检索结果-内蒙古大学图书馆

IEEE International Symposium on Antennas and Propagation / USNC/URSI National North American Radio Science Meeting

作者： Belaoura, Widad Ghanem, Khalida Djeddou, Mustapha EMP Commun Syst Lab Algiers Algeria CDTA Syst Architecture Lab Algiers Algeria

ISBN: (纸本)9781479978151

The presence of inter-symbol interference (ISI), in addition to multiple access interference (MAI), severely hampers the performance of a communication system. To overcome such impairments, the OFDM-CDMA and OFDM-IDMA techniques have been proposed. In this paper, the space-time block coding (STBC) scheme is used in the aforementioned OFDM-CDMA and OFDM-IDMA architectures with two transmit antennas, in order to offer an additional reliability of the wireless link. The performance gain over the SISO configuration is demonstrated.

关键词： transmitting antennas space time block coding multiple-input single-output ARCHITECTURE Multiple access interference intersymbolic interference Radio links GSTZ1 gene

来源：评论

学校读者我要写书评

暂无评论

Performance Enhancement of Cognitive Radio Spectrum Sharing (CRSS) with MIMO System

Performance Enhancement of Cognitive Radio Spectrum Sharing ...

引用

IEEE International Conference on Computer, Communication and Control (IC4)

作者： Kale, Pranil Sunil Lohiya, Padma DY Patil Coll Engn Pune Maharashtra India

ISBN: (纸本)9781479981632

A key challenge in operating cognitive radios (CRs) in a self-organizing (ad hoc) network is to adaptively and efficiently allocate transmission powers and spectrum among CRs according to the surrounding environment. Cognitive radio networks provide high bandwidth to mobile users via heterogeneous wireless architectures and dynamic spectrum access techniques. CR networks inflict challenges due to the fluctuating nature of the available spectrum, as well as the diverse QoS requirements of various applications. This paper considers a multiuser spectrum sharing (SS) system operating in a different fading environment and every node in the system is equipped with multiple antennas. The system employs orthogonal space-time block coding at the secondary users. The average capacity and error performance under a peak interference constraint are analyzed for this system using the distributed algorithm. For a comparison purpose, an analysis of the transmit antenna selection scheme is also presented.

关键词： Spectrum sharing cognitive radio multiuser diversity space time block coding

来源：评论

学校读者我要写书评

暂无评论

Performance Enhancement of Cognitive Radio Spectrum Sharing (CRSS) with MIMO System

Performance Enhancement of Cognitive Radio Spectrum Sharing ...

引用

International Conference on Computing, Communication and Security (ICCCS)

作者： Kale, Pranil Sunil Lohiya, Padma DY Patil Coll Engn Pune Maharashtra India

ISBN: (纸本)9781467393546

关键词： Spectrum sharing cognitive radio multiuser diversity space time block coding

来源：评论

学校读者我要写书评

暂无评论

A Pipelined Schnorr - Euchner Sphere Decoder Architecture for MIMO Systems

A Pipelined Schnorr - Euchner Sphere Decoder Architecture fo...

引用

International Conference on Advanced Technologies for communications (ATC)

作者： Xuan-Nghia Nguyen Minh-Tuan Le Ngoc-Nam Pham Vu-Duc Ngo Hanoi Univ Sci & Technol Hanoi Vietnam Ha Noi Dept Sci & Technol Hanoi Vietnam Mobifone Cooperat Hanoi Vietnam

ISBN: (纸本)9781467383745

The combination of multiple-input multiple-output (MIMO) and space-time block coding (STBC) is a potential solution for increasing throughput and reliability in data transmission. A pipelined architecture for a Schnorr-Euchner algorithm based sphere decoder used in STBC systems is proposed in this paper. The architecture was designed for a 2x2 antenna system with 16-quadrature amplitude modulation (16-QAM). The architecture was synthesized and implemented on a Xilinx Virtex-7 FPGA. The implementation results have shown that the proposed architecture outperforms existing ones in terms of throughput and maximum clock frequency thanks to pipelined processing.

关键词： multiple input multiple output systems space time block coding ARCHITECTURE Building construction decoders Throughput data transmission Spheres

来源：评论

学校读者我要写书评

暂无评论

RANDOMIZED space-time block coding FOR DISTRIBUTED AMPLIFY-AND-FORWARD COOPERATIVE RELAYS

RANDOMIZED SPACE-TIME BLOCK CODING FOR DISTRIBUTED AMPLIFY-A...

