Miniaturized Fractal Patch Antenna on Various Substrate

Sika Shrestha,Young-Gon Kim,Dong-You Choi 한국정보기술학회 2013 한국정보기술학회논문지 Vol.11 No.8

The conventional geometry of patch antenna is modified in various ways for its size reduction. The proposed method presents the application of fractal geometry in patch antenna for its miniaturization. A simple space filling fractal, Sierpinski carpet is etched on edge-fed rectangular shaped patch antenna and is iterated up to 3rd order. These four antennas are designed in three substrates: FR4 (?<SUB>r</SUB>=4.7; δ=0.019), FR4 (?<SUB>r</SUB>=4.4; δ=0.02), and Teflon (?<SUB>r</SUB>=2.2; δ=0.0009). All designed antennas resonated at 2.45㎓ with satisfying return loss, significant gain and fine impedance matching. A comparative analysis of patch antenna on different substrates on the basis of size reduction, impedance bandwidth and gain is presented. Simulation results of Sierpinski carpet iterations on three substrates and their comparison with the generator shows significant size reduction, without affecting antenna performance such as reflection loss, impedance matching, and antenna gain. It is observed that gain is highest for the substrate with lowest relative permittivity having a trade-off of greater size and low impedance bandwidth.

Design of the UWB BandPass Filter of Microstrip CRLH-TL Metamaterial Cell Type with Improved Rejection Performance

강승택(Sungtek Kahng),주정호(Jeongho Ju) 대한전자공학회 2008 電子工學會論文誌-TC (Telecommunications) Vol.45 No.8

좌우현 합성 선로 메타재질구조 쎌 형식인 UWB 대역통과여파기의 저지특성을 향상시키기 위해, 메타재질특성을 유지하면서도 소형화라는 설계목적에 적합한 저역통과여파기 개념을 제안한다. 따라서 대역통과여파기 자체는 파장의 0.25배보다 훨씬 작게 만들어지고, 이는 인터디지틀 결합기와 접지된 스텁으로 구성되며, 전후에 대칭형 소형 저역통과 블록을 가진다. 설계결과는, 예상대로, 관내파장의 1/8의 크기, 대역폭 100%, 1㏈ 이하의 삽입손실, 평탄한 군지연, 우수한 반사손실 특성을 보인다. In order to enhance the rejection performance of the UWB bandpass filter based on the Composite Right- and Left-Handed Transmission-line(CRLH-TL) Metamaterial cell, we propose the lowpass filtering concept that fits into the design objectives : Keeping metamaterial property and miniaturization. So the bandpass filter itself is made far less than a quarter-wavelength and a pair of symmetric compa ct lowpass filtering blocks are placed before and after the center CRLH filter which comprises the interdigitated coupled lines and short-circuited stub. The design result will show the size of ‘guided wavelength/8’, the fractional bandwidth over 100%, the insertion loss much less than 1 ㏈, a flat Group-Delay and a good return loss performance, as expected.

A 20-GHz Miniaturized Ring Hybrid Circuit Using TFMS on Low-Resistivity Silicon

Lee Sang-No,Lee Joon-Ik,Yook Jong-Gwan,Kim Yong-Jun The Korean Institute of Electrical Engineers 2005 KIEE International Transactions on Electrophysics Vol.5C No.2

In this paper, a miniaturized ring hybrid circuit is characterized based on a thin film microstrip (TFMS) on low-resistivity silicon. In order to obtain low-loss characteristics, a polyimide layer with 50 $\mu$m thickness is spin-coated onto the silicon to be used for the substrate. First, propagation characteristics of TFMS lines consisting of the ring hybrid circuit are presented. Then, a ring hybrid circuit based on TFMS is featured by employing the triple concentric circle approach for miniaturization. Triple concentric circle lines with $\lambda$$_{g}$/4 or 3$\lambda$$_{g}$/4 line lengths are implemented on the surface of the polyimide by circularly meandering to reduce the circuit size of the designed ring hybrid. Good agreement between measured and simulated results is obtained.

Buddhist Ontology and Miniaturization: Enacting Ritualwith Nonhuman Agency

김연미 동국대학교 불교학술원 2017 International Journal of Buddhist Thought & Cultur Vol.27 No.2

This paper aims to theoretically explain the ways in which a ritual was enacted (or believed to be enacted) primarily through non-human agency in medieval Buddhism. Focusing on the miniature ritual altar installed in the relic depository of Chaoyang North Pagoda (1043–44), this paper addresses an academic lacuna in current ritual theories. Ritual theories almost always assume that ritual is a kind of human action, which makes it impossible to explain ritual spaces or objects that were designed to enact the ritual without human participation. The relic depository of Chaoyang North Pagoda was a completely sealed stone box that was clearly designed as a ritual space for chanting the Superlative Spell (Skt. Uṣṇīṣavijayā dhāraṇī). This ritual space occluded from human access contradicts with contemporary understandings of ritual. By illuminating the relic depository from the emic perspective of medieval Buddhists and applying anthropological theories, this paper offers theoretical explanations for conditions in which religious rituals were primarily enacted through non-human agency.

