检索结果-内蒙古大学图书馆

Method of combining space-time block coding with adaptive beamforming

Journal of Southeast University(English Edition) 2005年第3期21卷 254-259页

作者：沈克勤解放军理工大学指挥自动化学院南京210007

A method of space-time block coding （STBC） system based on adaptive beamforming of cyclostationarity signal algorithm is *** method uses cyclostationarity of signals to achieve adaptive beamforming,then constructs a pair of low correlated transmit beams based on beamform estimation of multiple component signals of *** these two selected transmit beams,signals encoded by STBC are transmitted to achieve diversity gain and beamforming gain at the same time,and increase the signal to noise ratio （SNR） of *** simple computation and fast convergence performance,the proposed scheme is applicable for time division multiple access （TDMA） wireless communication operated in a complex interference *** results show that the proposed scheme has better performance than conventional STBC,and can obtain a gain of about 5 dB when the bit error ratio （BER） is 10-4.

关键词： space-time coding gain adaptive beamforming cyclostationary signal transmit diversity

来源：评论

学校读者我要写书评

暂无评论

Machine-Learning-Enabled Multi-Frequency Synthesis of space-time-coding Digital Metasurfaces

引用

ADVANCED FUNCTIONAL MATERIALS 2024年第40期34卷

作者： Rossi, Marco Zhang, Lei Chen, Xiao Qing Liu, Che Castaldi, Giuseppe Cui, Tie Jun Galdi, Vincenzo Univ Sannio Dept Engn Fields & Waves Lab I-82100 Benevento Italy Southeast Univ Inst Electromagnet Space Nanjing 210096 Peoples R China Southeast Univ State Key Lab Millimeter Waves Nanjing 210096 Peoples R China

Digital metasurfaces based on space-time coding have established themselves as a powerful and versatile platform for joint spatial/spectral control of electromagnetic waves. However, their advanced design remains a largely open problem with significant computational challenges. This study introduces a novel approach, based on deep neural networks, to address this challenge. The proposed technique enables the simultaneous and independent multi-frequency synthesis of scattering patterns, allowing precise tailoring of the harmonic equivalent currents (both in magnitude and phase), and enhancing spectral efficiency. These results, experimentally validated at X-band microwave frequencies, substantially broaden the capabilities of space-time coding digital metasurfaces, paving the way for advanced applications in wireless communications, sensing, and imaging. This study addresses the multi-frequency synthesis of space-time-coding digital metasurfaces via a machine-learning-based method that offers improved control over harmonic beam shaping/steering and increased spectral efficiency. Synthesized examples include Dolph-Chebyshev, Fourier-based, diffuse-scattering, and orbital-angular-momentum patterns. These outcomes, experimentally verified at X-band microwave frequencies, hold promise for applications to wireless communications, sensing, and imaging scenarios. image

关键词： digital metasurfaces machine learning reconfigurable intelligent surfaces smart radio environments space-time coding

来源：评论

学校读者我要写书评

暂无评论

Differential space-time network coding in MIMO two-way relay channel network

引用

INTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS 2016年第3期29卷 553-566页

作者： Jin, Xiaoping Han, Xinqiang Jin, Ning Li, Youming Li, Zhengquan Wang, Xiuming Ningbo Univ Inst Commun Technol Ningbo 315211 Zhejiang Peoples R China Southeast Univ Sch Informat Sci & Engn Nanjing 210096 Jiangsu Peoples R China China Jiliang Univ Dept Informat Engn Hangzhou 310018 Zhejiang Peoples R China

This paper focuses on noncoherent detection scheme for multiple-input multiple-output two-way relay channel network with two two-antennas source nodes and one single-antenna relay node. An orthogonal differential space-time network coding (ODSTNC) scheme based on relay detection and forward protocol is proposed. The proposed scheme combines space-time coding with network coding, and the differential modulation and detection are used in both multiple access stage and broadcast stage. The multiplesymbol differential detection is employed at the relay. The maximum likelihood decision and its low-complexity sphere decoding decision are given. The upper and lower bounds on the average symbol error probability for this system under differential binary phase shift keying (DBPSK) are derived, and a diversity order of 2 is confirmed to be achieved. The simulation results show that the ODSTNC scheme has good performance, and it is available for the applications of far distance signal transmission between two terminals where channel state information is unknown. Copyright (c) 2014 John Wiley & Sons, Ltd.