引用

IEEE International Conference on Acoustics, Speech, and Signal Processing

作者： Francesco Verde Anna Scaglione University Federico II Naples Italy University of California Davis CA USA

ISBN: (纸本)9781424442959

Cooperation diversity schemes employing space-time block coding (STBC) techniques have been proposed for wireless networks to increase network capacity and coverage even when each node is equipped with a single antenna. Such schemes allow several relay stations distributed in space to assist the transmission between a given source-destination pair. A key design problem in cooperative networks is to take advantage from spatial diversity by reducing the amount of signaling and processing overhead as far as possible. In this paper, capitalizing on randomized STBC (RSTBC), a coding method which has been recently developed for decode-and-forward (D&F) relay nodes, a totally decentralized cooperative communication scheme is proposed for amplify-and-forward (A&F) relays, where each relay is unaware of both the effective STBC being employed by the other nodes and the number of cooperating stations. Numerical results are provided to highlight the effectiveness of the proposed scheme in comparison to its D&F counterpart.

关键词： Amplify-and-forward relaying cooperative wireless networks relay design space-time randomized coding relay space time block coding Wireless networks Relay stations spacetime spatial diversity network capacity design problems DEUTERIUM FLUORIDES

来源：评论

学校读者我要写书评

暂无评论

Omnidirectional STBC Design in Massive MIMO Systems

Omnidirectional STBC Design in Massive MIMO Systems

引用

IEEE Global Communications Conference

作者： Xin Meng Xiang-Gen Xia Xiqi Gao National Mobile Communications Research Laboratory Southeast University Institute of Electronics Xidian University

ISBN: (纸本)9781479959532

Common signals in public channels of cellular systems should be transmitted omnidirectionally from the base station (BS) to ensure cell-wide coverage. In this paper, we propose two omnidirectional space-time block codes (STBCs), being referred to as precoded Alamouti code and precoded quasi-orthogonal STBC (QOSTBC), respectively, to provide omnidi-rectional signaling with spatial diversity for public channels in massive MIMO systems. Both of these two schemes are with low downlink pilot overhead and can guarantee omnidirectional transmission and equal-power transmission per antenna simul-taneously, to ensure reliable cell-wide coverage and sufficiently utilize all the available power amplifier capacities at BS antennas, respectively. The precoded Alamouti code provides diversity order 2 and has fast single-symbol maximum-likelihood (ML) decoding. The precoded QOSTBC provides a higher diversity order 4, but at the expense of a higher decoding complexity, since the ML decoding must be done on each pair of the modulation symbols.

关键词： Massive MIMO space-time block code (STBC) Alamouti code Quasi-orthogonal STBC (QOSTBC) Public channel Omnidirectional transmission Broadcast multiple input multiple output systems shared channel space time block coding broadcasting DEcoding spatial diversity cellular system

来源：评论

学校读者我要写书评

暂无评论

Irregular Multidimensional Constellations for Orthogonal STBCs

Irregular Multidimensional Constellations for Orthogonal STB...

引用

IEEE Global Communications Conference

作者： Hossein Khoshnevis Ian Marsland Halim Yanikomeroglu Department of Sytems and Computer Engineering Carleton University

ISBN: (纸本)9781479959532

Utilizing multiple antennas at the transmitter and receiver provides higher data rates and better reliability by exploiting spatial diversity. space-time block codes (STBCs) is a simple approach for using multiple transmit and receive antennas that has been widely employed in standards. The STBCs introduced in the literature use independent two-dimensional constellations, while the performance of orthogonal STBCs may be improved with multidimensional constellations. These constellations are transmitted by combining multiple space-time resources to form a multidimensional signal space. In this paper, we propose a method for finding optimized multidimensional constellations for orthogonal STBCs. Optimization is performed by minimizing a novel bound on the block or symbol error rate. We show that a substantial improvement in the error probability can be achieved with these novel constellations.

关键词： CONSTELLATIONS Error probability MULTIDIMENSIONAL signal space Orthogonal Bit error rate multiple antenna Data transfer rates simplicial approximation space time block coding

来源：评论

学校读者我要写书评

暂无评论

time-reversal space-time codes in asynchronous two-way double-antenna relay networks

Time-reversal space-time codes in asynchronous two-way doubl...

引用

IEEE International Conference on Acoustics, Speech and Signal Processing

作者： Y. Liu W. Zhang P. C. Ching Dept. of Electron. Eng. Chinese Univ. of Hong Kong Hong Kong China

ISBN: (纸本)9781467369985

We consider an asynchronous two-way relay network, in which two double-antenna relays assist in the communication between two single-antenna terminals through analog network coding. The asynchronous transmission between relays and terminals causes symbol misalignments and results in diversity loss in space-time block code (STBC). We propose a zero-padded time-reversal quasi-orthogonal STBC that can achieve full diversity with low-complexity maximum likelihood (ML) decoding, given a bounded delay. With ML decoding, the proposed code is decomposed into several independent parts, which leads to single complex symbol decoding. Proof of full diversity is established, and the decoding complexity order is analyzed for the proposed design. Simulations confirm the full diversity gain. The bit error rate performance in asynchronous scenarios is almost the same as that in synchronous scenarios.

