• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.25 no.9B
• /
• pp.1635-1640
• /
• 2000

In this paper, a 18 GHz oscillator is designed with the push-push method an fabricated by semi-MMIC process, in which the second harmonic is the main output signal with the suppressed fundamental mode. In semi-MMIC process, passive components with microstrip transmission line are implemented using MMIC process on semi-insulating GaAs substrate. Then, chip types of P-HEMT, resistors, and capacitors are connected through Au wire-bonding. Also, the ground plane is inserted around the circuit and connected each other with the back-side of substrate through Au wire-bonding instead of via-hole. The semi-MMIC push-push oscillator shows the output powder of -10.5 dBm, the fundamental frequency suppression of -17.3 dBc/Hz, and the phase noise of -97.9 dBc/Hz at the offset frequency of 100 kHz.

• Journal of the Korean Society of Costume
• /
• v.22
• /
• pp.205-224
• /
• 1994

It was aimed to study the costume of Koryo dynasty based upon the thirty pictures of Bud-dha to hang on the wall among the existing Buddist paintings. The costume to study were made about 64 years during the King Chung-yol(1286) to the King Chung-jong(1350) which style was mostly related in Won Dynasty. 가) Men's wear ; 1. Hair style and hair dress ; Man tied up a top knot and they put on the hat such as a Kuan Kun and Mo. The young boys binds his hair up one, two, and three knot-s, and tied up with a hair ribbon, A kinds of Kuan-mo were Mine-lu-kuan Yuan-yu-kuan, Nong-kuan, Hae-chi-kuan Pok-du Yun-wha-kuan Yip-mo- and Tu-ku(Helmeto) 2. clothes ; 1) Colour of Koryo King's Mien-ku Kuan costume was not agree with blue and reddish black colour which was used in Yo, Song, Kum and Won Dynasty, however black and greenhish blue colour was agreed with. 2) The king wore T'ung-t'ien-kuan(Yuan-yu-kuan) and the government officials wore Chin-hien-kuan Hae-chi-kuan and Nong-kuan as a court dress. In general the king and the Crown Prince wore a hats which was used in T'ung-t'ien system however sometimes they wore small hats which was cited in literature. 3) Gate guard and upper garment wore colourful costume figured gold colour pattern which was distin-gtive costume system of Koryo. 4) A monk wore big sleeve long skirt big sleeve long jacket long skirt and shoulder scar-f full shoulder scarf or right hand shoulder opened scarf. 5) The Soldiers wore helmet shoulder or scarf pee-back hung-kap, pok-kap, yang-dan-g-kap we-yu-kap kun-kap, and boots and they carried arms. 6) The young boys wore scarf, loin cloth, long skirt, belt neckless, wan-silk, boots and foots wear and wristless. 나) Women's wear ; 1. Hair style and hairs and tied up with a hair ribbon and wore precious ston decorated hair dress wheel shape hair dress pan shaped head dress handkerchif covered hair dress decorated precious stone hair pin silk chippon made of head dress muf-fler shaped hairdress. Boots mocasin hae lee, suk and sandle wored as a shoes depends on the classes. They wore neckless, earing wres-tless and wan-pu-sik. 2. Closthe 1) High rank lade's wore un-kyun attached jacket and jacket sleeves decorated pleats and pleats decorated long skirt apron back apron knot belt, scarf this type is the same with Dang Dynasty five dynasty of china Song, Kum Won, Myung Dynasty and our cos-tume of Poe-hae, and Shilla Dynasty.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
• /
• 2002.11a
• /
• pp.136-140
• /
• 2002

In this paper, newly constructed 5.6 ㎓ ring resonator by using a T-Junction and a parallel transmission line. The resonator's size reduced twice more than a current ring and a hair-pin resonator at this paper's center frequency The loaded Q value is 240∼250 at center frequency. also, It was explained by RLC equivalent equation for the resonator.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.18 no.9
• /
• pp.1315-1322
• /
• 1993

본 연구에서는 헤어핀 공진기를 이용하여 L대역 대역통과 MIC여파기를 설계하였다. 여파기의 크기를 줄이기 위해 헤어핀 공진기 간의 결합을 일반결합 대신에 안쪽견합 또는 혼합결합을 사용할 누 있다. 안쪽결합을 사용한 4개의 공진기로 된 여파기는 일반결합 여파기 보다 크기가 20~30% 감소되었다.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.20 no.4
• /
• pp.333-343
• /
• 2009

The BPF designed by the formula based on strip line shows the center frequency shift and distortion in filter response and this becomes more significant with higher frequency. In this paper, the novel design based on EM simulation is proposed. In the design, the filter is decomposed into individual resonators and, for each resonator, the reactance slope and the inverter values are measured and tuned to desired design values for a inverter BPF prototype. The filter composed with such resonators shows the desired filter response without further tuning. This is because possible effects of discontinuities and dispersion are included in the filter parameter extraction. The method can generally apply to all filters that can be transformed into inverter BPF prototype. The procedure is verified by designing a 5th-order SIR filter and quite general to adapt into the design of a parallel coupled line filter, and hair-pin filter.

