• Title/Summary/Keyword: Ungerboeck.

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Novel Trellis-Coded Spatial Modulation over Generalized Rician Fading Channels

  • Zhang, Peng;Yuan, Dongfeng;Zhang, Haixia
    • ETRI Journal
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    • v.34 no.6
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    • pp.900-910
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    • 2012
  • In this paper, a novel trellis-coded spatial modulation (TCSM) design method is presented and analyzed. Inspired by the key idea of trellis-coded modulation (TCM), the detailed analysis is firstly provided on the unequal error protection performance of spatial modulation constellation. Subsequently, the Ungerboeck set partitioning rule is proposed and applied to develop a general method to design the novel TCSM schemes. Different from the conventional TCSM approaches, the novel one based on the Ungerboeck set partitioning rule has similar properties as the classic TCM, which has simple but effective code design criteria. Moreover, the novel designed schemes are robust and adaptive to the generalized Rician fading channels, which outperform the traditional TCSM ones. For examples, the novel 4-, 8-, and 16-state TCSM schemes are constructed by employing different transmit antennas and different modulation schemes in different channel conditions. Simulation results clearly demonstrate the advantages of the novel TCSM schemes over the conventional ones.

Comprehensive Analysis of Turbo TCM over Two Typical Channels

  • Bai, Zhiquan;Yuan, Dongfeng;Kwak, Kyung-Sup
    • Journal of Communications and Networks
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    • v.9 no.1
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    • pp.11-17
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    • 2007
  • In this paper, system performance of turbo trellis coded modulation (turbo TCM) is presented and analyzed through computer simulations over two typical channels, namely additive white Gaussian noise (AWGN) and Rayleigh fading channels. We use and compare different mapping strategies based on Ungerboeck partitioning (UP), block partitioning (BP), mixed partitioning (MP), Gray partitioning (GP), and Ungerboeck-Gray partitioning (UGP) of the signal constellation of the turbo TCM system. Furthermore, taking 8PSK modulation of turbo TCM as an example, our simulation results show that turbo TCM with UP can obtain better performance than turbo TCM with BP, MP, GP, and UGP in both AWGN and Rayleigh fading channels.

Optimized Algebra LDPC Codes for Bandwidth Efficient Modulation

  • Hwang, Gi-Yean;Yu Yi;Lee, Moon-Ho
    • Journal of electromagnetic engineering and science
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    • v.4 no.1
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    • pp.17-22
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    • 2004
  • In this paper, we implement an efficient MLC/PDL system for AWGN channels. In terms of the tradeoff between the hardware implementation and system performance, proposed algebra LDPC codes are optimized by the Gaussian approximation(GA) according to the rate of each level assigned by the capacity rule and chosen as the component code. System performance with Ungerboeck Partitioning(UP), Miked Partitioning(MP) and Gray Mapping(GM) of 8PSK are evaluated, respectively. Many results are presented in this paper; they can indicate that the proposed MLC/PDL system using optimized algebra LDPC codes with different code rate, capacity rule and Gray mapping(GM) can achieve the best performance.

Radix-trellis Viterbi Decoding of TCM/PSK using Metric Quantization (TCM/PSK의 양지화 Radix-trellis Viterbi 복호)

    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.11 no.5
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    • pp.731-737
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    • 2000
  • In this paper we propose a decoding algorithm of Ungerboeck TCM/PSK in the concept of Radix-trellis, which has been applied to the decoding of convolutional codes for the high speed decoding. As an example we choose 16-state trellis coded 8-ary PSK. For Radix-4 and Radix-16 trellis decoding, we explain the path metric(PM) and the branch metric(BM) calculation. By using the simulation, we evaluate the bit error rate(BER) performance according to the number of binary digits for I-Q value, PM and BM registers. The proper number of binary digits of each register has been derived.

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A Study on Evaluation of MTCM with Optimum Encoder (최적부호기의 MTCM 성능 이득에 관한 연구)

  • 김민호;박재운;변건식
    • Journal of the Korea Society of Computer and Information
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    • v.4 no.4
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    • pp.185-192
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    • 1999
  • In this paper. for $\pi$/4 and $\pi$/8 PSK. we proposed to condition to obtain coding gain increasing states, by design encoder of analytical method with minimal complexity in limited bandwidth and power channels. In order to improve the bit error rate(BER), comparing Ungerboeck designed the TCM. we propose MTCM(Multiple trellis-coded modulation) with multiplicity(k=2), by optimum encoder design. By design encoder of analytical method. the trellis encoder can be minimal complexity and the decoder be used Viterbi decoder(MLSE). When compared to the TCM and MTCM with AWGN channels. the condition of performance enhancement of the MTCM with multiplicity(k=2) is the case of parallel transition in TCM systems. without alternating data transmission rate in bandwidth and power limited channels.

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A Study on the performance evaluation with TCM and MTCM in the mobile radio environment (이동 무선 환경에서의 TCM 및 MTCM의 성능 비교 평가)

  • 김민호
    • Journal of the Korea Society of Computer and Information
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    • v.5 no.4
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    • pp.90-95
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    • 2000
  • In order to enhance the confidence in the mobile communication and improve the performance of the bit error, we have been using coding method. In the case of this, we have to add redundancy bits by using error correcting codes such as the block or convolutional codes. However, the result of redundancy bits causes to improve confidence. but to drop the efficiency in the bandwidth. We have studied coding method that we are able to get the good coding gain without any changes in the data transmission rates in the limited bandwidth. In this Paper, we design TCM(Trellis Coded Modulation) which was proposed by Ungerboeck and MTCM(Multiple TCM), with multiplicity(k=2), which was proposed by Divsalar, using the optimum encoder. As state number is varied in the optimum encoder, we compare the performance of the TCM and MTCM by using Monte Carlo simulation.

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Analysis of a TC-16ADPSK Performance for Transmitting Different Information on One Channel Simultaneously (TC-16ADPSK을 사용한 이종 정보 동시 전송용 변조방식의 성능 분석)

  • 이원석;강희훈;이성백
    • Journal of the Institute of Electronics Engineers of Korea TE
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    • v.37 no.5
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    • pp.71-76
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    • 2000
  • A TC-16ADPSK scheme for transmitting different kinds of information simultaneously is proposed in this paper. The scheme is designed for simultaneously transmitting two kinds of Information on one channel. In signal mapping, a data of two kinds of information is used to phase modulation on Star-16APSK constellation and the other to amplitude modulation. In detection, each data independently recovers from mixing signal on each detector Therefore, we can transmit two kinds of Information on one channel can be transmitted efficiently. BER performance of the proposed scheme is analyzed on AWGN channel and Rayleigh fading channels on a computer with Matlab communication toolbox. On same SNR, the Gray code mapping has more 0.5-1.5dB coding gains than Ungerboeck's code mapping gains.

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