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Performance of CEFSK Systems in Nonlinear Channel Environments (비선형 채널 환경에서 CEFSK 시스템의 성능)

  • Lee, Kee-Hoon;Choi, Byeong-Woo;Shin, Kwan-Ho;Seo, Jong-Soo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.38A no.1
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    • pp.79-87
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    • 2013
  • A new modulation technique - correlative encoded FSK (CEFSK) - for use in power and bandwidth limited digital communication system is proposed. CEFSK is free of ISI and generates output signals which have a smooth and continuous phase transition and a reduced envelope fluctuation by keeping correlation between amplitude and phases of two subsequent symbols. In comparison to conventional one-bit differential detected (1DD) GFSK, the performance of the 1DD-CEFSK in a non-linearly amplified (NLA) channel impaired by additive white Gaussian noise (AWGN), ISI and IM, is analyzed via computer simulation. The simulation result shows that, in an NLA single-channel, 1DD-CEFSK provides a signal-to-noise ratio (SNR) advantage of up to 1.2dB and 0.8dB at BER of $1{\times}10^{-4}$ when input back-off (IBO) of HPA is -1.0dB and -3.0dB, respectively. For the same channel environment with multi-channel, 1DD-CEFSK outperforms 1DD-GFSK by 1.1dB in SNR, regardless of the value of IBO.

A Novel Fixed-Complexity Signal Detection Technique Using Lattice Reduction for Multiple Antenna Systems (다중 안테나 시스템을 위한 고정된 연산 복잡도를 갖는 격자 감소 기반 신호 검출 기법)

  • Yang, Yusik;Suh, Dong Geun;Kim, Jaekwon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.38A no.1
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    • pp.10-18
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    • 2013
  • Recently, a fixed complexity LR(fcLR) technique was proposed. Also QR-LRL signal detection method was proposed in which all constellation symbols are tried as the symbol corresponding to the least reliable layer (LRL), thereby achieving high error performance. In this paper, we combine these two efficient methods to propose a novel detection method. When the LRL is disregarded in the process of LR, the worst case complexity of LR is significantly reduced. Also, the proposed method is shown to be superior to the conventional fcLR-based detection method from the perspective of error performance. Simulations are performed to demonstrate the efficacy of the proposed method.

A Study on the Analysis of Major Tarot and the Making of Beauty Tarot Design (메이저 타로카드 분석 및 뷰티타로카드 디자인제작 연구)

  • Lim, Doo-Kyu;Lim, Hee-Kyung
    • Journal of the Korea Convergence Society
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    • v.9 no.7
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    • pp.251-257
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    • 2018
  • Since the tarot is establishing itself as a play culture arousing the fun and curiosity from people, this study is intended to arrange an opportunity for people to have more interest in the beauty by the beauty tarot card. Hereby, the beauty tarot card was interpreted by applying the kabala focusing on the major Arcana card, a core element of the universal weight tarot, which was the basis of the tarot card based on the precedent study. A tool was made that the beauty tarot dot could be used as a counseling method by applying the beauty tarot card to 22 major Arcana after changing 4 elements: fire, water, air, and ground that were basic symbols of universal tarot card into the brush, foundation, eyebrows, and shadow, regarding them as the beauty-related symbol. It is thought that the made beauty tarot card will enable the tarot readers or relevant profession to give beauty-related counsel usefully to people interested in the tarot card. It is expected that the interest and concern for the beauty tarot card heightens, and the tarot cards according with various aesthetic domains such as the makeup, hair, skin, and nail art are produced in the future.

