• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 하계종합학술대회 논문집(1)
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• pp.260-262
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• 2000

Printed microstrip antennas are known to have limitations in terms of bandwidth by the presence of the dielectric substrate. In this paper, to overcome these limitations, a broadband microstrip bow-tie antenna which has two dip point for high speed wireless LAN, fabricated on a Taconic substrate is designed and simulated. In simualted results, the return loss is two dip point which is -28.5dB at 5.68GHz and -27dB at 5.85GHz. The bandwidth of this antenna is 8.7％ about VSWR$\leq$2 and 5.9％ about VSWR$\leq$1.5.

• 한국전자파학회논문지
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• 제13권5호
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• pp.468-474
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• 2002

본 논문에서는 접지면에 원형 슬롯이 있는 양팔 마이크로스트립 스파이럴 안테나를 제안하였다. 제안한 안테나는 별도의 발룬(balun)회로 없이 평면 구조로 구현하였으며 하나의 안테나의 구조로부터 주빔이 안테나 평면에서 수직한 일반 스파이럴 안테나의 복사특성과 주파수 변화에 따라 주빔이 $\theta$와 $\phi$ 방향으로 일정하게 변하는 편심 스파이럴 안테나의 복사특성을 동시에 얻을 수 있다. 원형슬롯의 반지름이 23 mm일 때 2.5 GHz에서 3.3 GHz까지의 주파수 영역에서는 주빔이 안테나 평면에 대해 수직한 방향을 유지하며 그 이후 주파수가 증가함에 따라 주빔이 일정하게 기우는 편심 스파이럴 안테나의 특성을 가진다.

• 한국항행학회논문지
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• 제15권6호
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• pp.1008-1014
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• 2011

본 논문에서는 WLAN 대역과 WiMax 대역에서 통신을 가능하게 하기 위한 다중대역 프랙탈 마이크로스트립 패치 안테나를 설계 및 제작하였다. 제안된 안테나는 다중공진을 위해 공진주파수, 임피던스정합, 극성 및 방사패턴을 훌륭히 제어할 수 있으며 다중 독립 주파수를 만족시키기 위한 세 개의 반원의 프랙탈 패치를 삽입하였다. 제안된 구조는 반원의 프랙탈 구조가 연속적으로 이루어져 있는 형태의 안테나로써 하나의 반원이 하나의 대역을 나타내고 있다.

• 한국통신학회논문지
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• 제21권3호
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• pp.753-762
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• 1996

In this paper, aperture coupled stacked microstrip array antennas are proposed and their operating characteristics are analyzed based on analytical. In order to evaluate mutual coupling between slot-coupled microstrip patches in finite array, analysis uses the reciprocity theorem and the spectral domain Green's functions for dielectric slab in a moment method solution for the unknown patches and solts current distrbution. By introducing an N-port equivalent network, the impedance matrix of an affay of N-element slot-coupled patches is evaluated directly from its network current matix of order N$^{2}$, and it can be programmed to be run on a PC. Numerical results show mutual coupling, radiation pattern, active reflection coefficient versus scan angle, radiation efficiency and active element gain pattern.

• 전자공학회논문지A
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• 제33A권3호
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• pp.65-81
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• 1996

In this study forty-five X-bnd rectangular microstrip patch antennas fed by microstrip line using ${\lambda}$/4 transformer were fabricated on teflon substrates with low high permittivities and varous thickness (substrate thickness : 0.6 ~ 2.4 mm, permittivities : 2.15 ~ 10.0), and effects of permittivity and electrical thickness on antenna characteristics were studied with measured return loss (1/S$_{11}$) and resonant frequencies. When substrate electrical thickness was greater than 0.060 ${\lambda}_{0}$return loss was very good and genrally more than 20 dB, but resonance characteristics was somewhat unstable. The more than 0.088 ${\lambda}_{0}$ the thickness was, the more unstable it was. As a result, in the rest range except 12, 13 GHz we had very good mesured return loss iwth greater than 20 dB, and in the range 7 to 9 GHz resonant frequencies were within $\pm$2 % error, on ${\epsilon}_{r}$=5.0, height = 2.4 mm substrate.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2006년도 하계종합학술대회
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• pp.219-220
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• 2006

In this paper, we designed and implemented the Dual Band Dipole Antenna with Tapered Microstrip Balun for WLAN Access Point. Two dipole antennas with different resonant frequency and the antenna structure combined additional line were implemented for dual band performance. In order to feed the balun current, the tapered microstrip balun was used. Produced the Dual Band Antenna shows a special quality. The quality is that all VSWR is less than 1.5 in the 2.4GHz and 5GHz frequency bands in 802.11 standards, and it profits not less than 1.7dBi having typical Dipole Antenna pattern the very "a form of 8"pattern and Omni-directional pattern.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 ITC-CSCC -1
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• pp.175-178
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• 2000

The resonance characteristic of microstrip antenna with an airgap between the substrate layer and ground plane is investigated. The study is performed by using a rigorous Green’s function formulation in the spectral domain and Galerkin’s moment method calculation. The numerical convergence using sinusoidal basis functions, the unknown surface current distribution in the rectangular patch, is discussed. Numerical result for the effects of airgap and patch length on the complex resonant frequencies of the rectangular microstrip structure are also presented

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 추계학술대회 논문집
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• pp.195-198
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• 1999

A technique is investigated for achieving broadband properties by controlling the operation frequency of microstrip antennas. The control is achieved by applying DC bias to the microstrip antenna. Air gap antenna with PZT post is fabricated. by using in C-band. In the case of Air gap antenna, the variation of center frequency was about 16Mhz and the bandwidth was increased up to 123.3% at 15dB, 160.7% at 20dB than before applying DC bias respectively. The change property of frequency in air gap antenna is nearly the same the C-V property in PZT.

• Journal of electromagnetic engineering and science
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• 제18권2호
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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.

• 한국통신학회논문지
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• 제22권8호
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• pp.1740-1746
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• 1997

본 논문에서는 도파관 슬롯 결합 마이크로스트림 안테나를 마이크로스트림 안테나의 개선된 급전 구조로서 제안하고 해석을 수행하였다. 해석 과정에서 스트립과 슬롯 사이의 유전체 기판의 존재가 충분히 고려되었따. 안테나 특성 파악을 위해 스트립의 전류 분포와 슬롯의 자류 분포를 알아내기 위한 수치해석 방법으로 모멘트법과 공간 주파수 영역법이 사용되었다. 해석 결과, 제안된 구조는 개선된 특성과 대량 생산의 용이함으로 인하여 배열 안테나의 설계시 우수한 단위요소로 쓰일 수 있음을 확인하였다.