• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1990.06a
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• pp.813-816
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• 1990

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1996.06a
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• pp.592-596
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• 1996

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1998.10a
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• pp.587-590
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• 1998

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1993.10a
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• pp.587-590
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• 1993

• Proceedings of the IEEK Conference
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• 2000.09a
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• pp.741-744
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• 2000

본 논문에서는 고밀도 DVD(Digital Versatile Disc) 시스템(4.7GB～l5GB)을 위한 신호 검출기법을 제안하고 FPGA로 구현한다. 본 논문에서 제안하는 FDTrS/DF (Fixed Delay Trellis Search with Decision Feedback)는 트렐리스 구조를 사용하므로 FDTS/DF나 SSD/DF(Signal Space Detection with Decision Feedback)와 같이 이진 가지 구조를 사용하는 신호검출방식에 비해 더 나은 성능을 얻을 수 있다. 또한 FDTrS/DF는 한 단의 트렐리스 구조를 사용해 역추적을 하지 않으므로 하드웨어의 복잡도와 속도면에서 향상된 결과를 얻을 수 있다. 또한 본 논문에서는 하드웨어 구현 시 동작 속도의 향상을 위해 파이프라인 기법과, 계산량 감소를 위해 절대값 분기거리를 사용한다.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.19 no.3
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• pp.352-357
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• 2008

We present a space-time trellis coded OFDM system in slow fading channels. Generalized principal ratio combining (GPRC) is also analyzed theoretically in frequency domain. The analysis shows that the decoding metric of GPRC includes the metrics of maximum likelihood(ML) and PRC. The computer simulations with M-PSK modulation are obtained in frequency flat and frequency selective fading channels. The decoding complexity and simulation running times are also evaluated among the decoding schemes.

• Journal of IKEEE
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• v.11 no.4
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• pp.198-204
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• 2007

For parallel and serially concatenated trellis coded modulation (TCM), improved iterative decoding schemes with a simple mechanism are proposed and their performances are compared with those of conventional decoding schemes. Simulation results have shown that the proposed schemes have provided a considerable decoding gain in additive white Gaussian noise (AWGN) channels and Rayleigh fading channels, even if they can be implemented by a simple modification of conventional decoding algorithms.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.12 no.3
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• pp.417-424
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• 2001

This paper proposes new symbol mapping method that can enhance the performance of trellis coded M-ary PSK compared with conventional symbol mapping methods in AWGN environment. Since the basic criteria of TCM design is Maximum Euclidean distance in AWGN, conventional symbol mapping method keep this basic criteria. In this paper, proposed new symbol mapping method uses both Euclidean distance and Hamming distance to design, while conventional methods make use of only optimal Euclidean distance. New symbol mapping method show the better BER performance than the other through computer simulation and error equations.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2003.11a
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• pp.171-174
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• 2003

본 논문은 기존의 표준 8-VSB 방식의 DTV 수신 성능 개선을 위해 ATSC T3/S9에 제안되었던 기술 중에서 현재 새로운 표준안으로 채택이 유력시되는 Zenith/ATI의 Enhanced 8-VSB 방식과 Philips의 Pseudo 2-VSB 방식에 대해 살펴보고, 다양한 채널 환경에 대해서 전산 모의 실험을 실시하여 자 방식의 수신 성능을 비친, 분석하였다. 이중 스트림 기술을 사용하였을 때, 강인한 트렐리스 부호화를 거친 강인데이터의 성능 개선 정도와 강인데이터가 표준데이터에 미치는 성능 개선 정도를 SNR에 따른 트렐리스 디코더의 바이트 에러율을 통해서 비교, 분석하였다.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.47 no.3
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• pp.240-244
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• 2019

SOQPSK-TG which consists of differential precoder and CPM modulator was adopted as telemetry standard because of its high power and bandwidth efficiency. We proposed four-state Viterbi decoder for SOQPSK-TG. Reducing the trellis state to four was possible by simplifying frequency pulse of SOQPSK-TG to square pulse of symbol length 2 and combing this with differential precoder. Compared with conventional SOQPSK-TG receivers, computer simulation result shows about 1 dB performance improvement was achieved at BER of $10^{-5}$ in AWGN channel.