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A NEW METHOD FOR THE INTEGRATION OF modulation AND CHANNEL coding IN AN ARQ PROTOCOL

IEEE TRANSACTIONS ON COMMUNICATIONS 1992年第10期40卷 1594-1606页

作者： BENELLI, G Dipartimento di Ingegneria Elettronica Universite di Pavia Pavia Italy

The combination of modulation and channel coding can improve the performance of a communication system. In this paper, a new method for the integration of the modulation operation in an automatic-repeat-request scheme is described. This method uses a memory for the successive transmissions of a codeword and, through a suitable encoding operation, the Euclidean distances among the codewords are significantly increased with the number of transmissions. The application of the described method to some different modulation schemes, as M-ary PSK with M > 2 and continuous-phase frequency shift keying modulation, is described. The optimum combination of the modulation and channel coding operations for some short block codes is also presented. The results of the theoretical analysis show that the method described in this paper permits improving both the error probability and the throughput of an ARQ protocol with respect to other similar schemes.

关键词： modulation coding Channel coding Automatic repeat request Phase shift keying Frequency shift keying Frequency modulation Block codes Error probability Throughput Protocols

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A modulation coding scheme for multi-channel PRML

A modulation coding scheme for multi-channel PRML

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IEEE International Symposium on Information Theory

作者： T. Guzeloglu J.G. Proakis Northeastern University Boston MA USA

A modulation coding scheme is described for multi-channel partial-response systems with maximum likelihood sequence detection. A linear equalization scheme is considered for interchannel interference problem.

关键词： modulation coding Decoding Interference Maximum likelihood detection Vectors AWGN Communication channels Magnetic heads Magnetic recording Viterbi algorithm

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PARTIAL RESPONSE CONTINUOUS PHASE modulation AND DPCM coding FOR SPEECH TRANSMISSION IN CELLULAR MOBILE RADIO SYSTEMS

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IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY 1986年第3期35卷 100-105页

作者： VARMA, VK GUPTA, SC SO METHODIST UNIV SCH ENGN & APPL SCI DEPT ELECT ENGN DALLAS TX 75275 USA

The performance of a speech transmission scheme with application to cellular digital mobile radio systems is considered. The source coder is embedded differential pulse code modulation (DPCM) and the modulation schemes belong to the class of partial response continuous phase modulation (CPM). Both quantizing noise and transmission errors contribute to the overall mean square error. The performance measure is the audio signal-to-noise ratio (SNR). It is seen that in a fading environment space diversity is very effective in bringing down the threshold of channel SNR to maintain the required audio SNR. The number of channels the system can support is evaluated under various conditions.

关键词： Continuous phase modulation Speech coding Land mobile radio Fading Pulse modulation Signal to noise ratio Receivers modulation coding Bandwidth Amplitude modulation

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modulation network coding

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IET COMMUNICATIONS 2013年第16期7卷 1715-1728页

作者： Ndih, Eugene David Ngangue Cherkaoui, Soumaya Univ Sherbrooke Dept Elect & Comp Engn Sherbrooke PQ J1K 2R1 Canada

In this study, we propose a four-dimensional modulation, referred to as modulation network coding (MNC), to address the problem of decoding a signal from multiple source node transmissions in mobile fast fading channels. The MNC scheme judiciously mixes a two-dimensional (2D) pilot symbol with a 2D information symbol, and makes use of a /4 rotated M-pulse-amplitude modulation (PAM) constellation to guaranty an effective decoding of all the interfering symbols even in the case of a smaller channel Doppler spread compared with the period of the MNC symbol. In addition, because the MNC scheme makes use of an additional dimension introduced through orthogonal pulse waveform, the use of the pilot symbols does not reduce the effective information rate. The analytical and simulation results show that it is possible to achieve a low symbol error probability with a good signal-to-noise ratio when controlling a few parameters impacting the performance of the system such as the synchronisation in time and in frequency of the source nodes.

