• Title/Summary/Keyword: Aperture-coupled

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Room Acoustic Properties of Coupled Rooms Connected by an Aperture in the Steady State Condition (정상상태조건에서의 개구부로 연결된 커플룸의 음향 특성)

  • Na, Hae Joong;Lim, Byoung-Duk
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.26 no.3
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    • pp.315-322
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    • 2016
  • Room acoustic properties of coupled rooms connected by an aperture has been analyzed using statistical acoustic model based on the diffused sound field assumption, which has limitation in dealing with the parameters such an room geometries and non uniform absorptivity of the boundary surfaces. In order to overcome these difficulties the acoustic diffusion model has been introduced, by which distribution of the acoustic energy density can be analyzed for various shapes and wall absorptivity. In this study acoustic properties of coupled rooms connected by an aperture(e.g. door) is analyzed using acoustic diffusion equation, which is solved numerically. The mean energy densities of two rooms obtained by the diffusion model are compared with those from the statistical model. The results show good agreement for various coupling aperture sizes and absorption coefficients. For a limiting case when the partition wall is substituted by an aperture and the two rooms eventually forms a single room, results of coupled room analysis using diffusion model show good agreement with those of a single room.

The Bandwidth Enhancement of an Aperture Coupled Microstrip Patch Antenna Using Variation of an Aperture Width (개구면 폭 변화를 이용한 개구면 결합 마이크로스트립 패치 안테나의 대역폭 확장)

  • Kim, Jae-Hyun;Koo, Hwan-Mo;Kim, Boo-Gyoun
    • Journal of the Institute of Electronics and Information Engineers
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    • v.52 no.1
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    • pp.48-58
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    • 2015
  • The bandwidth enhancement of an aperture coupled microstrip patch antenna(ACMPA) with a high permittivity feed substrate suitable for the integration with MMIC is investigated using variation of an aperture width. As an aperture width increases, the 10 dB return loss bandwidth increases due to the increase of the mutual resonance region between a patch resonance and an aperture resonance. The bandwidth of an ACMPA with extended aperture width is increased up to 35.3 % from 20.8 % of the ACMPA with an aperture of a typical aspect ratio 10:1. The degradation of the radiation characteristics of an ACMPA due to the increase of an aperture width is very small.

Field Configurations in Aperture-Coupled Microstrip Antenna Structure (개구 결합 마이크로스트립 안테나 구조에서의 필드 분포)

  • 조영기;고지환;이영순;허유강
    • Proceedings of the Korea Electromagnetic Engineering Society Conference
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    • 2002.11a
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    • pp.259-262
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    • 2002
  • The problems of electromagnetic coupling and radiation in an aperture-coupled microstrip antenna structure are discussed while focusing on the difference between two representative field configuration: parasitic-type and cavity-type. Based on the discussion, a critical look is taken at the validity of a previous description of the coupling mechanism of m aperture-coupled microstrip antenna.

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Electromagnetic Coupling Mechanism in the Aperture-Coupled and Feedline Gap-Coupled Microstrip Patch Antenna (Aperture와 Feedline Gap 결합으로 급전되는 마이크로스트립 패치 안테나의 전자기 결합 메커니즘)

  • Kim, Jong-Kyu;Yoon, Lee-Geun;Cho, Young-Ki
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.38 no.1
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    • pp.27-33
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    • 2001
  • This article describes an observation that the aperture coupling mechanisms in the aperture coupled microstrip antenna can be divided into two categories, cavity and parasitic types, depending on the separation between the microstrip patch and the ground plane. The similar phenomenon was observed in the relatively simple gap coupled microstrip antenna. The specific characteristics between two coupling mechanisms is discussed.

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A Subjective Study on the Reverberation Characteristics of Coupled Spaces (음향적으로 결합된 공간의 주관적 잔향감에 관한 연구)

  • Jeong, Dae-Up;Choi, Young-Ji
    • Journal of Korean Association for Spatial Structures
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    • v.8 no.3
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    • pp.65-73
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    • 2008
  • The present work deals with subjective assessments to propose the objective parameter related to the subjective attribute of reverberation in the coupled room varied the aperture opening size. A 1/10 scale model was built and used for the measurements and subjective assessments. For the subjective tests, binaural impulse responses(BIRs) were measured using a dummy head and the measured BIRs were convolved with anechoic recorded music for the presentation over the headphones. The results showed that the perceived reverberation was the largest in the aperture opening size 12.5%(1.97% of mail) room surface area)and decreased with increasing the aperture opening size over 25% (3.94% of main room surface area) in the main room coupled with the secondary reverberant room. In the main room coupled with the secondary absorptive room, there was no changes in the perceived reverberation up to the aperture opening size 6.25%(0.99% of main room surface area) and it gradually decreased with increasing the aperture opening site over 12.5%. The objective parameter, T30/T15, showed a very low correlation with the perceived reverberation in the coupled room varied the aperture opening size but showed a high correlation with a new objective parameter, T30/Tbp, proposed by the authors. Because the late part decay energy more rapidly increases with increasing the aperture opening site than the early and middle part decay energy, the LDT/EDT or T3/T1 is a better quantifier to measure double slopes in the coupled room than the T30/T15.

