• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.19 no.9
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• pp.992-999
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• 2008

This paper describes the design of SPST PIN diode switch which has a 2 kW high power handling capability within $50{\mu}s$ switching speed in $20{\sim}100$ MHz VHF-band. Design factors were investigated and it was confirmed by simulation that the characteristics of insertion loss, VSWR, and isolation met design goal. Also, the capability to handle 2 kW high power with maximum fast switching speed less than $20{\mu}s$ was confirmed and insertion loss less than 0.2 dB, VSWR less than 1.17:1, and isolation higher than 40 dB were obtained by experiments.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2000.11a
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• pp.341-344
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• 2000

There are many researches to increase bandwidth of the microstrip patch antenna for wireless LAN. In spite of broad bandwidth, Bow-Tie microstrip patch antenna, broadband microstrip patch antenna, has disadvantages that are low gain and big size. In this paper, stacked Bow-Tie microstrip patch antenna for wireless LAN is designed in 5.725～5.825GHz band. This antenna has characteristics that are broadband bandwidth, high gain and small size compared with microstrip patch antenna. In simulated results, the return loss is -34.2dB at 5.78GHz and bandwidth is 11.345% for VSWR is 2:1 and 7.75% for VSWR is 1.5:1. In measured results, the return loss is -38-45dB at 5.78GHz and bandwidth is 13% for VSWR is 2:1 and 5.6% for VSWR is 1.5:1.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.9A
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• pp.1083-1090
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• 2004

In this paper, a meander-type microstrip patch antenna for application in 5GHz-hand is designed and fabricated To obtain enough bandwidth in VSWR≶2, the foam is inserted between substrate and ground plane, the coaxial probe source 1S used Antenna is simulated varing the length and width of meander line, the position of probe feeding and the thick of airgap. Later antenna is fabricated with optimizated antenna parameter. The measured result of Fabricated antenna obtained IGHz(l7.5%) bandwidth in VSWR≶2, the gain of 7.3-9.5dBi, Unidirectional pattern.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.7
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• pp.1558-1564
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• 2004

This paper shows the design of Active antenna which appled to 5.5GHz RF module for local wireless communication system. The LNA, which was designed Super low noise HJ FET of NE3210S01, is used to obtain a good noise figure characteristics. And the microstrip patch antenna was designed to obtain omnidirectional antenna characteristics. The measured LNA gain is 15 dB, input & output return loss is under -20 dB and VSWR under 1.5. The Single microstrip patch antenna input return loss is under -29 45, VSWR under 1.2.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.4A
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• pp.312-319
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• 2005

In this paper, a meander-type microstrip patch antenna for application in 5GHz-band is designed and fabricated. To obtain enough bandwidth in VSWR<2, the foam is inserted between substrate and ground plane, the coaxial probe source is used. Antenna is simulated varing the length and width of meander line, the position of probe feeding and the thick of airgap. Later anterlna is fabricated with optimizated antenna parameter. The measured result of Fabricated antenna obtained $1GHz(17.5\%)$ bandwidth in VSWR<2$, the gain of $.3\sim9.5$dBi, Unidirectional pattern.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.26 no.11B
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• pp.1620-1627
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• 2001

In this paper, a broadband microstrip antenna for PCS and IMT-2000 service is designed. To obtain the broadband characteristics of an antenna, we utilized the multi-layered structure composed of two foam material layers, parasitic element and aperture coupled feeding network. The broadband characteristic is obtained by changing the size of parasitic element and the height of foam materials. In addition to that, the usage of metal layer at the distance of λ/4 from feed-line, back radiation is reduced. The bandwidth of a single element for VSWR less than 1.3 is about 550MHz. The bandwidth of a designed 1$\times$4 array antenna for VSWR less than 1.3 is about 460MHz. The gain of a designed array antenna is about 11.15∼12.15dBi and the front-to-back ratio is about 30dB.

• Journal of IKEEE
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• v.22 no.2
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• pp.413-419
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• 2018

An UWB(Ultra Wide Band) antenna with band rejection characteristics is designed and implemented. A planar radiation patch with slot, parasitic elements on both sides of strip and ground plane on back side consist the proposed antenna. The slot in the radiation patch and parasitic elements contribute corresponding bands rejection characteristics. The slot contributes for WiMAX(World interoperability for Microwave Access, 3.30~3.70 GHz) band rejection and parasitic elements contribute for X-Band(7.25~8.395 GHz) rejection. Ansoft's HFSS(High Frequency Structure Simulator) was used to design the proposed antenna and performance simulations. Simulation result showed VSWR(Voltage Standing Wave Ratio) less than 2.0 for UWB band except for dual rejection bands of 3.30~3.86 GHz and 7.21~8.39 GHz. And VSWR measurement result for the implemented antenna shows less than 2.0 for 3.10~10.60 GHz band except dual rejection bands of 3.25~3.71 GHz and 7.25~8.46 GHz.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.43 no.2 s.344
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• pp.76-80
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• 2006

In this paper, broadband balanced amplifier has been realized with Three-Arm Branch $90^{\circ}$ Hybrid Coupler at center frequency 2GHz. $90^{\circ}$ Hybrid Branch-Line Coupler has been compared with Three-Arm Branch $90^{\circ}$ Hybrid Coupler. The bandwidth VSWR and gain or proposed amplifier have been 480MHz, 1.06 and 15.47dB, respectively.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.10 no.1
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• pp.142-149
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• 1999

In this paper, Aperture-coupled microstrip array antenna was designed and manufactured for satellite communication at Ka-Band. We analyzed a microstrip radiation element and designed power divider using $\lambda$g/4 transformer and T-junction power divider. A manufactured Aperture-coupled $2\times2$ microstrip array antenna has a resonant frequency of 20 GHz. The experimental results are as followings : resonant frequency of 19.62 GHz, VSWR 1.0692, return loss -29.61 dB, Bandwidth 1.76 GHz and -3 dB beamwidth $42^{\circ}$.

• ETRI Journal
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• v.32 no.4
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• pp.618-621
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• 2010

A low cross-polarization broadband stacked patch antenna is proposed. By means of the stacked patch configuration and probe-fed strip feed technique, the VSWR 1.2:1 bandwidth of the patch antenna is enhanced to 22% from 804 MHz to 1,002 MHz, which outperforms the other available patch antennas (<10%). Furthermore, the antenna has a cross-polarization level of less than -20 dB and a gain level of about 9 dBi across the operating bandwidth. Simulation results are compared with the measurements, and a good agreement is observed.