소형 선형 액추에이터 설계를 통한 확장현실 햅틱 컨트롤러 소형화에 관한 연구

고기남,문남미 차세대컨버전스정보서비스학회 2022 차세대컨버전스정보서비스기술논문지 Vol.11 No.2

확장현실에서 핸드 컨트롤러는 여러 종류의 센서를 사용하여 사용자의 움직임 및 물리적인 입력 정보를 인식하고, 사용자의 손과 손가락에 역감, 진동, 촉감 등의 감각을 제공하여 확장현실 콘텐츠의 몰입감을 높인다. 상용 핸드 컨트롤러는 사용자 인터페이스를 고려하여 핸드헬드 형태로 설계되고 있는데, 핸드헬드 컨트롤러는 구동 모듈, 제어 모듈, 배터리와 같은 부품을 포함하면서도 사람의 손으로 잡을 수 있어야 하므로 내부 설계 및 인체공학적 디자인이 중요하다. 본 연구에서는 다섯 개의 액추에이터를 사용하여 다섯 손가락에 역감 피드백을 제공하는 확장현실 컨트롤러 설계에 관해서 연구하였다. 컨트롤러 내부의 부피 비율이 높은 소형 액추에이터 구조를 재설계하고 이를 통합하여 햅틱 피드백 모듈 및 컨트롤러 외형을 재설계하여 햅틱 컨트롤러의 크기를 소형화하였다. 기존의 컨트롤러와 새로 제작한 컨트롤러의 엑추에이터 이동 거리 및 엑추에이터의 힘을 측정하여 비교하였으며, 새로 제작한 컨트롤러가 소형화되었음에도 기능적으로도 개선되었음을 보였다. In extended reality, a hand controller uses several types of sensors to recognize the user's movement and physical input information, and provides senses such as force feedback, vibration, and tactile to the user's hand and fingers to increase the immersion of an extended reality content. Commercial hand controllers are designed in a handheld form considering the user interface. Internal design and ergonomic design are important because handheld controlles must be capable of being held by a human hand while including many parts such as motor driving modules, control modules, and batteries. In this study, the design of an extended reality controller that provides force feedback to five fingers using five actuators was studied. A small actuator with a high volume ratio inside the controller was miniaturized, and the size of the haptic controller was miniaturized by redesigning the haptic feedback and controller exterior. The actuator movement distance and actuator force of the existing controller and the newly designed controller were measured and compared, and it was shown that the newd controller was functionally improved even though it was miniaturized.

Optimized Design of Low-power Adiabatic Dynamic CMOS Logic Digital 3-bit PWM for SSL Dimming System

Cho, Seung-Il,Mizunuma, Mitsuru,Yokoyama, Michio The Institute of Electronics and Information Engin 2013 IEIE Transactions on Smart Processing & Computing Vol.2 No.4

The size and power consumption of digital circuits including the dimming circuit part will increase for high-performance solid state lighting (SSL) systems in the future. This study examined the low-power consumption of adiabatic dynamic CMOS logic (ADCL) due to the principles of adiabatic charging. Furthermore, the designed low-power ADCL digital pulse width modulation (PWM) was optimized for SSL dimming systems. For this purpose, an ADCL digital 3-bit PWM was optimized in two steps. In the first step, the architecture of the ADCL digital 3-bit PWM was miniaturized. In the second step, the clock cut-off circuit was designed and added to the ADCL PWM. As a result, compared to the original configuration, 60 transistors and 15 capacitors of ADCL digital 3-bit PWM were reduced for miniaturization. Moreover, the clock cut-off circuit, which controls wake-up and sleep mode of ADCL D-FFs, was designed. The power consumption of an optimized ADCL digital PWM for all bit patterns decreased by 54 %.

저역통과 필터 특성을 가진 계단 형 임피던스 대역통과 필터의 설계

오송이,황희용 강원대학교 정보통신연구소 2013 정보통신논문지 Vol.17 No.-

In this paper, a band pass filter(BPF) using stepped-impedance resonators(SIR) with low pass filter(LPF) characteristics is proposed. A SI-LPF designed based on the standard SI-LPF design procedure is folded as a compactly rectangle. The merits of this structure are the adjustabilities of the LPF characteristic by changing the resultant slots parameter after folding the SI-LPF for miniaturization. Also, a very compactly BPF is desinged using two SDRs with characteristics of LPF; hence, it has the wide stopband (about 3f〇). In future, the proposed BPF will be used in the mi-crowave systems.

