• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.27 no.4
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• pp.403-406
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• 2016

This paper presents the design and implementation of the small size receiver to put a passive microwave sensor for human body detection to practical use. The requirements and specifications of the sensor receiver are drawn using the experimental data of human body detection by the existing sensor operated at 5.1 GHz. The small size sensor receiver to satisfy the drawn specifications is designed and implemented. The effectiveness of the fabricated sensor with small size receiver on human body detection is demonstrated experimentally in laboratory. The results show the sensor can detect human body to within 4 m distance from the antenna. The size and power consumption of the small size receiver are decreased to 60 % and 40 % compared to those of the existing receiver, respectively.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.7
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• pp.3431-3436
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• 2013

Band-notched ultra-wideband (UWB) antennas using frequency selective surfaces (FSSs) are presented. The proposed antennas utilized the band rejection characteristic of typical FSS unit cells. We loaded the FSS unit cells on the same plane of planar UWB antenna. These antennas are designed to reject the interference from the wireless local area network band, 5.15-5.825 GHz in the UWB band, 3.1-10.6 GHz. The measured peak gains of the proposed antennas are more than 2 dBi at both operation edge and center frequencies, and sufficient to apply for commercial purpose. The antennas are small size and planar shape for the purpose of the small mobile application, and enhanced design freedom by using various existing FSS unit cells.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.22 no.2
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• pp.338-346
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• 2018

In this paper, a monopole antenna applicable to WLAN/WiMAX system is designed and fabricated. The proposed antenna is designed to have three lines and one slit based on microstrip feeding to have triple band characteristics. We optimized the lengths and slits of the three lines to obtain the required characteristics for this paper. The proposed antenna has $32.0mm(W2+W3){\times}47.1mm$ (L3+L4+L5+L8) on a dielectric substrate of $42.5mm(W1){\times}52mm(L1){\times}1.0mm$ size. From the fabrication and measurement results, bandwidths of 158 MHz (813 to 971MHz), 630 MHz (2.10 to 2.73GHz) and 1190 MHz (4.83 to 6.02GHz) were obtained based on the impedance bandwidth. The fabricated antenna also obtained the measured gain and radiation pattern in the required triple band.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.14 no.6
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• pp.638-647
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• 2003

Triangular patches have been studied, both theoretically and experimentally. We feund that provided radiation characteristics similar to those of rectangular patches, but with smaller size. In this paper, we designed an equilateral triangular microstrip patch antenna using cavity model analysis. Then, in order to improve narrow bandwidth, we add capacitive gap and air gap. Capacitive gap is located with square shape beside feeding point on the patch, and air gap is inserted between substrate dielectric and ground plane to adjust probe inductance. The analysis of characteristics and effects of each component was performed by commercial simulation tool, Ensemble 5.0. Throughout the simulation and experiment, we found the possibility of bandwidth enhancement in triangular microstrip antenna.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.28 no.7
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• pp.571-575
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• 2017

This paper presents a C-band bi-directional T/R chipset in $0.13{\mu}m$ TSMC CMOS technology for phased array antenna. The T/R chipset, which is a key component of phased array antenna, consists of a 6 bit phase shifter, a 6 bit step attenuator, and three bi-directional gain amplifiers. The phase shifter is controlled up to $354^{\circ}$ with $5.625^{\circ}$ phase step for precise beam steering. The step attenuator is also controlled up to 31.5 dB with 0.5 dB attenuation step for the side lobe level rejection. The LDO(Low Drop Output) regulator for stable 1.2 V DC power and the SPI(Serial Peripheral Interface) for digital control are integrated in the chipset. The chip size is $2.5{\times}1.5mm^2$ including pads.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.16 no.1 s.92
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• pp.66-77
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• 2005

