• Title/Summary/Keyword: Truncated Type-II Hybrid ARQ

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Performance Analysis of Truncated Type-II Hybrid ARQ Scheme and Diversity using an Adaptive Modulation Systems in Interference & Fading Environment (간섭과 페이딩 환경에서 Truncated Type-II Hybrid ARQ 방식과 다이버시티 기법에 의한 적응변조방식의 성능 해석)

  • 강희조
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2003.10a
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    • pp.677-681
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    • 2003
  • 본 논문에서는 멀티미디어 통신시스템을 위한 적응변조방식을 제안하였으며, 성능개선 기법으로는 Truncated Type-II Hybrid ARQ 방식과 MRC 다이버시티 합성기법을 사용하였다. 적응변조방식은 변조레벨에 의해 조절되고, 심볼 지수는 나카가미 페이딩 파라미터 값에 따라 변화한다. 멀티미디어 통신 시스템의 성능 해석은 다중 사용자 상황에서 적응변조방식 만을 고려한 경우, 적응변조방식과 Truncated Type-II Hybrid ARQ 방식을 고려한 경우와 적응변조방식에 Truncated Type-II Hybrid ARQ 방식과 최대비합성 다이버시티 합성기법을 동시에 고려한 경우를 비교 분석한다.

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Improvement Performance of Truncated Type-II Hybrid ARQ Scheme and MRC Diversity Techniques using an Adaptive Modulation in DS -CDMA Cellular Mobile Communication System (DS-CDMA 셀룰라 이동통신 시스템에서 적응변조방식을 이용한 Truncated Type-II Hybrid ARQ 방식과 최대비 합성 다이버시티 기법에 의한 성능 개선)

  • 양재훈;김지웅;강희조
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.5 no.4
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    • pp.661-667
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    • 2001
  • This paper proposes a Truncated Type-II Hybrid ARQ scheme using an adaptive modulation system to achieve high throughput data transmission systems for DS-CDMA cellular mobile communication systems. In this paper, the adaptive modulation system analyzed in Nakagami (m-distribution) fading channel environment. The adaptive modulation system controls the modulation level and symbol rate according to the Nakagami fading parameter( m). When the received Eb/No is high or the Nakagami fading parameter m is high, the propose system selects higher modulation level and higher symbol rate to increase throughput. On the other hand, this system selects lower modulation level and lower symbol rate to prevent throughput performance degradation when the received Eb/No is low. The modulation method have been adopted QPSK 16QAM, 64QAM, 256QAM. Therefore, adaptive modulation systems with Truncated Type II Hybrid ARQ Scheme is proper for mobile and radio data communication system that require high reliability and delay-limited applications.

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Performance Analysis of Adaptive Modulation Systems with Truncated Type-II Hybrid ARQ Scheme and MRC Diversity Techniques in Nakagami Fading Environment (나카가미 페이딩 환경에서 Truncated Type-II Hybrid ARQ 방식과 최대비 합성 다이버시티 기법에 의한 적응변조방식의 성능 분석)

  • 양재훈;강희조
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.12 no.5
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    • pp.810-816
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    • 2001
  • This paper proposes a Truncated Type-II Hybrid ARQ scheme using an adaptive modulation system to achieve high throughput data transmission systems for mobile communication systems. In this paper, the adaptive modulation system analyzed in Nakagami (m-distribution) fading channel environment. The adaptive modulation system controls the modulation level and symbol rate according to the Nakagami fading parameter(m). When the received $E_bN_0$ is high or the Nakagami fading parameter m is high, the propose system selects higher modulation level and higher symbol rate to increase throughput. On the other hand, this system selects lower modulation level and lower symbol rate to prevent throughput performance degradation when the received $E_bN_0$ is low. The modulation method have been adopted QPSK(Quadrature Phase Shift Keying), 16 QAM(Quadrature Amplitude Modulation), 64 QAM, 256 QAM. Therefore, Adaptive Modulation Systems with Truncated Type-II Hybrid ARQ Scheme is proper for mobile and radio for mobile and radio data communication system that require high reliability and delay-limited applications.

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Performance Analysis of GFSK Systems by Impulsive Electromagnetic Noise in Indoor Radio Fading Channel Environment (실내 무선 페이딩 채널 환경에서 임펄스성 전자간섭파에 의한 GFSK시스템의 성능 분석)

  • 이양선;김지웅;강희조
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.12 no.7
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    • pp.1115-1121
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    • 2001
  • In this paper, we analyzed the performance of GFSK system that presence fading effect in indoor radio communication environments and impulsive electromagnetic noise from electronic equipments then we applied the Truncated Type- II Hybrid ARQ scheme to make satisfied in data transmission service. As a result, the system was influenced by fading and impulsive electromagnetic noise. Especially, the system was much degraded by high occurrence frequency and amplitude of impulsive electromagnetic noise than fading which has direct frequency. By adopting the Truncated Type-II hybrid ARQ technique we can also obtained the performance improvement in the low signal power(20 dB) arid over 24 dB in strong impulsive electromagnetic noise environment which is occurred error floor and terribly influenced by the system.

