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Transformation methods, coding and equalization for time- and frequency-selective channels

EUROPEAN TRANSACTIONS ON TELECOMMUNICATIONS 2000年第6期11卷 555-565页

作者： Reinhardt, M Egle, J Lindner, J Siemens AG D-89081 Ulm Germany Univ Ulm Dept Informat Technol D-89081 Ulm Germany

A method to generate transmit signal sets is proposed which are especially suited for transmission over Rayleigh fading channels. It is shown that this method in combination with a suitable iterative receive algorithm allows the asymptotical transformation of a Rayleigh channel into a set of parallel additive white gaussian noise (AWGN) subchannels. Therefore, coding methods designed for the AWGN channel are now applicable also to Rayleigh channels resulting in a coding gain that is separable into the known AWGN coding gain and an additional diversity gain attributable to the orthonormal transform. Starting from this result, the method is extended to a transmission over frequency and/or time-selective channels. This leads to an extension of the recently introduced multicarrier code division multiplexing (MC-CDM) scheme. A unified transmission model is derived which allows the application of the iterative reception algorithm also in the latter case and to transform time- and frequency-selective channels under certain assumptions asymptotically into a set of parallel AWGN subchannels. The performance of these transformation methods for an uncoded scheme and together with high rate trellis codes designed for the AWGN channel is investigated and compared to the matched filter bound (MFB). For the calculation of the MFB for channels with a separable time-variant transfer function a method is introduced that significantly reduces the complexity of computation.

关键词： Raleigh fading channels transmission Separable multifunction buffer AWGN channels coding coding gain selective channel AWGN Equalization subchannel

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INTERLEAVED CONVOLUTIONAL coding FOR THE TURBULENT ATMOSPHERIC OPTICAL COMMUNICATION CHANNEL

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IEEE TRANSACTIONS ON COMMUNICATIONS 1988年第9期36卷 993-1003页

作者： DAVIDSON, FM KOH, YT Department of Electrical and Computer Engineering The Johns Hopkins University Baltimore MD USA

The coding gain of a constraint-length-three, rate one-half convolutional code over a long clear-air atmospheric direct-detection optical communication channel using binary pulse-position modulation signalling is directly measured as a function of interleaving delay for both hard- and soft-decision Viterbi decoding. Maximum coding gains theoretically possible for this code with perfect interleaving and physically unrealizable perfect-measurement decoding were about 7 dB under conditions of weak clear-air turbulence, and 11 dB at moderate turbulence levels. The time scale of the fading (memory) of the channel was directly measured to be tens to hundreds of milliseconds, depending on turbulence levels. Interleaving delays of 5 ms between transmission of the first and second channel bits output by the encoder yield coding gains within 1.5 dB of theoretical limits with soft-decision Viterbi decoding. coding gains of 4-5 dB were observed with only 100 mu s of interleaving delay. Soft-decision Viterbi decoding always yielded 1-2 dB more coding gain than hard-decision Viterbi decoding.

关键词： attenuation memory decibel coding gain Viterbi decoding Optical communication Turbulent Flow convolutional coding soft decision dubnium MILLISECOND

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Near-Capacity Three-Stage Turbo Detection of Irregular Convolutional Coded Joint Sphere-Packing Modulation and Space-Time coding

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IEEE TRANSACTIONS ON COMMUNICATIONS 2009年第5期57卷 1486-1495页

作者： Alamri, O. Wang, J. Ng, S. X. Yang, L. -L. Hanzo, L. Univ Southampton Sch ECS Southampton SO9 5NH Hants England

Conventional two-stage turbo-detected schemes typically suffer from a Bit Error Rate (BER) floor, preventing them from achieving infinitesimally low BER values, especially, when the inner coding stage is of non-recursive nature. We circumvent this deficiency by proposing a three-stage turbo-detected Sphere Packing (SP) aided Space-Time Block coding (STBC) STBC-SP scheme, where a rate-1 recursive inner precoder is employed to avoid having a BER floor. The convergence behaviour of this serially concatenated scheme is investigated with the aid of 3D Extrinsic Information Transfer (EXIT) Charts. Furthermore, the capacity of the STBC-SP scheme is determined and an algorithm is proposed for calculating a tighter upper bound on the maximum achievable bandwidth efficiency, based on the EXIT charts of the STBC-SP demapper. The proposed three-stage turbo-detected scheme operates within about 1.0 dB of the capacity and within 0.5 dB of the maximum achievable bandwidth efficiency limit.

