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Chaos-coded modulations over Rician and Rayleigh flat fading channels

IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS II-EXPRESS BRIEFS 2008年第6期55卷 581-585页

作者： Escribano, Francisco J. Lopez, L. Sanjuan, M. A. F. Univ Rey Juan Carlos Dept Fis Mostoles 28933 Spain Univ Rey Juan Carlos Deartmento Sistemas Telemat & Computac Mostoles 28933 Spain

In this brief, we analyze a kind of chaos-coded modulations over both Rician and Rayleigh frequency non-selective uncorrelated fading in the presence of additive white Gaussian noise. We provide bounds both for the case when perfect channel-state information (CSI) is available at the decoder and when there is no CSI. We show that the bounds proposed can be tight enough to give reason of the behavior of these systems in a flat fading channel. We compare the results with a related trellis-coded modulation and show that the degradation in performance can be at least as low as with conventional coded modulation systems.

关键词： chaos error analysis fading channels modulation coding

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New concatenated coding and space-time modulation scheme for MIMO wireless communications

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IET COMMUNICATIONS 2007年第6期1卷 1111-1117页

作者： Wu, Z. Wang, X. Zhang, R. Concordia Univ Dept Elect & Comp Engn Montreal PQ H3G 1M8 Canada

Zheng and Tse have demonstrated that there exists an optimal trade-off between diversity gain and multiplexing gain. To realise the predicted optimal trade-off, we propose a new multiple-input multiple-output transmission scheme for a concatenated coding and space-time (ST) modulation system aimed at applications that require flexible trade-off between performance and data rate. The proposed scheme is multi-layered with linear ST modulation to allow various multiplexing gain. Through a judicious design of the inner ST modulation, the optimisation of spatial multiplexing is made simple. Moreover, a joint iterative receiver based on MMSE criterion with a priori information is developed to reduce computational complexity. Simulation results are provided to demonstrate the merits of the new design.

关键词： diversity reception iterative methods diversity gain multiplexing gain space-time codes MIMO wireless communications optimisation mean square error methods concatenated coding space-time modulation scheme MMSE criterion concatenated codes multiple-input multiple-output transmission scheme modulation coding multiplexing joint iterative receiver MIMO communication spatial multiplexing optimisation

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Adaptive coding and modulation for the DVB-S2 standard interactive applications: Capacity assessment and key system issues

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IEEE WIRELESS COMMUNICATIONS 2007年第4期14卷 61-69页

作者： Alberty, Eric Defever, Sophie Moreau, Cyrille De Gaudenzi, Riccardo Ginesi, Alberto Rinaldo, Rita Gallinaro, Gennaro Vernucci, A. EADS Astrium Toulouse France European Space Agcy ESTEC RF Payload & Syst Div NL-2200 AG Noordwijk Netherlands Space Engn SpA Rome Italy

Point-to-point multibeam satellite systems based on the DVB-S standard [1] are currently designed for link closure in the worst-case propagation and location conditions. The DVB-S standard, conceived for broadcasting applications, considers a fixed coding rate and modulation format that are selected according to the assumed coverage and availability requirements. This approach implies the occurrence of high margins in the majority of the cases, when interference and propagation conditions allow for higher signal-to-noise-plus-interference ratio. The adaptive coding and modulation (ACM) introduction in the new DVB-S2 standard [2] for the interactive service profile opens up a number of appealing opportunities for the design and development of satellite broadband networks. In this article we show how the ACM introduction in the,satellite downlink enables greatly enhanced system performance but also has a profound impact on the way the system and some of the key system components are designed.

关键词： Adaptive coding modulation coding Digital video broadcasting Physical layer Satellite broadcasting Downlink Attenuation Satellite antennas Interference Bit rate

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Hierarchical subgroup power and modulation coding adaptation - a new frequency-space link adaptation scheme in MIMO-OFDM eigenmode adaptive transmission system

Hierarchical subgroup power and modulation coding adaptation...

