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IEEE International Symposium on Information Theory

作者： Victor Y. Krachkovsky Razmik Karabed Shaohua Yang Bruce A. Wilson Avago Technologies Allentown Pennsylvania USA Avago Technologies San-Jose California USA

We consider the problem of designing modulation codes for magnetic recording (MR) channels and other binary channels with ISI, where Markov sources are known to provide the best known lower bound on capacity. Our approach includes computing a costly channel matching a Markov source optimized for a given ISI channel. We then construct encoders and decoders for a modulation code matched to this costly channel.

关键词： Markov processes Vectors Encoding Decoding Entropy modulation coding

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MULTIMODE modulation AND coding OF QAM

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IEEE TRANSACTIONS ON COMMUNICATIONS 1993年第1期41卷 1-6页

作者： CHUNG, HY WILSON, SG UNIV VIRGINIA DEPT ELECT ENGNCHARLOTTESVILLEVA 22901

A general-purpose modulation and coding implementation is described based on the QAM family of modulation. The technique utilizes the ''superposed'' property of certain rectangular QAM constellations, along with the fact that optimal four-state trellis codes for such constellations are essentially identical, to provide a single modem architecture capable of performing over a wide range of power and bandwidth efficient transmission using either uncoded or coded modulation scheme. While the specific modulation and coding techniques are not new, we believe that their intrinsic compatibility is not well known and provides attractive system flexibility.

关键词： modulation coding Quadrature amplitude modulation Quadrature phase shift keying Convolutional codes Modems Constellation diagram Energy efficiency Bandwidth Digital communication Data communication

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THE MARITIME SATELLITE COMMUNICATION CHANNEL - CHANNEL MODEL, PERFORMANCE OF modulation AND coding

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IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS 1987年第4期5卷 701-713页

作者： HAGENAUER, J DOLAINSKY, F LUTZ, E PAPKE, W SCHWEIKERT, R DFVLR GERMAN AEROSP RES ESTABINST COMMUN TECHNOLDEPT DIGITAL NETWORKD-8031 OBERPFAFFENHOFENFED REP GER DFVLR GERMAN AEROSP RES ESTABINST COMMUN TECHNOLDEPT COMMUN SYSTD-8031 OBERPFAFFENHOFENFED REP GER

Towards the year 2000, maritime satellite communications using the INMARSAT system will employ a second and third generation of satellites and new ship earth stations (SES). The new SES standards will use very small antennas with gains between 0 and 15 dBi. At the lower end of SES there will be no antenna stabilization. The communication channel for such small stations is described by a model including multipath fading, Doppler shift, and noise. The results of an extensive measurement program were used to determine the parameters of the channel model, which depend on antenna type and elevation angle. Analytical calculations as well as synthetic and stored channel hardware simulations have been used to determine the performance of several modulation schemes. A complete data link using PSK modems with AFC/Costas loop, interleaving, and FEC codecs at 1.2 kbits/s was built up around a hardware maritime channel simulator, to study the performance of data transmission on the small SES maritime channel. Theoretical and measured results are given for interleaved Viterbi decoding with channel state information and Reed-Solomon codes. The measurements show that with interleaved FEC schemes, the required E_{b}/N_{o} for a BER 10 -5 is in the range of 9-15 dB and the effects of multipath fading are almost compensated for.

关键词： Satellite communication modulation coding Fading Hardware Artificial satellites Marine vehicles Satellite ground stations Communication channels Doppler shift Antenna measurements

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RESULTS ON CONTROLLED POLARITY modulation AND coding

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IEEE TRANSACTIONS ON MAGNETICS 1989年第5期25卷 4090-4092页

作者： WEATHERS, AD FRENCH, CA WOLF, JK UNIV IDAHO DEPT ELECT ENGNMOSCOWID 83843

The authors present results on a controlled-polarity modulation/coding scheme. They review this scheme and describe how to choose certain code parameters for the purpose of comparing the controlled polarity scheme to conventional (d,k) coding with NRZI modulation. A computer simulation is then utilized to compare the different schemes in terms of effective signal-to-noise ratio (SNR) and peak shift. It is shown that the controlled polarity schemes have less peak shift than the conventional schemes, whereas the conventional schemes have a higher effective SNR. It appears that in systems with a high enough SNR, the loss in effective SNR could be outweighed by the decrease in average peak shift. This could be of particular interest in future systems using magnetoresistive heads which have the potential to yield substantially higher SNRs.< >

关键词： modulation coding Magnetic recording Signal to noise ratio Pulse modulation Lifting equipment Magnetic modulators Computer simulation Pulse generation Passband Testing

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Moore state machine for adaptive modulation and coding in high-speed railway LTE-R systems

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ELECTRONICS LETTERS 2016年第9期52卷 776-777页

作者： Zhao, Yisheng Chen, Zhonghui Ji, Hong Fuzhou Univ Coll Phys & Informat Engn Fuzhou 350108 Peoples R China Beijing Univ Posts & Telecommun Minist Educ Key Lab Universal Wireless Commun Beijing 100876 Peoples R China

An adaptive modulation and coding (AMC) scheme based on a Moore state machine is proposed for the high-speed railway communication systems. By setting a buffer zone for the signal-to-noise ratio threshold value, the proposed scheme is able to reduce the frequent transition of the modulation and coding scheme. Simulation results show that the proposed AMC strategy has a more stable spectral efficiency than the traditional AMC method using a piecewise function.