关键词： differential detection space-time coding network coding two-way relay channel network symbol error probability

来源：评论

学校读者我要写书评

暂无评论

Subband adaptive array for space-time block coding

引用

IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES 2006年第11期E89A卷 3103-3113页

作者： Bin Ramli, Nordin Tran, Xuan Nam Taniguchi, Tetsuki Karasawa, Yoshio Univ Electrocommun AWCC Chofu Tokyo 1828585 Japan Univ Electrocommun Dept Informat & Commun Engn Chofu Tokyo 1828585 Japan

Diversity transmission using space-time block coding (STBC) shows a degraded performance-in frequency selective fading (FSF) channel. In this paper, assuming the CSI is unknown at both transmitter and receiver while a pilot signal is available during the training period, we propose a MIMO transmission scheme using STBC by adopting subband adaptive array (SBAA) processing. The receive signal is converted into the frequency-domain and adaptive processing is done at each subband. A novel construction of SBAA is introduced to process received signal based on STBC. Simulation results demonstrate that the proposed scheme has a better performance compare to conventional STBC, and has a better performance and less computational load compare to STBC-TDLAA.

关键词： MIMO space-time coding subband adaptive array cyclic-prefix frequency selective fading channel

来源：评论

学校读者我要写书评

暂无评论

Power control scheme for multiple antenna systems with space-time coding in Rayleigh fading channels

引用

Journal of Systems Engineering and Electronics 2011年第5期000卷

作者： Xiangbin Yu1 2 and Guangguo Bi2 1.College of Electronic and Information Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 P.R.China 2.National Mobile Communications Laboratory Southeast University Nanjing 210096 P.R.China College of Electronic and Information Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016 P. R. China National Mobile Communications Laboratory Southeast University Nanjing 210096 P. R. China National Mobile Communications Laboratory Southeast University Nanjing 210096 P. R. China

Two optimal power control (PC) schemes under the power constraint for space-time coded multiple input multiple output systems over the flat Rayleigh fading channel with the imperfect channel state information (CSI) are *** is based on the minimization of a bit error rate (BER),and the other is based on the maximization of a fuzzy signal-to-noise *** these schemes,different powers are allocated to individual transmit antennas rather than equal power in the conventional *** the first scheme,the optimal PC procedure is *** is shown that the Lagrange multiplier for the constrained optimization in the power control does exist and is unique.A practical iterative algorithm based on Newton's method for finding the Lagrange multiplier is *** the second scheme,some existing schemes are included,and a suboptimal PC procedure is developed by means of the asymptotic performance *** this suboptimal scheme,a simple PC calculation formula is provided,and thus the calculation of the PC will be ***,the suboptimal scheme has the BER performance close to the optimal *** results show that the two PC schemes can provide BER lower than the equal PC and antenna selection scheme under the imperfect CSI.

关键词： power control (PC) space-time coding imperfect channel state information (CSI) bit error rate (BER) signal-tonoise ratio (SNR)

来源：评论

学校读者我要写书评

暂无评论

A LOW-COMPLEXITY ITERATIVE RECEIVER FOR MULTIUSER space-time BLOCK coding SYSTEMS

引用

International Journal on Wireless & Optical Communications 2007年第2期4卷 143-164页

作者： HA H. NGUYEN YAJUN YANG Department of Electrical & Computer Engineering University of Saskatchewan Saskatoon Canada S7N5A9 Canada

In an iterative receiver of a bandwidth-efficient multiuser space-time block coding (STBC) system, the extrinsic information is iteratively exchanged among the soft-input soft-output (SISO) channel decoders, the soft-output multiuser detector and the soft-output M-ary demodulators. Error performance, complexity and efficiency of the extrinsic information exchange are the most important properties of an iterative receiver. Taking these factors into account, sigma mapping is first applied to M-QAM constellations to yield a low-complexity soft-output minimum mean squared error (MMSE) demodulator to be used in the iterative receiver. Then a low-complexity two-loop iterative receiver is proposed for the multiuser STBC systems. It is shown that by running an additional inner iteration (between the channel decoders and the M-ary demodulators) for every outer iteration (between the channel decoders and the multiuser detector), the proposed receiver is superior to the conventional one, in which only one inner iteration is executed per one outer iteration. The results in this paper are therefore useful for wireless applications that employ space-time coding and require a very high bandwidth efficiency.

关键词： Multiuser system space-time coding interference cancellation joint detection and decoding sigma mapping EXIT chart

来源：评论

学校读者我要写书评

暂无评论

Near-Optimum Detection for Use in Closed-Loop Distributed space time coding with Asynchronous Transmission and Selection of Two Dual-Antenna Relays

Near-Optimum Detection for Use in Closed-Loop Distributed Sp...

引用

European Wireless 2013;19th European Wireless Conference

作者： Walid Qaja Abdulghani Elazreg Jonathon Chambers Advanced Signal Processing Group School of Electronic Electrical and Systems Engineering Loughborough University

We consider amplify-and-forward (AF) type cooperative wireless relay networks employing single bit closed-loop extended orthogonal space-time block coding (CL EO-STBC) over two selected cooperating relay nodes. Selection is performed from a set of NR available relay nodes each equipped with two antennas and outer convolutive coding is used to improve performance. A near-optimum detection scheme is used at the destination node for overcoming the effects of imperfect synchronization among selected relay nodes. End-to-end simulation results show that the employed detection scheme can effectively eliminate the interference components induced by asynchronism with low detection complexity. Furthermore, the one-bit feedback scheme and relay selection technique can enhance the overall system performance and outperform previous feedback methods.