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IEEE Conference on Vehicular Technology (VTC)

作者： Le Hai Doan SeeHo Ting K. Sakaguchi K. Araki Graduate School of Information Science and Engineering Tokyo Institute of Technology Japan Graduate School of Science and Engineering Tokyo Institute of Technology Meguro Tokyo Japan

The MIMO-OFDM eigenmode adaptive transmission system (EMATS) is considered as one of the candidates for future high speed wireless communication networks. The system performance is evaluated for frequency-space domain power and modulation coding adaptation schemes on the MIMO-OFDM EMATS based on IEEE 802.11a, and a throughput of about 400 Mbps at SNR of 40 dB is achieved. Furthermore, we propose a hierarchical subgroup adaptation (HSA) algorithm which can drastically reduce the amount of overhead signaling and computational complexity with minimal performance loss. The efficiency of the proposed algorithm is validated by computer simulation under the condition of IEEE 802.11n channel models.

关键词： modulation coding Frequency Adaptive systems Computational complexity Wireless communication Computer simulation Receiving antennas Transmitting antennas MIMO System performance

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Introduction to the special issue on the IEEE 2007 Custom Integrated Circuits Conference

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IEEE JOURNAL OF SOLID-STATE CIRCUITS 2008年第8期43卷 1714-1716页

作者： Clark, Lawrence T. Gharpurey, Ranjt Heydar, Payam Arizona State Univ Dept Elect Engn Tempe AZ 85287 USA Univ Texas Austin Dept Elect & Comp Engn Austin TX 78712 USA Univ Calif Irvine Dept Elect & Comp Engn Irvine CA 92697 USA

This special issue of the IEEE Journal of Solid-State Circuits is a selection of papers published in the IEEE 2007 Custom Integrated Circuits Conference (CICC). The issue consists of 14 papers that cover a wide range of technical areas, including wireless and RF circuit design, mixed-signal and analog design, digital IC design, integrated power regulation, memory design and biological applications of IC technology. The selected papers demonstrate state-of-the-art performance in power, area, or integration along with innovative circuit implementations and techniques.

关键词： Special issues and sections Application specific integrated circuits CMOS technology modulation coding Radiofrequency integrated circuits Clocks Delta modulation Digital modulation Radio frequency Analog integrated circuits

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A side information based packet loss recovery algorithm in VoIP

A side information based packet loss recovery algorithm in V...

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1st International Congress on Image and Signal Processing

作者： Li, Zhongbo Zhao, Shenghui Wang, Jing Kuang, Jingming Beijing Inst Technol Dept Elect Engn Beijing 100081 Peoples R China

ISBN: (纸本)9780769531199

In VoIP (Voice over Internet Protocol) applications, packet loss affects the received speech quality greatly. PCM (Pulse Code modulation) coders are often used for VoIP and also face such problems. In this paper a side information based packet loss recovery algorithm is proposed, which introduces a small part of corrective information to provide an enhanced reconstruction of the lost packets. A virtual reconstruction is implemented for every original packet with side information and the redundancy is obtained with MMSE criterion at the sender endpoint. When packet loss happens, the lost packets will be recovered with side information and redundancy at the receiver endpoint. The simulation results show that the speech quality over IP network is obviously improved at the price of only a low bandwidth consumption with the proposed method.

关键词： Phase change materials Signal processing algorithms Internet telephony Image reconstruction Bandwidth Pulse modulation Protocols Redundancy Speech processing modulation coding

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Investigation of multilevel coded modulation in the application of the adaptive OFDM system

Investigation of multilevel coded modulation in the applicat...

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International Conference on Microwave and Millimeter Wave Technology

作者： Zhou Li Bian Guang-Feng Gu Ping Nanchang Hangkong Univ Sch Elect Informat Nanchang 330063 Jiangxi Peoples R China Guangxi Univ Sch Comp & Elect & Informat Nanchang 330063 Jiangxi Peoples R China

ISBN: (纸本)9781424418794

In this paper, a multilevel coded modulation scheme in adaptive OFDM system is presented. Set partitioning-based on the Asymmetric constellation has been used in this scheme to meet unequal error protection. The combination between multilevel coded modulation and adaptive technique can greatly improve the performance of the system. Simulation results have demonstrated the good performance of this proposed scheme which an intended bit error rate can be assured and the different quality of service can be met in data transmission.