关键词： Channel capacity turbo detection three-stage concatenated codes sphere-packing modulation irregular codes space-time coding irregular convolutional codes iterative detection coding gain EXIT charts three-dimensional EXIT charts STBC code design

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Co-ordinate Interleaved Distributed Space-Time coding for Two-Antenna-Relays Networks

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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2009年第4期8卷 1783-1791页

作者： Harshan, J. Rajan, B. Sundar Indian Inst Sci Dept Elect Commun Engn Bangalore 560012 Karnataka India

Distributed space time coding for wireless relay networks when the source, the destination and the relays have multiple antennas have been studied by Jing and Hassibi. In this set-up, the transmit and the receive signals at different antennas of the same relay are processed and designed independently, even though the antennas are colocated. In this paper, a wireless relay network with single antenna at the source and the destination and two antennas at each of the R relays is considered. A new class of distributed space time block codes called Co-ordinate Interleaved Distributed Space-Time Codes (CIDSTC) are introduced where, in the first phase, the source transmits a T-length complex vector to all the relays;and in the second phase, at each relay, the in-phase and quadrature component vectors of the received complex vectors at the two antennas are interleaved and processed before forwarding them to the destination. Compared to the scheme proposed by Jing-Hassibi, for T >= 4R, while providing the same asymptotic diversity order of 2R, CIDSTC scheme is shown to provide asymptotic coding gain with the cost of negligible increase in the processing complexity at the relays. However, for moderate and large values of P, CIDSTC scheme is shown to provide more diversity than that of the scheme proposed by Jing-Hassibi. CIDSTCs are shown to be fully diverse provided the information symbols take value from an appropriate multidimensional signal set.

关键词： Cooperative communication distributed space-time coding co-ordinate interleaving coding gain

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CHANNEL coding WITH QUADRATURE QUADRATURE PHASE SHIFT-KEYING (Q2PSK) SIGNALS

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IEEE TRANSACTIONS ON COMMUNICATIONS 1990年第4期38卷 409-417页

作者： SAHA, D Department of Electrical Engineering and Computer Science George Washington University Washington D.C. DC USA

Channel coding due to trellis modulation has been proved to be useful for bandlimited channels. However, these modulations, mostly designed with n-use of 2D signals, are primarily aimed at coding gain only. It is pointed out that utilization of all available signal dimensions, which is limited by the time-bandwidth product, may improve the bandwidth efficiency and simultaneously bring an additional coding gain. Trellis coding with a spectrally efficient 4D signal set based on Q/sup 2/PSK is addressed. Without any expansion of the Q/sup 2/PSK signal set, a simple hand-designed 16-state trellis code provides a coding gain of 6.02 dB. With the same number of states in G. Ungergoeck\'s (1982) 8-PSK trellis, the gain is 4.1 dB. In low intersymbol interference situations, the bandwidth efficiency of this coded Q/sup 2/PSK is twice that of coded 8-PSK; if both operate at 2 b/s Hz and P/sub b/(E)=10/sup -5/, the coded Q/sup 2/PSK provides a saving of about 4 dB over the coded 8-PSK. Some fully connected trellises with an expanded signal due to 2-use of Q/sup 2/PSK signals are also presented. Two such codes ar rate-7/8 achieve a gain of 5.45 dB with only eight states.

关键词： decibel 8-PSK Phase shift Trellis codes numerical invariant Channel coding coding gain signals gain bandwidth efficiency dubnium

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Precoder Design for Amplify and Forward Relaying With Complex Field Network coding

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IEEE TRANSACTIONS ON SIGNAL PROCESSING 2011年第6期59卷 2988-2994页

作者： Ding, Yanwu Kwon, Hyuck M. Lee, Kanghee Wichita State Univ Dept Elect Engn & Comp Sci Wichita KS 67260 USA

In this correspondence, multiuser relay systems with amplify and forward relaying protocol are considered. To make transmission delays as short as possible, the concept of complex field network coding is applied. The relays transmit for all users simultaneously instead of using conventional relaying transmissions over orthogonal channels such as time-division multiplexing for each user. Three transmission schemes with two or three time-slot delays and symbol rates 1/2, 2/3, and 1 are examined. Based on the derived pairwise error probability expressions, optimal precoders achieving the maximum diversity and best coding gains are designed without changing the original ergodic capacity regions. Simulation results are provided to verify the proposed designs.