关键词： decoding error statistics fading channels mobile radio modulation coding pulse amplitude modulation network coding modulation network coding four-dimensional modulation MNC scheme decoding multiple source node transmissions mobile fast fading channels two-dimensional pilot symbol 2D information symbol iEuro-4 rotated M-PAM constellation interfering symbols channel Doppler spread frequency synchronisation time synchronisation signal-to-noise ratio low symbol error probability information rate orthogonal pulse waveform

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modulation AND coding FOR SATELLITE AND SPACE COMMUNICATIONS

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PROCEEDINGS OF THE IEEE 1990年第7期78卷 1250-1266页

作者： YUEN, JH SIMON, MK MILLER, W POLLARA, F RYAN, CR DIVSALAR, D MORAKIS, J NASA GODDARD SPACE FLIGHT CTRAEROSP DATA STAND OFFGREENBELTMD 20771 MOTOROLA INC DIV STRATEG ELECTRCHANDLERAZ 85248

Several modulation and coding advances supported by NASA are summarized. To support long-constraint-length convolutional code, a VLSI maximum-likelihood decoder, utilizing parallel processing techniques, which is being developed to decode convolutional codes of constraint length 15 and a code rate as low as 1/6 is discussed. A VLSI high-speed 8-b Reed-Solomon decoder which is being developed for advanced tracking and data relay satellite (ATDRS) applications is discussed. A 300-Mb/s modem with continuous phase modulation (CPM) and codings which is being developed for ATDRS is discussed. Trellis-coded modulation (TCM) techniques are discussed for satellite-based mobile communication applications.< >

关键词： modulation coding Artificial satellites Maximum likelihood decoding Convolutional codes Very large scale integration NASA Parallel processing Reed-Solomon codes Relays Modems

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Slow and fast adaptive modulation and coding for uplink massive MIMO systems with packet retransmission

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IET COMMUNICATIONS 2022年第9期16卷 915-928页

作者： Radbord, Amin Harsini, Jalil S. Univ Guilan Dept Elect Engn POB *** Rasht Iran

Here, the authors consider the uplink of a cellular massive multiple-input multiple-output (MIMO) system with maximum ratio combiner (MRC) at base stations (BSs). To achieve a better QoS provisioning, users in the cells employ link adaptation using adaptive modulation and coding (AMC) in conjunction with packet retransmission. The authors present a cross-layer approach for the AMC design exploiting the time variation feature of MIMO wireless channels. At first, a fast AMC (FAMC) scheme is proposed to adapt the fast small-scale fading of the wireless channel based on the instantaneous channel state information. Since the fast fading is asymptotically averaged out due to the channel hardening property of massive MIMO system, we then suggest a slow AMC (SAMC) scheme which adjusts the adaptation parameters based on only the large-scale channel fading statistics including shadow fading and pass loss of the channel. The SAMC substantially reduces the feedback rate and implementation cost because of using a larger coherence time compared to that of the FAMC. For the proposed schemes, the probability density function of signal-to-interference-plus-noise ratio (SINR) for MRC receivers at BSs is analytically derived and verified by simulation. Also, closed-form expressions are presented for the throughput and packet error outage of the system. Index Terms-Massive MIMO, MRC, AMC, ARQ, Performance analysis.

关键词： adaptive modulation MRC receivers fading channels cellular massive MIMO system MRC adaptive modulation and coding probability density function MIMO wireless channels maximum ratio combiner modulation coding packet error outage MIMO communication telecommunication network reliability AMC design signal-to-interference-plus-noise ratio diversity reception cellular radio radiofrequency interference cellular massive multiple-input multiple-output system quality of service FAMC scheme probability QoS packet retransmission uplink massive MIMO systems

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Advanced channels for DVD with d=2 modulation coding

Advanced channels for DVD with d=2 modulation coding

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Optical Data Storage

作者： S. Gopalaswamy R. Wood Data Storage Institute NUS Singapore Singapore Storage Systems Division IBM San Jose CA USA Electrical and Computer Engineering NUS Singapore Singapore

modulation codes with d>0 are essential in optical recording to enable useful densities, since the minimum mark size achievable is limited by the diffraction-limited spot size. The EFMPLus modulation code is a coding scheme adopted for the digital video disk (DVD). This is a run-length limited code with constraints d=2 and k=10. It is appropriate to exploit this knowledge of the coding scheme in the detection strategies, to sustain high performance at higher densities and data rates. This paper presents the performance of two simple equalizers, one of which uses decision feedback, to achieve a target response that enables optimal detection by simple thresholding. The evaluations are done using a channel model. Equalization strategies that exploit the d=2 RLL constraint in the DVD channel provide improved performance of about 2 to 4 db for the DVD specifications.

