• Journal of electromagnetic engineering and science
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• 제19권1호
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• pp.20-30
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• 2019

A wide-band multiple-input multiple-output (MIMO) antenna with dual-band (2.4 and 5 GHz) operation is proposed for premium indoor access points (IAPs). Typically, an omni-directional pattern is used for dipole antennas and a directional radiation pattern is used for patch antennas. In this paper, both antenna types were used to compare their performance with that of the proposed $2{\times}2$ MIMO antenna. We simulated and measured the performance of the MIMO antenna, including the isolation, envelope correlation coefficient (ECC), mean effective gain (MEG) for the IAPs, and the throughput, in order to determine its communication quality. The performance of the antennas was analyzed according to the ECC and MEG. The proposed antenna has sufficient performance and excellent characteristics, making it suitable for IAPs. We analyzed the communication performance of wireless networks using the throughput data of a typical office environment. The network throughput of an 802.11n device was used for the comparison and was conducted according to the antenna type. The results showed that the values of the ECC, MEG, and the throughput have unique characteristics in terms of their directivity, antenna gains, isolation, etc. This paper also discusses the communication performance of various aspects of MIMO in multipath situations.

• 한국전자통신학회논문지
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• 제8권9호
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• pp.1285-1291
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• 2013

본 논문에서는 광대역 특성을 갖는 이중 원형 링 모노폴 안테나를 설계 및 제작 하였다. 제안된 안테나는 평면형 모노폴 형태를 기본으로 이중 원형 링과 접지면으로 구성되어 있으며 광대역 특성을 갖도록 설계하였다. 최적화된 파라메타을 얻기 위해 상용 툴(HFSS)을 사용하여 시뮬레이션 하였으며 안테나 성능에 민감하게 적용받는 파라메타를 찾아내서 최적화된 수치를 얻었다. 얻어진 최적화된 수치를 사용하여 제안된 안테나를 제작하였다. 제작된 안테나는 광대역 특성을 갖는 대역에서 반사손실, 이득, 방사패턴의 특성을 측정하였다. 측정결과, -10dB을 기준으로 4,530 MHz(2,510-7,040 MHz)의 광대역 특성을 얻었으며 주어진 이득은 최대이득 0.71~3.38 dBi 그리고 평균이득 -3.85~0.3 dBi을 얻었다. 측정된 방사패턴의 경우, 전체적으로 E면은 전방향성의 방사패턴을 갖고 있으면 H면은 다이폴 안테나의 전형적인 특성을 나타내고 있다

• 한국전자파학회논문지
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• 제16권2호
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• pp.204-210
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• 2005

본 논문에서는 RFID 칩 실장이 용이한 접지면이 첨가된 평면형 미엔더 형태의 평면형 다이폴 안테나를 이용 하여 UHF 대역에서 동작하는 RFID 태그용 안테나를 제안하였다. 태그의 크기를 명함 크기로 구현하기 위해서 안테나는 meander 형태로 구현하였으며, 안테나의 특성 개선을 위하여 T-정합법을 사용하였고, RFID 칩 실장이 용이한 구조를 구현하기 위해서 접지면을 첨가하였다. 논문에서 제안한 방법을 통하여 구현한 안테나의 크기는 $100\times60\;mm^2$이고, 유전체는 FR4를 사용하였다. 실험 결과 방사 패턴은 다이폴 안테나와 같이 전 방향(omnidirectional) 특성이며, 중심 주파수는 427 MHz, -10 dB 반사 손실 대역폭은 8 MHz, 최대 반사 손실은 21 dB이다. 따라서 본 논문에서 제안한 방법을 이용하여 RFID 칩 실장이 용이한 RFID 태그용 안테나를 구현할 수 있다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2007년도 추계학술대회논문집
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• pp.987-990
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• 2007

The accuracy of sound strength (G) measurement method in ISO 3382 has been questioned. One of the main reason is the difficulty in measuring a reference sound level in an anechoic chamber with the same set-up which was applied for the actual hall measurements. In the present paper, an in-situ measurement method for G was proposed by investigating the present G measurement method shown in ISO 3382. In addition, the sound radiation characteristics of typical omnidirectional loudspeakers were investigated and Phi (O) of auto correlation function (ACF) parameters was also calculated from an actual music excerpt to characterize the sound energy distribution in concert halls.