关键词： Amplify-and-forward coding gain diversity gain pairwise error probability throughput

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Modulation and coding for linear Gaussian channels

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IEEE TRANSACTIONS ON INFORMATION THEORY 1998年第6期44卷 2384-2415页

作者： Forney, GD Ungerboeck, G Motorola Inc Informat Syst Grp Mansfield MA 02048 USA IBM Corp Div Res Zurich Res Lab CH-8803 Ruschlikon Switzerland

Shannon's determination of the capacity of the linear Gaussian channel has posed a magnificent challenge to succeeding generations of researchers. This paper surveys how this challenge has been met during the past half century. Orthogonal minimum-bandwidth modulation techniques and channel capacity are discussed Binary coding techniques for lo low-signal-to-noise ratio (SNR) channels and nonbinary coding techniques for high-SNR channels are reviewed. Recent developments, which now allow capacity to be approached on any linear Gaussian channel, are surveyed. These new capacity-approaching techniques include turbo coding and decoding, multilevel coding, and combined coding/precoding for intersymbol-interference channels.

关键词： binary coding block codes canonical channel capacity coding gain convolutional codes lattice codes multicarrier modulation nonbinary coding orthogonal modulation precoding shaping gain single-carrier modulation trellis codes

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Theoretical Investigation of First-order and Second-order Polarization-mode Dispersion Tolerance on Various Modulation Formats in 40 Gb/s Transmission Systems with FEC coding

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JOURNAL OF THE OPTICAL SOCIETY OF KOREA 2009年第2期13卷 227-233页

作者： Jang, Hodeok Kim, Kyoungsoo Lee, Jaehoon Jeong, Jichai Korea Univ Dept Radio Engn Seoul 136701 South Korea

We investigated the polarization-mode, dispersion (PAID) tolerance for 40Gb/s non-return to zero (NEZ), duobinary NRZ, return to zero (RZ), carrier-suppressed RZ (CS-RZ), and duobinary-carrier-suppressed RZ (DCS-RZ) inoculation formats with a forward error correction (FEC) coding. The power penalty has been calculated as a measure of the system performance due to PMD. After comparison of the PAID tolerance of various modulation formats, our results suggest that, RZ signals have the best tolerance against the effect of first-order PMD only. The duobinary NRZ modulation format is most, resilient to PMD when both first- and second-order PMD are considered. However, the duobinary NRZ modulation format is the most sensitive to the incident angle of the input signal to a fiber axis in the presence of first- and second-order PMD, leading to incident angle-dependent;power penalty. The coding gain by FEC call cope with the power penalties induced by first- and second-order PMD up to a DGD value of 16ps.

关键词： Polarization mode dispersion Tolerance Forward error correction coding gain

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INTEGER COSINE TRANSFORMS FOR HIGH-EFFICIENCY IMAGE AND VIDEO coding

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CYBERNETICS AND SYSTEMS ANALYSIS 2016年第5期52卷 802-816页

作者： Hnativ, L. O. Natl Acad Sci Ukraine VM Glushkov Inst Cybernet Kiev Ukraine

Matrix methods for constructing one-norm order-8 and -16 integer cosine transforms are considered. One-norm order-8 and -16 integer transforms are proposed and fast algorithms are developed that implement these transforms with a low computational complexity that is less by a factor of 3-5 than the complexity of well-known algorithms and is less by a factor of 10 than that in the H.265 standard.

关键词： discrete cosine transform integer cosine transform factorization fast transform scaled transform coding gain compression ratio computational complexity video coding H.264 H.265 HEVC AVS

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A Method to Construct a Large-Size Simple Integer Cosine Transform for High-Resolution Image and Video coding

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CYBERNETICS AND SYSTEMS ANALYSIS 2016年第6期52卷 956-966页

作者： Hnativ, L. O. Natl Acad Sci Ukraine VM Glushkov Inst Cybernet Kiev Ukraine

A matrix method is considered to construct simple order-32 integer cosine step transform. A one-norm simple order-32 integer transform is proposed and its fast algorithms are developed whose computational complexity i... 详细信息

关键词： discrete cosine transform integer cosine transform integer cosine step transform scaled transform factorization fast transform coding gain compression ratio video coding H.264 H.265 AVS

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