关键词： OFDM modulation adaptive modulation error statistics modulation coding quality of service adaptive OFDM system bit error rate data transmission multilevel coded modulation partitioning-based on asymmetric constellation unequal error pr

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Effects of Intersymbol Interference on Chaos-Based modulations

Effects of Intersymbol Interference on Chaos-Based Modulatio...

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2nd International Conference on Signals, Circuits and Systems

作者： Escribano, Francisco J. Lopez, Luis Sanjuan, M. A. F. Univ Alcala Henares Dept Teoria Senal & Comunicac Alcala De Henares 28805 Spain Univ Rey Juan Carlos Dept Sistemas Telemat & Comp E-28933 Mostoles Spain Univ Rey Juan Carlos Dept Fis E-28933 Mostoles Spain

ISBN: (纸本)9781424426270

The behavior of chaos coded modulations (CCM's) in the field of digital communications has been mainly evaluated in additive white Gaussian noise (AWGN) and multipath fading channels. We study here some examples of CCM's over channels with time-invariant intersymbol interference (ISI). We provide bounds for low ISI levels and we show that these chaos-based coded systems can offer reasonable degree of robustness compared with similar coded modulation systems. We provide the analytical condition a CCM has to comply to stand a limited quantity of ISI. Our results are straightforwardly applicable to chaos-based systems of the same kind and provide a hint of the potentialities of CCM systems over dispersive channels.

关键词： Chaos Intersymbol interference modulation coding Error analysis

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The Anti-jamming Performance of GNSS BOC signals in Certain Jamming Environments

The Anti-jamming Performance of GNSS BOC signals in Certain ...

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8th International Symposium on Antennas, Propagation and EM Theory

作者： Chen Jun Zhang You-guang Liang Gao-bo Li fei Beijing Univ Aeronaut & Astronaut Beijing 100083 Peoples R China PLA Unit 63880 Luoyang Henan 4710034 Peoples R China

ISBN: (纸本)9781424421923

The Binary Offset Carrier planned for future GNSS signals, including several GALILEO signals as well as the GPS M-code, presents a high degree of spectral separation from conventional signals and improves positioning accuracy and enhances multipath rejection greatly. This paper discusses the characteristics of GNSS BOC signals, analyzes the anti-jamming performance of various GNSS BOC signals in Certain Jamming Environments, analyses the differences performance of various BOC signals in certain jamming environments, such as narrow interference, matching frequency spectrum interference and limited band white noise jamming.

关键词： Satellite navigation systems Jamming Global Positioning System Frequency modulation coding Signal analysis Performance analysis Bandwidth Interference Phase modulation

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Mutual information based rate adaptation for MIMO-OFDM systems with finite signal alphabets

Mutual information based rate adaptation for MIMO-OFDM syste...

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ITG Workshop on Smart Antennas

作者： Carsten Bockelmann Dirk Wubben Karl-Dirk Kammeyer Department of Communications Engineering University of Brethemen Germany

We consider a single user MIMO-OFDM system where spatial multiplexing is applied and formulate rate allocation algorithms to adapt the used modulation alphabet on a per subcarrier basis. As a means to consider the system behavior including the channel code regarding bit or frame error rate (BER, FER) versus normalized average mutual information (NAMI) of an OFDM symbol for several M-QAM alphabets is investigated. To this end an approximation to the mutual information of MIMO systems with M-QAM signal alphabets is derived and compared to channel decomposition approaches to find a complexity/accuracy trade-off. Based on the mutual information results two algorithms using this channel knowledge are introduced. On the one hand, the error rates can be optimized assuming a fixed rate requirement and on the other hand the achieved transmission rate can be optimized under a BER/FER constraint. In both cases a NAMI threshold derived from the simulated system behavior for a specific channel code is used to adapt the allocated modulation alphabets via a greedy algorithm to achieve the target NAMI within an error margin.

关键词： Mutual information Bit error rate Error analysis MIMO Constraint optimization Parity check codes OFDM modulation modulation coding Greedy algorithms Frequency conversion

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