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Performance Improvement of Adaptive Modulation Systems in Wireless Multimedia Communication Environment (무선 멀티미디어 통신 환경에서 적응변조시스템의 성능개선)

  • 강희조
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.7 no.5
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    • pp.893-898
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    • 2003
  • This paper proposes a Truncated Type-II Hybrid ARQ scheme and coding techniques using an adaptive modulation system to achieve high throughput data transmission systems for wireless multimedia communication systems. In this paper, the adaptive modulation system analyzed in Nakagami (m-distribution) fading channel environment. The adaptive modulation system controls the modulation level and symbol rate according to the Nakagami fading parameter(m). When the received Eb/No is high or the Nakagami fading parameter m is high, the propose system selects higher modulation level and higher symbol rate to increase throughput. On the other hand, this system selects lower modulation level and lower symbol rate to prevent throughput performance degradation when the received Eb/No is low. The modulation method have been adopted QPSK(Quadrature Phase Shift Keying), 16QAM(Quadrature Amplitude Modulation), 64QAM, 256QAM. Therefore, adaptive modulation systems with truncated type-II hybrid ARQ scheme is proper for wireless multimedia communication system that require high reliability and delay-limited applications.

A Study on the QoS Improvement of Impulse Radio UWB System in Multiple Interference Environment (다중 간섭 환경에서 Impulse Radio UWB 시스템의 전송품질 향상에 관한 연구)

  • Jang, Se-In;Lee, Yang-Sun;Kim, Si-Gwan
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.14 no.11
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    • pp.2457-2462
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    • 2010
  • In this paper, We applied CCI canceller to remove multiple access interference in co-channel environment and improved performance of Impulse Radio UWB system. Also, we have evaluated the performance of UWB system with Truncated Type-II Hybrid ARQ scheme for achieving high quality data transmission.

A Study on the Performance Improvement of UWB System with Variable Bit-Rate in Imperfect Channel Environment (불완전 채널 환경에서 가변 전송율을 갖는 초광대역 전송시스템의 성능개선에 관한 연구)

  • Lee Yang-Sun;Kang Heau-Jo
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.9 no.7
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    • pp.1473-1478
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    • 2005
  • In this paper, we proposed UWB system with variable rate in piconet environment that several wireless devices moves as variable. And, we analyzed the performance of UWB system according to multiple access interference and transmission rate. Also, we have evaluated the performance of m system with Truncated Type-II Hybrid ARQ scheme fer achieving high qualify data transmission.

Optimum Technique for WATM Error Control in Indoor Environment (실내환경에서의 WATM 최적화 기법 연구)

  • Kang, Young-Heung;Shin, Song-Sup
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.4 no.5
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    • pp.1027-1035
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    • 2000
  • In this paper, we have proposed the optimum technique for wireless ATM (WATM) error control in indoor environment. As the optimum technique, the conventional concatenated FEC only is regarded as the efficient error control method for time-critical ATM traffic in AWGN, and the pilot symbol-added fading compensation with the concatenated FEC is required to optimize the WATM performance in fading environment. Also, the truncated Type- H hybrid ARQ technique will be developed for quality-critical ATM traffic in order to improve its throughput. Therefore, this paper presents the optimization of WATM performance in indoor environment by means of evaluating above techniques using theoretical analysis and simulation.

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Performance Analysis of FH/CDMA Systems with Impulse and Nakagami fading Radio Communication Channel (나카가미 페이딩과 임펄스 무선 통신로 채널에서 FH/CDMA 시스템의 성능분석)

  • 나기현;이양선;강희조
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2001.05a
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    • pp.727-731
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    • 2001
  • 된 논문에서는 임펄스 잡음과 다중접속간섭(MUI) 및 나카가미 페이딩 환경으로 모델링되는 FH/CDMA 시스템을 제안하고 이의 성능을 분석하였다. 결과에 의하면 FH-CDMA 시스템은 잡음이나 페이딩의 영향보다는 여러명의 사용자가 같은 시간에 같은 주파수를 사용함으로 인한 충돌과 임펄스 잡음에 의해 더 큰 영향을 받는다. 성능 개선기법으로 다이버시티 기법과 에러정정 부호화 기법을 사용함으로써 페이딩과 다중접속 간섭에 대하여 어느 정도의 개선효과를 보이지만 임펄스 잡음의 영향으로 무선 데이터 통신을 만족하는 시스템 성능을 가질수 없었다. 따라서 한번의 재전송만을 고려한 Truncated Type-II Hybrid ARQ기법을 동시에 채용함으로써 다중접속 간섭과 임펄스 잡음에 의한 전송에러를 감소시키고 고신뢰도의 무선 데이터 통신을 만족하는 시스템 성능을 보임을 알 수 있었다.

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