关键词： Asynchronous analog network coding full diversity maximum likelihood decoding space-time code two-way relay network space-time codes Asynchronous Relay networks bit error rate performance maximum likelihood decoding analog network Bidirectional DEcoding relay Bidirectional Network space time block coding Computer Programming Languages

来源：评论

学校读者我要写书评

暂无评论

Simply decoded efficient full-rate space-time block codes over correlated Rician fading channels

引用

IET COMMUNICATIONS 2014年第10期8卷 1684-1695页

作者： Kuhestani, Ali PilAram, Hossein Mohammadi, Abbas Amirkabir Univ Technol Dept Elect Engn Tehran Iran Sharif Univ Technol Dept Elect Engn Tehran Iran

A novel technique is presented to design efficient full-rate space-time block codes (STBCs) over correlated Rician fading channels. The authors first derive a formula for the achievable information rate of a linear dispersion coded multi-input single-output system as a function of correlation at the transmitter in a Rician fading channel. In addition, the authors obtain the bit-error-rate (BER) equations for this system, when multiple phase shift keying and multiple quadrature amplitude modulation schemes are used at the transmitter. Therefore with regard to derived formulae and using a genetic algorithm, a method is presented to construct STBCs over correlated Rician fading channels. The efficient designed STBCs for two and four transmit antennas enjoy full-rate, simple structure, simple processing at the receiver, better BER performance than associated orthogonal STBCs at practical signal-to-noise ratios (SNRs) and higher achievable information rate than them at all SNRs.

关键词： bit error rate performance output system formula multiple phase shift keying space time block coding multilevel quadrature amplitude modulation Information rates block codes Rician fading channels Rician fading

来源：评论

学校读者我要写书评

暂无评论

Low PAPR and Spatial Diversity for OFDM Schemes by using L2-Orthogonal CPM ST-Codes with Fast Decoding 6

Low PAPR and Spatial Diversity for OFDM Schemes by using L2-...

引用

IEEE Latin-America Conference on Communications LATINCOM

作者： Hisojo, Miguel Angel Lebrun, Jerome Deneire, Luc Univ Nice Sophia Antipolis CNRS Lab I3S Nice France

ISBN: (纸本)9781479971626

Orthogonal Frequency Division Multiplexing (OFDM) is a popular modulation technique that provides high data rates and good robustness against frequency selective fading. space-time block coding (STBC) is an efficient way to introduce space-time diversity in Multiple-Input Multiple-Output (MIMO) systems. Using non-linear modulations such as Continuous Phase Modulation (CPM) with its constant envelope and continuous phase properties could be a solution to construct MIMO OFDM systems and to avoid the structural limitations of linear codes and alleviate the typical PAPR issue of OFDM. However, a major issue with CPM based systems may remain: the decoding complexity. In this paper, we introduce a new space-time-frequency diversity technique based on L2-orthogonal multi-h CPM space-time codes designed for OFDM transmission. We benchmark these codes under Rayleigh frequency selective channels and show how they achieve full spatial diversity at full rate for any number of antennas, good spectral compactness and also robustness to frequency fading. Furthermore, the decoding complexity is highly reduced and even made linear in the number of antennas thanks to the orthogonality properties.

关键词： MIMO communication OFDM modulation Rayleigh channels antenna arrays computational complexity decoding diversity reception linear codes space-time block codes CPM CPM-based systems L2-orthogonal CPM ST-codes L2-orthogonal multiA CPM space-time codes MIMO OFDM systems OFDM transmission PAPR issue Rayleigh frequency selective channels STBC constant envelope continuous phase modulation continuous phase properties decoding complexity fast decoding frequency selective fading full-spatial diversity modulation technique multiple-input multiple-output systems nonlinear modulation orthogonal frequency division multiplexing orthogonality properties space-time block coding space-time diversity space-time-frequency diversity technique spectral compactness Bit error rate Decoding Frequency diversity Modulation OFDM Transmitting antennas Orthogonal frequency division multiplexing space time block coding linear codes multiple input multiple output systems DEcoding Critical path method continuous phase modulation nonlinear modulation selective fading Frequency diversity transmitting antennas MIMO communication spatial diversity Raleigh fading channels diversity reception

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：