삼각 패치형 인공 전송 선로를 이용한 브랜치 라인 하이브리드

오송이(Song-Yi Oh),황희용(Hee-Yong Hwang) 한국전자파학회 2012 한국전자파학회논문지 Vol.23 No.7

본 논문에서는 슬롯을 갖는 삼각 패치형 인공 전송 선로를 이용한 브랜치 라인 하이브리드를 제안한다. 제안된 인공 전송 선로는 구조가 콤팩트하고 슬롯의 파라미터들을 변화시킴으로써 선로의 특성 임피던스와 전기적 길이를 조절하는 데 용이하여 일반적인 전송 선로를 소형화시키는 데 유용하다. 제안된 브랜치 라인 하이브리드는 이러한 직각 삼각형의 인공 전송 선로들을 이용하여 구현되었기 때문에 공간의 활용도가 높고 소형화되었다. 제작된 3 ㏈ 브랜치 라인 하이브리드는 중심 주파수 2.45 ㎓의 15 % 대역폭 내에서 ±0.5 ㏈의 결합도 변화특성과 두 출력 포트 간 91°±4°의 위상차 특성을 보였다. 또한, 제안된 브랜치 라인 하이브리드의 크기는 일반적인 브랜치 라인 하이브리드 크기의 38 %이다. A branch-line hybrid using microstrip artificial transmission lines(ATLs) with slotted-triangular patches is proposed. The proposed artificial transmission line is compact in structure as well as easy to adjust the characteristic impedance and electrical length of equivalent transmission line by changing the slot’s parameters; hence, it is useful for miniaturizing conventional transmission lines. The designed branch-line hybrid, because of the use of the right angled isosceles triangular shaped artificial transmission lines as building blocks, has no useless empty space, and hence optimally miniaturized. A fabricated 3 ㏈ branch-line hybrid shows the coupling variation of ±0.5 ㏈ and the phase difference between two output ports of 91°±4° within 15 % bandwidth at 2.45 ㎓ center frequency. The size of proposed branch-line hybrid is only 38% of the conventional branch-line hybrid.

삼각패치형 저역 통과 여파기의 구현

오송이(Song-Yi Oh),황희용(Hee-Yong Hwang) 한국전자파학회 2012 한국전자파학회논문지 Vol.23 No.3

본 논문에서는 계단 임피던스를 갖는 삼각패치형 5단 저역 통과 여파기를 제안한다. 제안된 구조는 일반적인 계단형 임피던스 저역 통과 여파기를 직각 이등변 삼각형으로 접어 구현한 구조로서, 설계법은 기존의 계단형 임피던스 여파기와 동일하다. 또한, 기존 계단형 임피던스 여파기와 다르게, 이 구조는 콤팩트하게 접히면서 생성된 slot들에 의하여 여파기의 차단 주파수 및 차단 대역폭과 감쇠극 특성을 조절할 수 있는 장점을 가지고 있고 또한, 소형화에 유리하다. 제작된 여파기는 13.75 mm×6.875 mm의 크기로 일반적인 계단형 임피던스 여파기에 비해 24.4 %의 크기가 감소되었다. 측정 결과, 통과 대역에서 -10 dB 이하의 반사 손실과 차단 대역에서 -10 dB 이하의 삽입 손실을 보였고, 약 3f_c까지 차단되었다. In this paper, an stepped-impedance low pass filter(SI-LPF) of triangular-patch type is proposed. A SI-LPF designed according to the standard SI-LPF design procedure is folded as a right angled triangle. The figure of merits of this structure are the adjustabilities of the cut off frequency, the stopband and the attenuation pole frequency of the proposed LPF by varying the resultant slots after folding the SI-LPF compactly for miniaturization. The size of the fabricated LPF is 13.75 mm×6.875 mm, which is 24.4 % reduced one compared to that of the conventional SI-LPF. The measured results of the LPF show return loss of less than -10 dB at passband, insertion loss of less than -10 dB at stopband and wide stopband from 3.5 GHz to 10 GHz (about 3f_c).

이층 기판 결함접지구조 전송전로를 이용한 소형 저역통과여파기 설계

김용주(Young Joo Kim),서동호(Dongho Seo),윤원상(Won-Sang Yoon),한상민(Sang-Min Han) 대한전기학회 2020 전기학회논문지 Vol.69 No.12

A compact double-layered DGS lowpass filter is proposed with miniaturized DGSs. The double-layered structure is composed of a conventional DGS microstrip line attaching a thick dielectric slab of a high dielectric constant, which makes a higher effective dielectric constant on a DGS pattern. The compact DGS lowpass filter is designed with miniaturized DGSs. The equivalent circuit is extracted from single DGSs on double-layered lines. The fifth-state lowpass filter with three DGSs has been implemented and compared with theoretical circuit models and electromagnetic simulated results. From the experimental results, the proposed double-layered DGS lowpass filter has shown good agreements to the design analysis and compared with a conventional DGS filter without an additional lower dielectric substrate to verify miniaturization.