Analysis of Interrelation between Image and Text as Fusion Relationship -Through Advertising Production Class- (융합적 관계로서의 이미지와 텍스트의 상호관계성 분석 연구 -광고 제작 수업을 통하여-)

  • Seo, Hwa-Jung;Huh, Yoon Jung
    • Journal of the Korea Convergence Society
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    • v.9 no.7
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    • pp.155-162
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    • 2018
  • This study explores the relationship between images and texts through advertising production using images and texts, and analyzes the student works with the semiotics of Roland Barth. Since Barth emphasized the interpreter's interpretation rather than the producer's intention in his work, he interpreted the work as a receiver. It was analyzed in terms of socio-cultural meaning of what students produced in the works. A total of 64 classes were held for the first two classes in D high school. The results of analyzing students' works after the advertisement production class are as follows. First, as a result of analyzing Barth 's myth structure model, advertisement image and text are symbols and have meaning. Second, advertising image and text complement each other and have the characteristic of interrelationship that constitutes meaning. Third, By attracting the socio-cultural implications inherent in the students' advertising, their values and interests could be discovered.

Improving The Performance of Turbo Code by Optimizing QAM Constellation (QAM 변조방식의 성상도 최적화를 통한 이진 터보 부호의 성능 개선)

  • Lee, Keun-Hyung;Lee, Ji-Yeon;Kang, Dong-Hoon;Oh, Wang-Rok
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.46 no.7
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    • pp.39-44
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    • 2009
  • It is well-known that the performance of turbo codes can be improved by allocating different energies per code symbol. In this paper, based on this observation, we propose a joint encoding and modulation scheme for quadrature amplitude modulated turbo code systems. In the proposed scheme, the amount of energy difference between the turbo coded symbols is optimized by optimizing the constellation of quadrature amplitude modulation (QAM). The proposed scheme offers better coding gain compared to the conventional combination of binary turbo code and QAM at the bit error rate of 10$^{-5}$. Also, the performance of binary turbo codes with the proposed QAM constellation for various code symbol mapping strategies are verified.

MIMO-OFDM Receiver Algorithm with the Capability of Inter-cell or Inter-sector Interference Cancellation (인접 셀 혹은 인접 섹터 간섭제거 능력을 갖는 MIMO-OFDM 수신 알고리즘)

  • Ko, Kyun-Byoung
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.46 no.4
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    • pp.1-7
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    • 2009
  • In this paper, the author presents the MIMO(Multi-Input Multi-Output) receiver algorithm with the capability of inter-cell or inter-sector interference cancellation over multi-antenna OFDM(Orthogonal Frequency Division Multiplexing) systems. As contrast with the previous research dealing with the filtering scheme at the time domain, the proposed algorithm is presented as the pre-filtering scheme which can be applicable to the frequency domain. Note that the proposed one can be implemented only by pilot symbols which are used in the channel estimation. In addition, it is analytically confirmed that the proposed scheme can be applied for either MIMO( C-SM(Collaborative-Spatial Multiplexing)) interference or SIMO(Single-Input Multi-Out) interference. The proposed receiver algorithm is verified by simulations over UL-PUSC SR off in IEEE 802.16e standard. From simulation results, it is confirmed that the proposed one can be applicable regardless of the kind of interference. Furthermore, it is verified that the performance is guaranteed even under Ole severe effect of interference and the improvement of system throughput is guaranteed.

Performance Improvement of Low Complexity LS Channel Estimation for OFDM in Fast Time Varying Channels (고속 시변 채널 OFDM을 위한 저복잡도 LS 채널 예측의 성능 개선)

  • Lim, Dong-Min
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.49 no.8
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    • pp.25-32
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    • 2012
  • In this paper, we propose a method for improving the performance of low complexity LS channel estimation for OFDM in fast time varying channels. The CE-BEM channel model used for the low complexity LS channel estimation has a problem on its own and deteriorates channel estimation performance. In this paper, we first use time domain windowing in order to remove the effect of ICI caused by data symbols. Then samples are taken from the results of the LS channel estimation and the effects of the windowing are removed from them. For resolving the defect of CE-BEM, the channel responses are recovered by interpolating the resultant samples with DPSS employed as basis functions the characteristics of which is well matched to the time variation of the channel. Computer simulations show that the proposed channel estimation method gives rise to performance improvement over conventional methods especially when channel variation is very fast and confirm that not only which type of functions is selected for the basis but how many functions are used for the basis is another key factor to performance improvement.

