• Title/Summary/Keyword: Nakagami Channel

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Tight Bounds and Invertible Average Error Probability Expressions over Composite Fading Channels

  • Wang, Qian;Lin, Hai;Kam, Pooi-Yuen
    • Journal of Communications and Networks
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    • v.18 no.2
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    • pp.182-189
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    • 2016
  • The focus in this paper is on obtaining tight, simple algebraic-form bounds and invertible expressions for the average symbol error probability (ASEP) of M-ary phase shift keying (MPSK) in a class of composite fading channels. We employ the mixture gamma (MG) distribution to approximate the signal-to-noise ratio (SNR) distributions of fading models, which include Nakagami-m, Generalized-K ($K_G$), and Nakagami-lognormal fading as specific examples. Our approach involves using the tight upper and lower bounds that we recently derived on the Gaussian Q-function, which can easily be averaged over the general MG distribution. First, algebraic-form upper bounds are derived on the ASEP of MPSK for M > 2, based on the union upper bound on the symbol error probability (SEP) of MPSK in additive white Gaussian noise (AWGN) given by a single Gaussian Q-function. By comparison with the exact ASEP results obtained by numerical integration, we show that these upper bounds are extremely tight for all SNR values of practical interest. These bounds can be employed as accurate approximations that are invertible for high SNR. For the special case of binary phase shift keying (BPSK) (M = 2), where the exact SEP in the AWGN channel is given as one Gaussian Q-function, upper and lower bounds on the exact ASEP are obtained. The bounds can be made arbitrarily tight by adjusting the parameters in our Gaussian bounds. The average of the upper and lower bounds gives a very accurate approximation of the exact ASEP. Moreover, the arbitrarily accurate approximations for all three of the fading models we consider become invertible for reasonably high SNR.

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 of Block Error Probabilities of FS MC-CDMA System using BCH Coding Scheme in Slow Multipath Fading Channels (슬로우 다중경로 페이딩 채널환경에서 BCH 부호화기법을 이용한 FS MC-CDMA 시스템의 블록에러확률의 성능 개선)

  • Jin, Ze-Guang;Kang, Heau-Jo
    • Journal of Advanced Navigation Technology
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    • v.12 no.2
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    • pp.115-121
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    • 2008
  • In this paper, we analysis the error performance improvement of the FS MC-CDMA, whose information data are spread spectrum with direct sequences(DS), and each subband signal is transmitted using a subcarrier frequency, combining BCH code in Mobile communication channels which is characterized by Nakagami fading. The effect of co-channel interference on the block error performance is also studied in this paper. As a results of study, the coding techniques provides more efficient improvement than non-coding, but the coding techniques are required more band as many coding rate. Our study demonstrates that the system is combined coding techniques, the amount of improvement is capable of efficiently exploiting over the Nakagami fading.

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Performance Analysis of NOMA-based Relaying Networks with Transceiver Hardware Impairments

  • Deng, Chao;Zhao, Xiaoya;Zhang, Di;Li, Xingwang;Li, Jingjing;Cavalcante, Charles Casimiro
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.12 no.9
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    • pp.4295-4316
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    • 2018
  • In this paper, the performance of non-orthogonal multiple access (NOMA) dual-hop (DH) amplify-and-forward (AF) relaying networks is investigated, where Nakagami-m fading channel is considered. In order to cover more details, in our analysis, the transceiver hardware impairments at source, relay and destination nodes are comprehensively considered. To characterize the effects of hardware impairments brought in NOMA DH AF relaying networks, the analytical closed-form expressions for the exact outage probability and approximate ergodic sum rate are derived. In addition, the asymptotic analysis of the outage probability and ergodic sum rate at high signal-to-noise ratio (SNR) regime are carried out in order to further reveal the insights of the parameters for hardware impairments on the network performance. Simulation results indicate the performance of asymptotic ergodic sum rate are limited by levels of distortion noise.

Performance Analysis of MFSK-MDPSK/DS-CDMa System Employing Diversity Techniquies and Error Coding Technique in Nakagami Fading Environment (나카가미 페이딩 환경하에서 다이버시티기법과 에러 정정부호화 기법을 채용한 MFSK-MDPSK/DS-CDMA 시스템의 성능 분석)

  • 양원일;강희조
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.11 no.4
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    • pp.553-564
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    • 2000
  • In this thesis, mobile communication channel with multi-path fading which is major factor of performance degradation of DS-CDMA system has been considered. An MRC diversity and error correcting coding technique have been used to improve performance of MFSK-MDPSK/DS-CDMA system. The MFSK-MDPSK/DS-CDMA system performance has been obtained quantitatively by the numerical analysis. the modulations under consideration are noncoherent M-ary frequency shift keying(MFSK) and an MFSK based joint frequency phase modulation utilizing MFSK/DS-CDMA and MDPSK-DS-CDMA systems the MFSK-MDPSK/DS-CDMA system obtain a better performance . Also, the error performance of MFSK-MDPSK/DS-CDMA system in Nakagami fading environments is improved by increasing the number of diversity branch and coding gain.