This paper proposed a novel broadband PIFA(Planar Inverted-F Antenna) for IMT-2000/WLAN/DMB terminal. Two branch lines for meander line were utilized in order to improve the characteristics of PIFA which usually has a narrow band. The shorting strip between the ground plane and meander-type radiation elements were used in order to minimize the size of the antenna. The -10 dB return loss bandwidth of a realized antenna was $38.2{\%}$(1.84~2.71 GHz), which contains the broadband bandwidth with triple band. And the simulated and measured values of 1 g and 10 g averaged peak SAR on human head caused by the triple band PIFA mounted on folder-type handsets were analyzed and discussed. As a result, the measured 1 g and 10 g averaged peak SARs of PIFA were similar with the simulated values and were lower than the 1.6 W/kg and 2 W/kg of 1 g and 10 g averaged peak SAR limits.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.29 no.10
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• pp.739-744
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• 2018

In this paper, a double split-ring resonator(DSRR) is proposed to improve the isolation between Vivaldi antenna elements. The DSRR was designed using a unit cell simulation and applied to a $1{\times}2$ Vivaldi antenna array to confirm the improvement in the isolation. The unit cell size of the proposed DSRR is $5mm{\times}5mm{\times}1.52mm$ and six unit cells are used. To verify the performance of the proposed DSRR, $1{\times}2$ Vivaldi antenna arrays with and without the DSRR were fabricated and measured. The results show an isolation improvement of 20 dB in the Vivaldi antennas with the DSRR when compared to the Vivaldi antennas without the DSRR.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.3
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• pp.1129-1133
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• 2015

Background: The tissue microarray (TMA) is widely accepted as a fast and cost-effective research tool for in situ tissue analysis in modern pathology. However, the current automated and manual TMA techniques have some drawbacks restricting their productivity. Our study aimed to introduce an improved manual tissue miniarray (TmA) technique that is simple and readily applicable to a broad range of tissue samples. Materials and Methods: In this study, a conventional TV/radio telescopic antenna was used to punch tissue cores manually from donor paraffin embedded tissue blocks which were pre-incubated at $40^{\circ}C$. The cores were manually transferred, organized and attached to a standard block mould, and filled with liquid paraffin to construct TmA blocks without any use of recipient paraffin blocks. Results: By using a conventional TV/radio antenna, it was possible to construct TmA paraffin blocks with variable formats of array size and number ($2-mm{\times}42$, $2.5-mm{\times}30$, $3-mm{\times}24$, $4-mm{\times}20$ and $5-mm{\times}12$ cores). Up to $2-mm{\times}84$ cores could be mounted and stained on a standard microscopic slide by cutting two sections from two different blocks and mounting them beside each other. The technique was simple and caused minimal damage to the donor blocks. H&E and immunostained slides showed well-defined tissue morphology and array configuration. Conclusions: This technique is easy to reproduce, quick, inexpensive and creates uniform blocks with abundant tissues without specialized equipment. It was found to improve the stability of the cores within the paraffin block and facilitated no losses during cutting and immunostaining.

• Journal of Advanced Navigation Technology
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• v.18 no.4
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• pp.376-380
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• 2014

In the present study, oblique L-shaped monopole slot antenna with broadband characteristic is newly proposed. For bandwidth enhancement as well as size reduction, L-shaped slot with two open-terminations on the ground edge is used. The lower part of L-shaped slot comprises oblique form for bandwidth enhancement in low frequency band, whereas its higher part comprise tapered form for its enhancement in high frequency band. The short-circuit terminated microstrip line which is generally known to be more useful for bandwidth enhancement than open-circuit termination is used. The measured impedance bandwidth($S_{11}{\leq}-10dB$) and gain of the fabricated antenna have been observed to be 4.72 GHz (2.28~7 GHz) and more than 3dBi over the passband respectively.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.26 no.12
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• pp.1044-1049
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• 2015

In this paper, isolation enhanced antenna using isolating resonator was proposed. Two loop type antennas were designed to operate at Wi-Fi band(2.4~2.5 GHz), in symmetry to the center, and are closely located to each other. In order to enhance isolation characteristics at Wi-Fi bands, isolating resonator was designed between the two loop type antennas. The proposed isolating resonator is a slot type antenna that enhances isolation with the control of the size, and by adjusting the value of capacitor($C_D$) the resonant frequency of the isolating resonator can easily be adjusted to enhance isolation characteristic at the target frequency.