstrip patch antenna, design parameters with different patch size, length of feedline and metal thickness were analyzed.

• Proceedings of the KIEE Conference
• /
• 1998.07d
• /
• pp.1546-1548
• /
• 1998

Dual mode ring resonators(DMRR) have been fabricated using laser ablated $YBa_2Cu_3O_{7-x}$ superconducting thin films. The transition temperature of YBCO thin films were 85 - 88 K and the film thicknesses were about 5,000 $\AA$. Dual mode ring resonators were patterned by standard photolithography process and wet-etching. Then two-layer metal thin films (Ti/Ag) have been deposited for the ground plane on the back side of substrate by e-beam and thermal evaporation. The input/output feedline angles of each resonator were $60^{\circ}$, $100^{\circ}$, $180^{\circ}$. A network analyzer was used for testing the performance of the resonators in the frequency range of 6-13 GHz at 77 K.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
• /
• 2003.11a
• /
• pp.459-463
• /
• 2003

A circularly polarized microstrip patch antenna (MPA) using electromagnetic (EM) coupled fed method is analyzed in view of the two types of coupling mechanisms viz. cavity and parasitic type, proposed earlier. The patch-ground plane distance is varied in order to achieve the fore-mentioned types of couplings. For each case of patch-ground plane distance, the offset position of feedline is optimized for perfect matching and the boresight axial ratio (AR) is observed. It is seen that CP operation is possible only for cavity-type coupling (smaller patch-ground plane distances). The simulated results for the boresight AR for the two types of coupling mechanisms are presented.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.11 no.5
• /
• pp.773-781
• /
• 2000

We proposed an eccentric annular ring microstrip slot antenna for improving a narrow bandwidth of the conventional annular ring microstip slot antenna. The proposed antenna has an asymmetric slot and a normal microstrip feedline. This antenna is analyzed and optimized by using the finite difference time domain (FDTD) method. The impedance bandwidth of the optimized antenna is more than 1 octave that is much broader than the conventional annular ring microstrip slot antenna for the same size.