• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.1
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• pp.164-171
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• 2008

Adaptive equalizers are inevitable schemes in digital communication systems for compensating the transmission channel distortion. Additionally, to obtain the required BER(Bit Error Rate), the adaptive algorithms appropriate to the mobile communication channels are required. In this paper, we propose the NPDFE (Noise-Predictive Decision Feedback Equalizer) for communication systems performance improvement in mobile communication channels. The performance of the proposed NPDFE with QPSK (Quadrature Phase Shift Keying) is simulated under AWGN (Additive White Gaussian Noise), Ricean fading, ETSI (European Telecommunications Standards Institute) fading, and Rayleigh fading channels. The equalizers used in simulations are a LE (Linear Equalizer), a DFE (Decision Feedback Equalizer), and a NPDFE. Moreover, the equalizer performance criterion of the QPSK is the BER.

• KIPS Transactions on Computer and Communication Systems
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• v.8 no.11
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• pp.251-262
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• 2019

In this paper, we propose a simulator that provides various algorithms of RBF networks on neuromorphic chips. To develop algorithms based on neuromorphic chips, the disadvantages of using simulators are that it is difficult to test various types of algorithms, although time is fast. This proposed simulator can simulate four times more types of network architecture than existing simulators, and it provides an additional a two-layer structure algorithm in particular, unlike RBF networks provided by existing simulators. This two-layer architecture algorithm is configured to be utilized for multiple input data and compared to the existing RBF for performance analysis and validation of utilization. The analysis showed that the two-layer structure algorithm was more accurate than the existing RBF networks.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2014.10a
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• pp.540-542
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• 2014

The Universal Plug and Play (UPnP) specification permits networked devices to discover each other and to provide diverse services in the home network environment. Recently, new paradigms such as mobile connected computing, cloud-based service delivery, smart device content sharing, and Internet of Things (IoT) have emerged, but the home network based UPnP shows functional limitations in supporting such paradigms. To support them, the UPnP Forum has recently extended the capabilities of the existing UPnP, calling it UPnP+. In this paper, the UPnP Device Architecture V2.0 (UDA 2.0), which forms the basis of UPnP+, is presented. We present how UDA 2.0 enables the expansion of the home network to wide-area networks and non-IP device domains.

• Current Photovoltaic Research
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• v.7 no.3
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• pp.65-70
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• 2019

As a demand of higher power photovoltaic modules, shingled, multi-busbar, half-cell, and bifacial techniques are developed. Multi-busbar module has advantage for large amount of light havesting. And, half-cell is high power module for reducing resistive losses and higher shade tolerance. Recently, researches on multi-busbar is focused on reliability according to adhesion and intermetallic compound between Sn-Pb solder and Ag electrode. And half-cell module is researched to comparing with full-sized cell module for structure difference. In this study, we investigated the factors affecting to efficiency and adhesion of multi-wires half-cell module according to wire thickness, solder thickness, and flux. The results of solar simulator and peel test was that peel strength and efficiency of soldered cell is not related. But samples with flux including high solid material showed high efficiency. The results of FE-SEM and EDX line scan on cross-section between wire and Ag electrode for different flux showed thickness of solder joint between wire and Ag electrode is increasing through solid material increasing. Flux including high solid material would affect to solder behavior on Ag electrode. Higher solid material occurred lower growth of IMC layer because solder permeate to sider of wire ribbon than Ag electrode. And it increased fill factor for high efficiency. In soldering process, amount of solid material in flux and solder thickness are the factor related with characteristic of soldered photovoltaic cell.

• Science & Technology Policy
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• v.15 no.5 s.155
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• pp.14-26
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• 2005

• The Optical Journal
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• v.9 no.4 s.50
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• pp.66-68
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• 1997

• Electronics and Telecommunications Trends
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• v.10 no.3 s.37
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• pp.133-138
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• 1995

이동통신서비스의 보급확대에 따른 통신용단말기의 수요가 증가하고 있으나 단말기용 핵심부품은 일본 등 선진국에서 전량 수입에 의존하고 있다. 이중 마이크로파용 유전체를 이용한 필터의 경우 안테나 듀플렉서, RF 필터 등으로 이용되고 있으며, 소형화, 고기능화가 이루어지고 있다. 이 고에서는 이동통신용 핵심 부품인 이러한 유전체 필터의 소형화 추이 및 기술 동향을 살펴보고 국내 동향과 문제점 및 대책을 결론으로 제시하였다.

• Electronics and Telecommunications Trends
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• v.9 no.3
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• pp.103-115
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• 1994

미연방통신위원회(FCC)에서는 무선전파를 사용하는 장비 및 부품들은 사용에 앞서 해당 기술기준에 적합한지를 인증받도록 하고 있다. FCC가 규정하고 있는 무선전파를 사용하고 있는 기기들에 대한 인증은 확인, 형식승인, 신고, 형식인정, 검증 등으로 분류된다. 본 고는 FCC의 전파응용기기 및 부품에 관한 인증제도를 조사 분석하여 향후 국내의 무선통신 기기들에 대한 인증제도의 확립 및 시험 방법 연구에 보탬이 되고자 한다.

• Electronics and Telecommunications Trends
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• v.26 no.4
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• pp.105-114
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• 2011

이동통신 및 위성통신 분야에 있어서 무선통신기술은 무선환경에서 신호를 보내고 받는 기능을 수행하는 중요한 분야이다. 이러한 무선통신 분야에서 송수신단을 구성하는 송수신 부품은 RF 시스템의 성능을 좌우한다. 특히, 위성통신 분야에서 신뢰성을 획득하기 위해서는 고집적화와 소형화를 통한 경쟁력 확보가 필수적인데 이를 위한 기술이 MMIC이다. MMIC 기술이란 반도체 공정을 이용하여 RF 부품을 설계하고 제작하는 기술로써 본 고에서는 MMIC 기술 소개와 이동통신 및 위성분야에서의 MMIC 기술 동향과 개발 현황, 앞으로의 전망을 개괄적으로 서술하고자 한다.

• Electronics and Telecommunications Trends
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• v.9 no.1
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• pp.149-157
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• 1994

위성통신, 이동통신 등의 통신 시스템의 보급이 활발해짐에 따라 통신용 부품의 기술 개발이 한층 시급해지고 있다. 본 고에서는 이동통신용 단말기 및 기지국 RF 회로의 필수적인 부품인 아이솔레이터, 서큘레이터 등에 사용되는 기본 재료인 페라이트의 재료적 성질, 제조 공정 및 각국의 기술 현황에 대해 알아보고자 한다.