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Aperture Coupled Cylindrical Resonator Oscillator (Aperture Coupled 원통형 공동 공진기 발진기)

  • 나인주;이정해
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.14 no.2
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    • pp.119-126
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    • 2003
  • In this paper, a cylindrical cavity resonator oscillator with high Q factor is designed and fabricated to improve the phase noise characteristic. A cavity resonator is coupled to oscillating circuit using aperture hole. Measured results show that the cylindrical cavity resonator oscillator (CRO) for Ku-band has less phase noise than the dielectric resonator oscillator (DRO) with the same oscillating circuit. It has output power of +3.92 dBm at the center frequency 13.4015250 GHz and phase noise of -109 dBc/Hz at 100 kHz offset.

Design and Fabrication of a Microstrip Patch Antenna with H-shape Aperture-Coupled structure for PCS Repeater (H자형 개구 결합구조를 갖는 PCS 중계기용 마이크로스트립 패치 안테나 설계 및 제작)

  • Lee, Jung-Gi;Jeoung, Chan-Gwoun;Kang, Young-Jin
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.11 no.3
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    • pp.465-470
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    • 2007
  • This paper is designed and producted the microstrip patch antenna which used aperture coupled feed structure, and had a comparatively hish gain and headband characteristic with a PCS substitution repeater antenna. The proposed antenna transformed a coupled slot into a H-type in order to improve a characteristic of a general aperture coupled feed antenna. It is this H-type form slot reduces back lobe from the antenna backside at the same time that a coupling between a power feed and patches is iccreased, and to have maximized a gain of an antenna. As a result of having measured the antenna which the VSWR was 1.5 or below and tied up the gain than 7.5dBi in the $1750{\sim}1870$[MHz] that was a PCS substitution, and a beamwidth became in $80^{\circ}$ and radio waves shadow was local, but accomplishment did PCS mobile communication service in building me smoothly, but confirmed what practical use can become.

A Study on the Reverberation Characteristics of Coupled Spaces (음향적으로 결합된 공간의 잔향특성변화에 관한 연구)

  • Jeong, Dae-Up;Kim, Ji-Young;Choi, Young-Ji
    • Journal of Korean Association for Spatial Structures
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    • v.8 no.3
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    • pp.53-63
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    • 2008
  • In this study, the reverberation characteristics of coupled spaces were investigated using a scale model. Two rooms were connected through an acoustically transparent opening known as an aperture. The acoustic characteristics of the coupled room by varying three parameters, the aperture opening size, the absorption ratio between the two rooms and the locations of the secondary room, were measured and analysed. The results indicated that a reverberant secondary room, produced large variations of the acoustics in the main room and an absorptive secondary room was effective to provide systematic control of the acoustics in the main room. The reverberant secondary room should be located at the rear of the stage and the aperture opening ratio over 6.25% produced large variations of the acoustics in the main room. However, the aperture opening ratio over 25% had no effect on variations of the acoustics in the main room. The absorptive secondary room should be located at the rear of the audience areas and the aperture opening ratio over 3.13% produced large variations of the acoustics in the main room.

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Improvement of Band Pass Filter Using PBG and Aperture (Aperture와 PBG를 적용한 대역통과 여파기 성능개선에 관한 연구)

  • 이승재;서철헌
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.28 no.10A
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    • pp.847-852
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    • 2003
  • Apertures and PBG(Photonic Band Gap) has been employed on the ground plane in the coupled line filter simultaneously. In order to observe the maximum bandwidth, we used the line gap 0.2mm which is can be made in our lab. Band-pass filter type is four-stage coupled strip line filter. Teflon has been used for the substrate ($\varepsilon$$\sub$r/=3.2). The center frequency and the bandwidth are 2.18GHz and 230MHz, respectively. The bandwidth is broaden from 230MHz to 310MHz (80Mhz, about 34.7%) by aperture effect and harmonic frequencies are suppressed to 20-30dB by PBG effect. So the harmonic frequencies have been suppressed by the PBG effect and the bandwidth are broaden by aperture effect.

Effect of Feed Substrate Thickness on the Bandwidth and Radiation Characteristics of an Aperture-Coupled Microstrip Antenna with a High Permittivity Feed Substrate

  • Kim, Jae-Hyun;Kim, Boo-Gyoun
    • Journal of electromagnetic engineering and science
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    • v.18 no.2
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    • pp.101-107
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    • 2018
  • The impedance bandwidth and radiation characteristics of an aperture-coupled microstrip line-fed patch antenna (ACMPA) with a high permittivity (${\varepsilon}_r=10$) feed substrate suitable for integration with a monolithic microwave integrated circuit (MMIC) are investigated for various feed substrate thicknesses through an experiment and computer simulation. The impedance bandwidth of an ACMPA with a high permittivity feed substrate increases as the feed substrate thickness decreases. Furthermore, the front-to-back ratio of an ACMPA with a high permittivity feed substrate increases and the cross-polarization level decreases as the feed substrate thickness decreases. As the impedance bandwidth of an ACMPA with a high permittivity feed substrate increases and its radiation characteristics improve as the feed substrate thickness decreases, the ACMPA configuration becomes suitable for integration with an MMIC.