关键词： relay optimum detection asynchronous transmission space-time coding Asynchronous System performance Trunk Node Simulation results Ganglia

来源：评论

学校读者我要写书评

暂无评论

Distributed space time coding for Wireless Two-way Relaying

Distributed Space Time Coding for Wireless Two-way Relaying

引用

IEEE Global Communications Conference

作者： Vijayvaradharaj T. Muralidharan B. Sundar Rajan Dept. of ECE IISc

ISBN: (纸本)9781467309202

We consider the wireless two-way relay channel, in which two-way data transfer takes place between the end nodes with the help of a relay. For the Denoise-And-Forward (DNF) protocol, it was shown by Koike-Akino et. al. that adaptively changing the network coding map used at the relay greatly reduces the impact of Multiple Access interference at the relay. The harmful effect of the deep channel fade conditions can be effectively mitigated by a proper choice of these network coding maps at the relay. Alternatively, in this paper we propose a Distributed space time coding (DSTC) scheme, which effectively removes most of the deep fade channel conditions at the transmitting nodes itself without any CSIT and without any need to adaptively change the network coding map used at the relay. It is shown that the deep fades occur when the channel fade coefficient vector falls in a finite number of vector subspaces of C2, which are referred to as the singular fade subspaces. DSTC design criterion referred to as the singularity minimization criterion under which the number of such vector subspaces is minimized is obtained. Also, a criterion to maximize the coding gain of the DSTC is obtained. Explicit low decoding complexity DSTC designs which satisfy the singularity minimization criterion and maximize the coding gain for QAM and PSK signal sets are provided. Simulation results show that at high Signal to Noise Ratio, the DSTC scheme provides large gains when compared to the conventional Exclusive-OR network code and performs slightly better than the adaptive network coding scheme proposed by Koike-Akino et. al.

关键词： high SNR relay coding gain space-time coding Network coding signal to noise ratios Bidirectional Subspace Multiple access interference network map

来源：评论

学校读者我要写书评

暂无评论

Distributed space time coding for Bit-Interleaved Coded Modulation in Two-Way Relaying Communications

Distributed Space Time Coding for Bit-Interleaved Coded Modu...

引用

IEEE Global Communications Conference

作者： Hongzhong Yan Ha H. Nguyen Department of Electrical and Computer Engineering University of Saskatchewan

ISBN: (纸本)9781479959532

This paper proposes a design of distributed space-time coding (DSTC) for the multiple access (MA) phase of a two-way relaying communication system. Bit-interleaved coded modulation (BICM) is used by the two terminal nodes and decoding based on the quaternary code representation is adopted at the relay. Based on an upper bound of the error probability, the impact of DSTC on the error performance is analyzed by considering three error types in the MA phase. Specifically, it is shown that type-3 errors need to be carefully taken into account in the design of a DSTC scheme. By developing a performance metric related to type-3 errors, a single parameter can be searched and its optimal value is obtained. To corroborate the analysis and optimization, simulation results are provided to show the advantage of the proposed DSTC scheme over other schemes under both Rayleigh and Rician fading channels.

关键词： Bit interleaved coded modulation space-time coding error performance relaying Rician fading channels Performance metrics Bidirectional Communication Research Error probability Best value Rayleigh DEcoding relay

来源：评论

学校读者我要写书评

暂无评论

Dynamic Buffer-aided Distributed space time coding Techniques for Cooperative DS-CDMA Systems

Dynamic Buffer-aided Distributed Space Time Coding Technique...

引用

WSA 2016;20th International ITG Workshop on Smart Antennas

作者： Jiaqi Gu Rodrigo C. de Lamare

In this work, we propose a dynamic buffer-aided distributed space-time coding (DSTC) scheme for cooperative direct-sequence code-division multiple access systems. We first devise a relay selection algorithm that can automatically select the optimum set of relays among both the source-relay phase and the relay-destination phase for DSTC transmission according to the signal-to-interference-plus-noise ratio (SINR) criterion. Multiple relays equipped with dynamic buffers are introduced in the network, which allows the relays to store data received from the sources and wait until the most appropriate time for transmission. The proposed technique improves the quality of the transmission with an acceptable delay as the buffer size is adjustable. Simulation results show that the proposed dynamic buffer-aided DSTC scheme and algorithm outperforms prior art.

关键词： Direct-sequence code-division multiple access relay space-time coding selection algorithm transmission quality CDMA mobile communications transmission

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：