• Current Optics and Photonics
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• 제4권4호
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• pp.373-379
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• 2020

In this study, we investigate terahertz (THz) generation by a photoconductive antenna with electrodes in the shape of split-ring resonators. According to our theoretical investigation based on a lumped-circuit model, the inductance of this electrode structure leads to resonant behavior of the photo-induced current. Hence, near the resonance frequency the spectral components generated by a resonant photoconductive antenna can be greater than those produced by a non-resonant one. For experimental verification, a resonant photoconductive antenna, which possesses a resonance mode at 0.6 THz, and a non-resonant photoconductive antenna with stripe-shaped electrodes were fabricated on a semi-insulating GaAs substrate. The THz generation by both of the photoconductive antennas demonstrated a good agreement with the theoretically expected results. The observed relationship between the resonant electrodes of the photoconductive antenna and the generated THz spectrum can be further employed to design a narrow-band THz source with an on-demand frequency.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.772-775
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• 2001

This paper investigated that resonant frequencies of microstrip patch antenna were frequency aigle when PZT were used as the antenna substrates. The resonant frequencies of the antenna using the piezoelectric substrate were able to be controlled by applied voltage. The frequency variation of the air gap antenna was 16MHz when the voltage variation was 12[KV/cm].

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집
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• pp.488-491
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• 2001

This paper investigated that resonant frequencies of microstrip patch antenna were agile when piezoelectric materials were used as the antenna substrates. The resonant frequencies of the microstrip antenna using the piezoelectric substrate. The microstrip patch antenna made of Quartz substrate was designed and fabricated by Ensemble v 7.0 simulator. The experimental problem was compensated by Ensemble v 7.0

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 춘계학술대회 논문집 전자세라믹스 센서 및 박막재료 반도체재료 일렉트렛트 및 응용기술
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• pp.164-167
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• 2000

This paper investigated that resonant frequencies of microstrip patch antenna were tunable when piezoelectric materals were used as the antenna substrates. The resonant frequencies of the air-gap antenna using the piezoelectric substrate were able to be controlled by applied AC voltage. The frequency variation of the antenn was great when PZT were applied voltage of the resonant frequency.

• 한국통신학회논문지
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• 제14권5호
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• pp.435-441
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• 1989

링 급전 선로를 이용해서 두 slot 사이 공진 길이를 lambda/2혹은 로 한 한 3개의 Rectangular Microstrip Patch Antenna를 배열하고 제작하여 방사 패턴 특성을 고찰 했다. 링 급전 선로를 이용한 공진길이 lambda/2인 3개의 Rectangular Microstrip Patch Antenna의 경우 각 Patch Antenna 소자 방향에서 방사 패턴이 고찰되고, 공진 길이 lambda/인 3개의 Rectangular Microstrip Patch Antenna의 경우 각 Antenna소자 사이에서 방사 패턴이 고찰 되었다.

• Journal of electromagnetic engineering and science
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• 제13권3호
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• pp.189-191
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• 2013

This letter presents a compact metamaterial-based tunable zeroth-order resonant antenna. It is based on the double-negative unit cell with a function of tunable inductance realized by a varactor and impedance convertor in the shunt branch. The resonant frequency of the designed antenna ranges from 2.31 to 3.08 GHz, depending on the capacitance of the used varactor. Its size is very compact ($0.05{\lambda}_0{\times}0.2{\lambda}_0$) with a relatively wide tunable range of 29.1%. The impedance bandwidth of the antenna is from 20 to 50 MHz for the resonant center frequency. The measured maximum total realized gain is from -0.68 dBi (2.43 GHz) to 1.69 dBi (2.97 GHz). The EM-simulated and measured results are in good agreement.

• 한국정보통신학회논문지
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• 제8권3호
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• pp.535-540
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• 2004

본 논문에서는 CPW급전을 이용한 직사격형 슬롯안테나를 설계 방법에 대해 기술하였다. CPW 급전을 이용한 슬롯안테나는 간단한 구조를 가지고, 능동소자에 집적이 용이하다. 논문에 제시한 안테나는 다중 공진을 이용하여 광대역을 실현하고자 안테나의 구성을 내부패치안테나와 외부패치안테나 두 부분으로 하였다. 또한 안테나의 파라미터 변화와 내부패치 안테나의 위치 및 크기를 변화함으로써 다중공진안테나의 특성을 확인하였다. 제시된 안테나의 각각의 공진주파수 실험 결과치는 1,9GHz, 2.8GHz, 3,5GHz, 4,9GHz로 측정되었다. 각각의 공진주파수의 방사패턴에서 네 번째 공진주파수의 방사패턴이 TM11모드로 나타나므로 실제 제시한 직사각형 슬롯안테나는 3중공진주파수로 나타나는 것을 확인하였다.

• Journal of electromagnetic engineering and science
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• 제19권1호
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• pp.37-41
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• 2019

A stack-ring configuration is proposed for designing a dual-band circularly polarized (CP) antenna. Each ring generates different resonant frequencies. A good CP performance at both resonant frequencies is achieved by adjusting the relative distance between the two rings. The two operating bands are separated with a small frequency ratio of 1.07. Measured results show that radiation patterns with good CP characteristics are obtained at the two resonant frequencies.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 춘계학술대회 논문집 반도체 재료 센서 박막재료 전자세라믹스
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• pp.116-120
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• 2004

In this paper, we proposed a method to shift the resonant frequency by applying the electric field to microstrip patch antenna using piezoelectric substrates. We fabricated microstrip patch antenna using Y-cut LiNbO3, Quartz and FR-4 substrates. We designed and simulated the microstrip antennas by Ensemble V 7.0 of the simulation too1. We observed the resonant frequency by DC applied electric field in a microstrip patch antenna. When the electric field was 300 V/mm, the resonant frequency agile of Y-cut LiNbO3 microstrip patch antennas were 29 MHz. When the electric field was 400 V/mm, the frequency agile of X-cut, Y-cut and Z-cut quartz microstrip patch antennas were 55.2 MHz, 34.2 MHz and 28.0 MHz, respectively. However, when the electric field was 400 V/mm, the resonant frequency of FR-4 microstrip patch antenna does not changed. It was shown that the resonant frequency agile of Y-cut and Z-cut quartz microstrip patch antennas are due to piezoelectric phenomenon not to be permittivity.

• 한국정보통신설비학회:학술대회논문집
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• 한국정보통신설비학회 2007년도 학술대회
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• pp.419-422
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• 2007

This paper, designed UWB elliptical slot antenna and analysis based on the distribution of the electromagnetic fields pattern and resonant mode of designed antenna is presented. Designed antenna is fabricated on FR4 substrate with thickness of 1.524mm and relative dielectric constant 4.4. The measured bandwidth of $3.6GHz{\sim}20GHz$ for VSWR<2. Through the field pattern and resonant mode analysis that the slot antenna operates on a series of the multi-pole radiation based on TE modes matched to system impedance. And the perfect magnetic wall is along the axis of symmetry on the y-z plane. This result gives us an easier method to design the similar antennas, which is the impedance matching to the system impedance after once constructing a proper structure with a series of multi-mode resonances.