Channel Estimation Method Using the Correlation in the High-Speed Wireless Transmissions (고속 무선 전송에서 상관관계를 이용한 채널 추정방식)

  • Lee Joo-Hyoung;Kim Joo-Kyoung;Kim Jae-Moung
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.4 no.1 s.6
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    • pp.63-71
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    • 2005
  • This paper proposes the channel estimation method robust to severe frequency selective fading channels in O%M system using wide bandwidth for the high data rate transmission. DDCE, which uses data between the high correlated symbols, is usually used for channel estimation in the slow fading channels. DDCE can get high gains in the non-selective channels. As the bandwidth of system gets wider, it becomes more severe frequency selective fading environments so that the reliability of data becomes lower and error flow is occurred. FE method, this paper proposed, uses the relation between sub-carriers of OFDM in frequency selective fading channels so FE method gets some gains by adapting the power value at a target frequency to the mean value of channel estimated values of adjacent sub-carriers. Because FE uses only preamble unlike DDCE using data, it is independent of data rate related to the reliability of data and the number of multipath. Consequently, FE can obtain considerable gains in the wideband systems where the errorflow of DDCE is occurred, and FE is applicable to frequency selective fading environments.

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A Study on Convolutionally-Coded Overlapped Multicarrier DS-CDMA Systems in a Multipath Fading Channel (다중경로 페이딩 채널에서 콘볼루션 채널코딩을 적용한 중복된 멀티캐리어 DS-CDMA 시스템에 관한 연구)

  • Oh, Jung-Hun;Hwang, Yong-Nam;Youm, Joeng-Won;Kim, Ki-Doo
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.37 no.1
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    • pp.76-87
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    • 2000
  • Multicarrier DS-CDAM is an effective approach to realize wideband CDMA system in a multipath fading channeal. In this paper, we propose a cinvolutionally-coded overlapped multicarrier DS-CDMA system, and show the performance improvement by comparing with conventional multicarrier DS-CDMA system. We consider the case of 50% overlapping with the adjacent subband to utilize the transmission bandwidth more efficiently. In the proposed multicarrier system, each of the rate 1/M convolutionally-encoded symbols is also 1/R repetition coded and transmitted using overlapped multicarriers and we may obtain the coding gain and frequency diversity effect, simultaneously. We also analyze the possibility of reduction in total MUI by considering a raised-cosine wave-shaping filter having a roll-off factor (0< ${\beta}{\le}1$). It will be shown that the proposed system outperforms the multicarrier DS-CDMA system in $^{[3]}$.

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The Application of Jean Michel Basquiat's Graffiti to Fashion Painting (Jean Michel Basquiat의 그래피티(Graffiti)를 응용한 패션페인팅)

  • Jang, Ae-Ran;Ko, Eun-Suk
    • Journal of the Korean Home Economics Association
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    • v.44 no.6 s.220
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    • pp.23-34
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    • 2006
  • Graffiti has been recognized as an art form since the influence of free, black culture and Neo-Expressionism in the 1980s, though Graffiti remains the subject of controversy both inside and outside the school Modem Art. Jean Michel Basquiat is the most famous Graffiti artist of the '80. He was regarded as the genius and star of American art, leaving a lot of experimental and creative works during his short, 9-year, creative period. In his works, Basquiat well expressed the isolated and dark shadows in the U.S., the pursuit of self identification, the purpose of expression and the epochally social phenomenon. The purpose of this study is to investigate the application of Jean Michel Basquiat's Graffiti to fashion painting. To achieve this purpose, we present a lot of fashion painting works which apply Jean Michel Basquiat's Graffiti by focusing on autographic experience, racialism, cartoon themes, monely value, and anatomical death in the characteristics of Basquiat's works. Through this process, we can express and apply Basquiat's Graffiti to fashion painting by analogizing the themes and modeling the methods of his works, such as childish and simple features, intentionally wrong spellings and sentences, and symbols of death including skeletons, intestines, bones and teeth. In addition, Basquiat's techniques are examined in this study, including the representational handling of a brush, primitive and strong colors, and maximized shape. This study found that fashion painting can juxtaposes art and fashion by expressing Jean Michel Basquiats' Graffiti.