关键词： Long Term Evolution adaptive codes railway communication signal processing modulation coding Moore state machine LTE-R systems adaptive modulation and coding high-speed railway communication systems buffer zone signal-to-noise ratio threshold value frequent transition AMC strategy AMC method piecewise function

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Channel coding for 4G systems with adaptive modulation and coding

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IEEE WIRELESS COMMUNICATIONS 2002年第2期9卷 8-13页

作者： Classon, B Blankenship, K Desai, V Motorola Labs Schaumburg IL USA

Future 4G mobile systems, whether evolutionary (e.g., evolutions of WCDMA and cdma2000) or based on technology such as OFDM applied to a wide-area environment, can achieve very large average user throughputs by using adaptive modulation and coding (AMC) instead of fixed modulation (e.g., QPSK) and power control. This article discusses the impact of the underlying channel coding in 4G systems with AMC. It is shown that 3G-style turbo coding can provide a 0.5-4 dB link gain over 256-state convolutional codes, depending on the frame size, modulation, and channel. The link gains from channel coding (or other techniques) do not directly translate into throughput gains for AMC, but can still be expected to improve throughput significantly. A method of generating soft information for higher order modulations based on reuse of the turbo decoding circuitry is also provided.

关键词： Adaptive systems Convolutional codes modulation coding OFDM modulation Throughput Turbo codes Iterative decoding Programmable control Adaptive control Interleaved codes

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Interval modulation coding

Interval modulation coding

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IEEE International Symposium on Information Theory

作者： S. Mukhtar J. Bruck California Institute of Technology Pasadena CA USA

We propose a new modulation scheme and a new architecture for the design of communication and storage systems. The modulation scheme is based on modulating pulse width and the architecture is based on time measurement... 详细信息

关键词： modulation coding Pulse width modulation Clocks Space vector pulse width modulation Decoding Time measurement Amplitude modulation Phase locked loops Pulse circuits Pulse measurements

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Queuing analysis for HCCA with adaptive modulation coding over wireless LANs

Queuing analysis for HCCA with adaptive modulation coding ov...

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International Conference on Communication Systems

作者： Reza Ghazizadeh Pingzhi Fan Institute of Mobile Communications Southwest Jiaotong University Chengdu China

In this paper, a queuing model is introduced to analyze the HCF controlled channel access (HCCA/IEEE802.11e) used in multi-rate wireless local area networks using adaptive modulation and coding, which is a key to wireless networks to increase effective transmission rate. The proposed model which is based on a MAP/PH/1 queue with vacation and time-limited service is useful in optimizing the parameters in cross layer designs and improving spectrum efficiency. Using Markovian arrival process (MAP) for traffic arrival process and phase type (PH) distribution for service process, vacation and non-transmission period make the mode more comprehensive to support practical traffic streams. To formulate the model, powerful matrix-geometric method is employed, and the mutual impacts of some parameters in the MAC and PHY layers are then evaluated and optimized to improve system performance.

关键词： Queueing analysis modulation coding Wireless LAN Traffic control Adaptive systems Programmable control Adaptive control Wireless networks Design optimization Cross layer design

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A joint adaptive subpacket size and modulation coding scheme with variable bandwidth

A joint adaptive subpacket size and modulation coding scheme...

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Global Mobile Congress

作者： Ke Pan Yong Zuo Xueyong Liu Jie Chen Communication and Multimedia SoC Laboratory Institute of Microelectronics Chinese Academy and Sciences Beijing China

ISBN: (纸本)9781424453023

In the wireless communication systems, the bandwidth is usually variable because of the dynamic channel. Although the optimal number of subpackets and AMC scheme has been proposed recently, it is limited to the fixed bandwidth. In this paper, a cross-layer design named AMC-SPS-SVB which combines AMC and ASPS with SR-ARQ is proposed to maximize the throughput of the system in a dynamic channel with the variable bandwidth. Curve fitting is applied here to give out approximate expressions of bit error rate under given modulation and coding schemes. General closed-form expressions of effective spectrum efficiency and optimal subpacket size under given modulation and coding schemes for our algorithm are presented. Furthermore, an efficient method is provided to find the optimal AMC and subpacket size. Numerical results show that the proposed algorithm improves the throughput of the system and works well with the variable bandwidth.

关键词： modulation coding Bandwidth Automatic repeat request Throughput Application specific processors Wireless communication Cross layer design Curve fitting Bit error rate Closed-form solution

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Joint design of modulation coding scheme for MIMO quasi-static fading systems

Joint design of modulation coding scheme for MIMO quasi-stat...

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IEEE Princeton Section Sarnoff Symposium

作者： Jialing Li I-Tai Lu Department of ECE Polytechnic Institute of New York University Brooklyn NY USA

ISBN: (纸本)9781424455928;9781424455935

A joint design of modulation coding scheme for MIMO quasi-static fading systems is developed to provide high data rate and to minimize frame error probability. The main design idea is, at first, to decompose the MIMO system into multiple parallel SISO systems using singular value decomposition. Secondly, the design metric is obtained from an upperbound of pairwise error probability of the equivalent SISO systems. Thirdly, the joint design is obtained by finding the best asymmetric constellation and labeling of constellation points for a given baseline trellis structure of each SISO system through an exhaustive search. Simulation shows our joint design gives consistant performance gain.

关键词： modulation coding MIMO Fading Upper bound Singular value decomposition Symmetric matrices Matrix decomposition Error probability Pairwise error probability Labeling

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