• Journal of Advanced Navigation Technology
• /
• v.22 no.1
• /
• pp.27-30
• /
• 2018

In this study, a 40 GHz band pass filter(BPF) employing a hair-pin structure has been designed, fabricated, and characterized for millimeter-wave wireless communication applications. Using the 3 dimensional(3-D) electromagnetic(EM) tool and design equations of the hairpin BPF, the BPF was desgned on the 5 mil-thick Duroid substrate(RT5880) with a relative dielectric constant (${\varepsilon}_r$) of 2.2. The tapping point (t) of the U-shape resonator in the input and output port has been determined using extracted an external Q-factor ($Q_e$). The coupling coefficients between the other resonators are calculated by adjusting the physical dimensions for the desired response of the BPF. The fabricated BPF was characterized using probing method on a probe station. Its measured center frequency(fc) and fractional BW are 41.6 GHz and 7.43 %, respectively. The measured return loss is below -10 dB at the pass band and the insertion loss is 3.87 dB. The fabricated BPF is as small as $9.1{\times}2.8mm^2$.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.36 no.4A
• /
• pp.407-413
• /
• 2011

In this paper, the reduced size of broad bandpass filter with parallel coupled line structure is presented. This proposed filter can control bandwidth of narrow to broadband by adjusting the coupling coefficient. The conventional filter is operated with a narrow band. If a higher bandwidth is desired than the conventional narrow bandwidth, it is hard to realize due to the coupling coefficient between feeding line and resonator. In this paper, to overcome this limitation, a proposed bandpass filter is designed with reduced size due to SIR (Stepped Impedance Resonator), U-shaped open stub with hair-pin and vertical-type structure than conventional one, and it has characteristics of adjusting bandwidth freely as per quantity of coupling coefficient. The proposed bandpass filter that, experimental results of insertion and return losses are 0.42 dB and 24.5 dB with bandwidth of 60 % at the center frequency of 5.8 GHz, respectively.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.25 no.8B
• /
• pp.1493-1498
• /
• 2000

In this paper, we introduce a modified interference cancellation scheme to overcome MAI in DS-CDMA. Among ICs(Interference Cancellers), PIC(Parallel IC) requires the more complexity, and SIC(Successive IC) faces the problems of the long delay time. Most of all, the adaptive detector achieves the good BER performance using the adaptive filter conducted iteration algorithm. so it requires many iterations. To resolve the problems of them, we propose an improved adaptive detector that the received signal removed MAI through the sorting scheme and the cancellation method are fed into the adaptive filter. Because the improved input signal is fed into the adaptive filter, it has the same BER performance only using smaller iterations than the conventional adaptive detector, and the proposed detector having adaptive filter requires less complexity than the other detectors.

• The Transactions of the Korean Institute of Power Electronics
• /
• v.21 no.5
• /
• pp.381-387
• /
• 2016

Many efforts have focused on the improvement of power density and efficiency by downsizing the motor and inverter. Recently, Toyota, Honda, and GM realized that the compact-sized motor uses the hairpin structure with increased space factor. Reducing the maximum torque from high-speed technique also makes it possible to design the high-power density model. Toyota and Honda used the newly developed power semiconductor IGBT to decrease conduction loss for high-efficiency inverter. In particular, Toyota used the boost converter to increase the DC link voltage for high efficiency in low-torque high-speed region. Toyota and GM also used the double-sided cooling structure for miniaturization of inverter for high-power density.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.6 no.1 s.12
• /
• pp.38-46
• /
• 2007

In this paper an X-band low phase noise HBT oscillator using a planar type MMIC resonator is designed. The chip area of the proposed resonator shows a quarter of the conventional hair-pin resonator using distributed transmission lines. The measurement results show oscillation frequency of 8.295 GHz, the power output of 4.8 dBm, and phase noise characteristic of -106.8 dBc/Hz and -121.7 dBc/Hz at 100 kHz and 1 MHz offset frequencies respectively.