关键词： DVD modulation coding Decision feedback equalizers Finite impulse response filter Electron optics Optical feedback Optical filters Optical recording Optical saturation Optical sensors

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COMBINED modulation AND coding FOR CONTINUOUS-PHASE FSK WITH NONUNIFORM ALPHABET

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IEEE TRANSACTIONS ON COMMUNICATIONS 1993年第8期41卷 1201-1207页

作者： LUISE, M REGGIANNINI, R Dipartimento di ingegneria dell'Informazione Universitá di Pisa Pisa Italy

This paper addresses the problem of combined coding and modulation for continuous-phase M-ary frequency-shift keyed (CPFSK) signals with a redundant symbol alphabet. It is shown that in many cases of interest, the use of a nonuniform mapping between coded bits and phase increments at the CPFSK modulator allows for a significant increase of free Euclidean distance in the coder/modulator state trellis as compared to the uniform alphabet case. A systematic search for optimum encoder/mapper/modulator structures is carried out for short constraint length rate 1/2 and 2/3 codes combined with 4-ary and 8-ary CPFSK, respectively, and for a relevant set of rational modulation indexes. Finally, the power-bandwidth efficiency of the optimum schemes is discussed and compared with that exhibited by the best coder/modulator structures previously proposed in the literature.

关键词： modulation coding Frequency shift keying Phase modulation Bandwidth Euclidean distance Maximum likelihood detection Continuous phase modulation Gaussian noise Viterbi algorithm Encoding

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CONCATENATED COMBINED modulation AND coding OF FREQUENCY HOPPING MULTIACCESS SYSTEMS

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IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS 1990年第4期8卷 650-662页

作者： RAHMAN, A ELHAKEEM, AK Department of Electrical and Computer Engineering Concordia University Montreal QUE Canada

A spread-spectrum system that does not have a separate state for initial code acquisition is presented. A uniform random variate selects one of several Gold codes for transmission, thus removing the notion of pseudorandom codes from spread-spectrum systems, making the effective code length infinite, and leading to acquisitionless systems. Because coding is critical to the proposed multiaccess frequency-hopping (FH) system, more powerful codes are needed. The performance of the proposed multiaccess system using the combined modulation and coding technique (trellis) concatenated with Reed-Solomon codes in partial-band jamming is investigated. The FH multiaccess performance of noncoherent soft detection of MFSK in association with trellis coding is introduced and the performance compared to that using RS outer/RS inner concatenated codes.< >

关键词： Concatenated codes modulation coding Frequency division multiaccess Multiaccess communication Gold Spread spectrum communication Demodulation Phase shift keying Reed-Solomon codes Jamming

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DISCRETE MULTIPLE TONE modulation WITH COSET coding FOR THE SPECTRALLY SHAPED CHANNEL

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IEEE TRANSACTIONS ON COMMUNICATIONS 1992年第6期40卷 1012-1029页

作者： RUIZ, A CIOFFI, JM KASTURIA, S INFORMAT SYST LAB DEPT ELECT ENGN STANFORD CA 94305 USA

In this paper we develop a discrete approach to multiple tone modulation for digital communication channels with arbitrary intersymbol interference (ISI) and additive Gaussian noise. Multiple tone modulation is achieved through the concatenation of a finite block length modulator based on discrete Fourier transform (DFT) code vectors, and well known high gain coset or trellis codes. Symbol blocks from an inverse DFT (IDFT) are cyclically extended to generate ISI-free channel-output symbols that decompose the channel into a group of orthogonal and independent parallel subchannels. The design of the energy distribution and coded information allocation over the subchannels is optimized for the finite block length case and for the coset code concatenation, leading to an implementable coding system with optimized performance for the channel with ISI. Asymptotic performance of this system is derived, and examples of asymptotic and finite block length coding gain performance for several channels is evaluated at different values of bits per sample. Using sufficiently long blocks for a particular ISI pattern, it can be shown that the implementable techniques presented here achieve the cut-off rate for any channel with ISI in the presence of additive Gaussian noise. In addition, this discrete multiple tone technique is linear in both the modulation and the demodulation, and is free from the effects of error propagation that often afflict systems employing bandwidth-optimized decision feedback plus coset codes.

关键词： modulation coding Discrete Fourier transforms Intersymbol interference Digital modulation Digital communication Additive noise Gaussian noise Convolutional codes Performance gain Demodulation

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