http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Design of CFD Structured Microstrip Line Bandpass Filter
Yoon, Giwan,Chai, Dongkyu,Linh, Mai,Yim, Munhyuk The Korea Institute of Information and Commucation 2002 한국정보통신학회논문지 Vol.6 No.8
본 논문에서는 CFB 구조에 기반한 마이크로스트립 라인을 이용하여 커플링 개수가 3개인 가변 대역통과 필터를 제안한다. 바이어스 전압을 증가시키면 강유전체의 실효 유전율($\varepsilon$eff)이 감소하고, 감소된 실효 유전율은 중심 주파수를 높은 값으로 이동시킨다 설계된 필터는 $\varepsilon$eff이 13~10에 걸쳐, 반사 손실이 10 dB 이상, 삽입손실이 3.5 dB 이하, 3-dB 대역폭이 1.18 GHz 이하, 중심 주파수는 25.4 GHz에서 28.8 GHz까지 이동하므로 가변성은 3.4 GHz에 달하는 특성을 보인다. 필터의 크기는 7.0 mm ${\times}$ 5.0 mm ${\times}$ 0.5 mm이다. In this paper, a 3-coupled microstrip line tunable bandpass filter has been designed on the basis of a tonductoriFerroelectricfDielectric (CFD) structure. This tunable filter basically exploits the fact that the increase in the bias voltage leads to the reduction of the effective dielectric constant (eon). This reduced $\varepsilon$eff shifts the center frequency (fc) to the higher value. The characteristics of designed filter are as follows; Return loss (RL) is larger than 10 dB; Insertion loss (IL) is les.i than 3.5 dB: 3-dB bandwidth (BW) is less than 1.18 GHz fc can be tuned from 25.4 GHz to 28.8 GHz over the variation of $\varepsilon$eff, from 10 to 13. Therefore, the tunability comes up to 3.4 GHz. The dimension of the filter designed is 7.0 mm ${\times}$ 5.0 nm ${\times}$ 0.5 mm.
Munhyuk Yim,Buil Jeon,Giwan Yoon 대한전자공학회 2019 Journal of semiconductor technology and science Vol.19 No.2
In this paper, we present a tandem-type vertically integrated nanogenerator (TVING) device with five layers of alternately stacked thin films (AlN/ZnO/AlN/ZnO/AlN). The TVING device shows about twice larger output voltages than the conventional VING device with three layers of stacked thin films (AlN/ZnO/AlN). Moreover, the TVING device can be fabricated in a tandem-type structure simply through the vertical integration of two similar VING devices. This device will be usefully applied for biocompatible micro-energy harvesting systems.
Performance Analysis of Alamouti Scheme in Time-Varying and Spatially Correlated Channels
LEE, Eunju,PARK, Jaedon,YOON, Giwan The Institute of Electronics, Information and Comm 2010 IEICE TRANSACTIONS ON COMMUNICATIONS - Vol.93 No.10
<P>In this paper, we analyze the performance of the 2 × 1 Alamouti scheme suggested by Alamouti, composed of the transmit space-time code and the simple linear decoding processing, in perfectly time-varying and spatially correlated channels. We derive the closed-form probability density function (PDF) of output signal-to-noise ratio (SNR) and outage probability of the Alamouti scheme as a function of spatial correlation coefficient in the consideration of no correlation in time. We observe that the performance of the Alamouti scheme is severely degraded when the channels are time-varying and spatially correlated.</P>
Eunju Lee,Linh Mai,Giwan Yoon IEEE 2011 IEEE microwave and wireless components letters Vol.21 No.11
<P>In this letter, a new two-step annealing technique is presented that can more effectively improve the resonance characteristics of the film bulk acoustic wave resonator (FBAR) devices in terms of return loss, <I>Q</I>-factor, and effective electromechanical coupling coefficient (<I>K</I><SUB>eff</SUB><SUP>2</SUP>). In the case of the SMR-type FBAR devices, the use of this approach has considerably improved the resonance performance (~8000 of Q-factor value, ~ 2% of <I>K</I><SUB>eff</SUB><SUP>2</SUP>) at the operating frequency of ~1.8 GHz, as compared to the conventional annealing techniques.</P>
Average Bit-Error Rate of the Alamouti Scheme in Gamma-Gamma Fading Channels
Jaedon Park,Eunju Lee,Giwan Yoon IEEE 2011 IEEE photonics technology letters Vol.23 No.4
<P>Multi-input multi-output (MIMO) in free-space optics communications with subcarrier intensity modulation has been a big research issue due to the diversity gain of MIMO to mitigate the signal scintillation caused by the atmospheric turbulence. In this work, we have analyzed the performance of the Alamouti scheme in FSO links. Particularly, a power series expression of the average bit-error rate (BER) of the Alamouti scheme is derived in gamma-gamma fading channels. As a result, the Alamouti scheme could achieve a high signal-to-noise ratio (SNR) gain of 37 dB in a strong turbulence regime, and also a high SNR gain of 27 dB in a moderate turbulence regime over the no diversity at the BER of 10<SUP>-6</SUP>.</P>
A Highly Integrated 1-Bit Phase Shifter Based on High-Pass/Low-Pass Structure
In Sang Song,Giwan Yoon,Chul Soon Park THE INSTITUTE OF ELECTRICAL ENGINEERS 2015 IEEE Microwave and Wireless Components Letters Vol. No.
<P>This letter presents a highly integrated 1-bit 90 <SUP>°</SUP> phase shifter based on high-pass/low-pass structure for 60 GHz beamforming applications using a standard 65 nm CMOS process. In order to overcome the limitation of the conventional low-pass only phase shifter, the combination of high-pass/low-pass network was utilized as a 1-bit phase shifter. By integrating a high pass network into the low-pass network with low loss single-pole single throw (SPST) switches that adapt a resistive body floating technique, the proposed phase shifter achieves average 5 dB IL and less than ±0.18 dB of insertion loss flatness and 1 dB rms amplitude error over the whole band in a small chip area of 0.16 mm <SUP>2</SUP> including pads.</P>