• Journal of electromagnetic engineering and science
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• 제16권4호
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• pp.235-240
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• 2016

In this paper, a low-profile planar inverted-F antenna (PIFA) for ultrawideband (UWB) applications is proposed. The antenna consists of a PIFA and a ground plane with a slot. The addition of the slot not only improves the impedance matching of the PIFA but also forms an additional resonance. Therefore, the proposed antenna has a wideband characteristic covering the full UWB frequency range (3.1 GHz to 10.6 GHz) and a stable and nearly omnidirectional radiation pattern. The antenna also has a smaller volume and thickness compared to previous UWB PIFAs.

• ETRI Journal
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• 제35권6호
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• pp.1075-1083
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• 2013

This paper describes an ultra-wideband (UWB) antenna that uses a ring resonator concept. The proposed antenna can operate in the entire UWB, and the IEEE 802.11a frequency band can be rejected by inserting a notch stub into the ring resonator. The experiment results indicate that the measured impedance bandwidth of the proposed antenna is 17.5 GHz (2.5 GHz to at least 20 GHz). The proposed UWB antenna has omnidirectional radiation patterns with a gain variation of 3 dBi (1 dBi to 4 dBi).

• ETRI Journal
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• 제31권1호
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• pp.71-73
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• 2009

In this letter, novel antennas with two spiral elements are presented for ultra-wideband application. The original antenna consists of a T-shaped microstrip feed line, two spiral radiating elements, and a ground plane with two circular slots. It measures 30 mm ${\times}$ 40 mm ${\times}$ 1.6 mm. Spiral elements are used to increase the lower bandwidth limit. To further reduce the size of the antenna, the original antenna is cut in half by using the symmetry of the surface current distributions. The proposed antennas feature omnidirectional radiation patterns and good gain flatness.

• ETRI Journal
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• 제32권3호
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• pp.475-478
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• 2010

A multiband meandered monopole antenna is proposed for digital video broadcasting handheld (DVB-H), global positioning system, personal communications service, wireless broadband (Wibro), and wireless local area network (WLAN) applications. The proposed antenna consists of a meandered line, a shorted length strip line, and a conductor strip between a meandered line and a microstrip feed line. By tuning a short strip and a conductor, a multiband impedance matching is achieved. The proposed antenna has an omnidirectional radiation and yields an antenna gain of greater than -3 dBi in the DVB-H band and 4.5 dBi in the Wibro and WLAN bands. Details of the proposed antenna design and experimental results are presented.

• ETRI Journal
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• 제32권4호
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• pp.610-613
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• 2010

This letter presents the design of a novel multiband USB dongle antenna with a compact ground plane. The radiating patch is composed of a modified meander-line monopole and a shorted loop to generate a dual-broadband resonance. The proposed antenna supports WiBro, Bluetooth, WLAN, WiMAX, and S-DMB services. The total dimensions of the fabricated antenna are 10 mm ${\times}$ 45 mm ${\times}$ 1 mm, the most compact size among multiband USB dongle antennas reported to date. The measured 10 dB reflection loss bandwidths are 20.8% (2.24 GHz to 2.76 GHz) and 20.2% (4.86 GHz to 5.95 GHz). The measured peak gain is 2.97 dBi, and efficiency is higher than 58%. In addition, the radiation pattern approximates an omnidirectional pattern.

• 한국전자파학회논문지
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• 제15권1호
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• pp.89-95
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• 2004

본 논문에서는 광대역 특성을 가지면서 소형화가 용이한 다중 미앤더 스트립 모노폴 안테나를 제안하였다. 제안한 안테나는 미앤더 구조를 이용하여 대역폭을 크게 확장시킬 수 있으며, 높이를 줄여 안테나의 소형화를 실현하였다. 최근 주목을 받고 있는 UWB 통신 대역폭을 포함하는 2.9 ㎓∼10.85 ㎓의 넓은 대역폭을 얻을 수 있었으며, 전방향으로 동일한 이득을 갖는 우수한 모노폴 복사패턴을 갖는다.