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Exact Performance Analysis of AF Based Hybrid Satellite-Terrestrial Relay Network with Co-Channel Interference

  • Javed, Umer;He, Di;Liu, Peilin
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.9 no.9
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    • pp.3412-3431
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    • 2015
  • This paper considers the effect of co-channel interference on hybrid satellite-terrestrial relay network. In particular, we investigate the problem of amplify-and-forward (AF) relaying in hybrid satellite-terrestrial link, where the relay is interfered by multiple co-channel interferers. The direct link between satellite and terrestrial destination is not available due to masking by surroundings. The destination node can only receive signals from satellite with the assistance of a relay node situated at ground. The satellite-relay link is assumed to follow the shadowed Rice fading, while the channels of interferer-relay and relay-destination links experience Nakagami-m fading. For the considered AF relaying scheme, we first derive the analytical expression for the moment generating function (MGF) of the output signal-to-interference-plus-noise ratio (SINR). Then, we use the obtained MGF to derive the average symbol error rate (SER) of the considered scenario for M-ary phase shift keying (M-PSK) constellation under these generalized fading channels.

Differencing Multiuser Detection Using Error Feedback Filter for MIMO DS-UWB System in Nakagami Fading Channel

  • Kong, Zhengmin;Fang, Yanjun;Zhang, Yuxuan;Peng, Shixin;Zhu, Guangxi
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.6 no.10
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    • pp.2601-2619
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    • 2012
  • A differencing multiuser detection (MUD) method is proposed for multiple-input multiple-output (MIMO) direct sequence (DS) ultra-wideband (UWB) system to cope with the multiple access interference (MAI) and the computational efficiency in Nakagami fading channel. The method, which combines a multiuser-interference-cancellation-based decision feedback equalizer using error feedback filter (MIC DFE-EFF), a coefficient optimization algorithm (COA) and a differencing algorithm (DA), is termed as MIC DFE-EFF (COA) with DA for short. In the paper, the proposed MUD method is illuminated from the rudimental MIC DFE-EFF to the advanced MIC DFE-EFF (COA) with DA step by step. Firstly, the MIC DFE-EFF system performance is analyzed by minimum mean square error criterion. Secondly, the COA is investigated for optimization of each filter coefficient. Finally, the DA is introduced to reduce the computational complexity while sacrificing little performance. Simulations show a significant performance gain can be achieved by using the MIC DFE-EFF (COA) with DA detector. The proposed MIC DFE-EFF (COA) with DA improves both bit error rate performance and computational efficiency relative to DFE, DFE-EFF, parallel interference cancellation (PIC), MIC DFE-EFF and MIC DFE-EFF with DA, though it sacrifices little system performance, compared with MIC DFE-EFF (COA) without DA.

Performance Analysis of DS/CDMA with Phase Error Using Hybrid SC/MRC Diversity (위상을 고려한 DS/CDMA 시스템에서 Hybrid SC/MRC 다이버시티 기법을 이용한 성능분석)

  • 김원섭;박진수
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.7 no.3
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    • pp.355-362
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    • 2003
  • In this paper, we analyzed the DS/CDMA System with Hybrid SC/MRC diversity, as a method to achieve a good performance by reducing the complexity of system, when PLL gain value was revised a phase gulf among branches to make perfect coherent receive signal. The channel is a multipath Nakagami-m fading channel, we consider user(K), processor gain(N), number of paths(Lp) in DS/CDMA system with hybrid SC/MRC diversity. We found that PLL gain values exist to make perfect coherent receive signal. We verified that DS/CDMA system with Hybrid SC/MRC diversity can improve performance when the proper PLL gain values is used in the system. As a result, we verified that the upper limit of PLL gain value is 5dB to make perfect coherent receive signal in the DS/CDMA system with hybrid SC/MRC diversity.

Performance Analysis of FH MC/DS CDMA Stystem with Multi-tone Jamming over Nakakgami Fading Channel (나카가미 페이딩 채널하에서 멀티톤 재밍을 고려한 FH MC/DS CDMA 시스템의 성능분석)

  • Kim, Sang-Wook;Kim, Joon-Bae;Jung, Keun-Yeol;Yang, Jung-Mo;Park, Jin-Soo
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • v.9 no.1
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    • pp.543-546
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    • 2005
  • In this paper, it was estimated the BER performance of the individual system type by applying the SFH type and the FFH type to the FH MC-DS CDMA system that combined the strong points of MC DS/CDMA and that of Frequency Hopping under the Nakagami fading channel with Multi-tone Jamming. An increase in the number of hoppings means that it can improve the BER performance by reducing the receiving burden of the FH MC DS/CDMA by achieving a frequency diversity effect. Therefore, I verified that the performances of the FH MC DS/CDMA system could be improved by increasing the number of hoppings.

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Rake-Based Cellular Radar Receiver Design for Moving Target Detection in Multipath Channel

  • Kim, Yeejung;Jeong, Myungdeuk;Han, Youngnam
    • ETRI Journal
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    • v.36 no.5
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    • pp.799-807
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    • 2014
  • In this paper, we design a rake-based cellular radar receiver (CRR) scheme to detect a moving target located in a multipath environment. The modules of Doppler filter banks, threshold level test, and target detection module are newly introduced into the conventional rake receiver so that it can function as a radar system. The proposed CRR tests the Doppler-shift frequency and signal-to-noise ratio of the received signal against predefined threshold levels to determine detection and then calculates target velocities and ranges. The system performance is evaluated in terms of detection probability and the maximum detection range under a Nakagami-n channel that reflects the multipath environment.