检索结果-内蒙古大学图书馆

A Robust Channel Estimator for High-Mobility STBC-OFDM Systems

IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS I-REGULAR PAPERS 2010年第4期57卷 925-936页

作者： Chen, Hsiao-Yun Ku, Meng-Lin Jou, Shyh-Jye Huang, Chia-Chi Natl Chiao Tung Univ Dept Elect Engn Hsinchu 300 Taiwan Natl Chiao Tung Univ Dept Commun Engn Hsinchu 300 Taiwan

In this paper, a robust channel estimator for high-mobility space-time block code-orthogonal frequency division multiplexing (STBC-OFDM) systems is proposed and applied in IEEE 802.16e systems. A high-performance two-stage channel estimation method is adopted. The proposed architecture reduces computational complexity effectively and improves 85.2% of the hardware implementation. The performances of the proposed design have been demonstrated through the simulation of an STBC-OFDM system with two transmit antennas and one receive antenna. At the vehicle speed of 120 and 240 km/hr for quadrature phase shift keying (QPSK) modulation, the proposed design can achieve the bit-error rate (BER) of about 10(-4) and 10(-3) without using channel coding. Moreover, it has significant performance improvement as compared with interpolation-based channel estimation methods. The proposed channel estimator implemented in 90 nm CMOS technology can support up to 29.03 Mbps (uncoded) downlink data transmission. The design only requires 859.6 K gates and dissipates 43.71 mW at 83.3 MHz operating frequency with 1 V power supply.

关键词： Channel estimator space-time block code orthogonal frequency division multiplexing IEEE 802.16e

来源：评论

学校读者我要写书评

暂无评论

Achieving space and time Diversity by Using Lattice Constellation Based Joint Alamouti Coding

引用

IEEE COMMUNICATIONS LETTERS 2010年第1期14卷 33-35页

作者： Liu, Wei Sellathurai, Mathini Tang, Chaojing Wei, Jibo Natl Univ Def Technol Sch Elect Sci & Engn Changsha 410073 Peoples R China Queens Univ Belfast Inst Elect Commun & Informat Technol Belfast BT3 9DT Antrim North Ireland

In this letter, we propose a simple space-time code to simultaneously achieve both the space and time diversities over time dispersive channels by using two-dimensional lattice constellations and Alamouti codes. The proposed scheme still reserves full space diversity and double-real-symbols joint maximum likelihood decoding which has the similar computation complexity as the Alamouti code.

关键词： Multi-input-multi-output space-time block code multi-dimensional lattice constellation time diversity space diversity

来源：评论

学校读者我要写书评

暂无评论

On Power Allocation for Alamouti STBC OFDM Systems with Distributed Transmit Antennas in the Presence of Residual Frequency Offsets

On Power Allocation for Alamouti STBC OFDM Systems with Dist...

引用

6th International Conference on Wireless Communications, Networking and Mobile Computing (WICOM)

作者： Sun, Ke Shao, Shihai Tang, Youxi Wang, Yi Zhang, Jiayin Univ Elect Sci & Technol China Natl Key Lab Sci & Technol Commun Chengdu 610054 Peoples R China Huawei Technol Co Ltd Corp Res Dept Shanghai Peoples R China

ISBN: (纸本)9781424437092

This paper proposes a transmit power allocation scheme for distributed transmit antenna Alamouti space-time block coded (STBC) orthogonal frequency division multiplexing (OFDM) systems using Cholesky decision-feedback detection in the presence of multiple residual frequency offsets (RFOs). Multipath Rayleigh fading is considered, and separate power constraint on each transmit antenna is assumed. The lower bound on the average bit error ratio (BER) performance is derived, and the optimal power allocation scheme based on minimizing that bound is then proposed. Simulation results show that the proposed power allocation scheme in certain cases only consumes as little as 50-65% of the transmit power used by the full power allocation scheme while enhancing the BER performance.

关键词： distributed transmit antennas space-time block code orthogonal frequency division multiplexing transmit power allocation residual frequency offsets

来源：评论

学校读者我要写书评

暂无评论

A Design of High-Rate Full-Diversity STBC with Low-Complexity PIC Group Decoding

A Design of High-Rate Full-Diversity STBC with Low-Complexit...

引用

IEEE Global Telecommunications Conference (GLOBECOM 2010)

作者： Shi, Long Zhang, Wei Xia, Xiang-Gen Univ New South Wales Sch Elect Engn & Telecommun Sydney NSW 2052 Australia Univ Delaware Dept Elect & Comp Engn Newark DE 19716 USA

ISBN: (纸本)9781424456383

In this paper, we propose a systematic design of space-time block codes (STBC) which can achieve high rate and full diversity when the partial interference cancellation (PIC) group decoding is used at receivers. The proposed codes can be applied to any number of transmit antennas and admit a low decoding complexity while achieving full diversity. For M transmit antennas, in each codeword real and imaginary parts of PM complex information symbols are parsed into P diagonal layers and then encoded, respectively. With PIC group decoding, it is shown that the decoding complexity can be reduced to a joint decoding of M/2 real symbols. In particular, for 4 transmit antennas, the code has real symbol pairwise (i.e., single complex symbol) decoding that achieves full diversity and the code rate is 4/3. Simulation results demonstrate that the full diversity is offered by the newly proposed STBC with the PIC group decoding.

关键词： decoding diversity reception high-rate full-diversity STBC interference suppression low-complexity PIC group decoding partial interference cancellation space-time block code space-time block codes transmitting antenna transmitting antennas

来源：评论

学校读者我要写书评

暂无评论

High-rate Complex Orthogonal space-time block codes for 5 and 6 Transmit Antennas

引用

WIRELESS PERSONAL COMMUNICATIONS 2009年第2期49卷 263-274页

作者： Xu, Changlong Gong, Yi Yang, Wei Nanyang Technol Univ Sch Elect & Elect Engn Singapore 639798 Singapore Southeast Univ Natl Mobile Communicat Res Lab Nanjing 210096 Peoples R China Nanyang Technol Univ Sch Elect & Elect Engn Singapore 639798 Singapore Beijing Jiaotong Univ State Key Lab Rail Traff Control & Safety Beijing 100044 Peoples R China Southeast Univ Natl Mobile Commun Res Lab Nanjing 210096 Peoples R China

Based on orthogonal designs, space-time (ST) block codes that enable full diversity as well as a simple maximum likelihood (ML) decoding algorithm at the decoder can be constructed for more than two transmit antennas. For real constellations (such as PAM), ST block codes with transmission rate 1 can be designed from the real Hurwitz-Radon families for any number of transmit antennas. However, for complex constellations (such as M-PSK or M-QAM), ST block codes for more than two transmit antennas can only be constructed with rates less than 1. Previous attempts have been concentrated on complex orthogonal designs that provide ST block codes with full diversity and high transmission rates. In this paper, we present two rate 2/3 complex ST block codes from orthogonal designs for five and six transmit antennas, respectively. Simulation results are provided to demonstrate the significant performance gains made by the proposed ST block codes.

关键词： space-time block code Orthogonal design Transmit diversity code rate

来源：评论

学校读者我要写书评

暂无评论

Some Designs and Normalized Diversity Product Upper Bounds for Lattice-Based Diagonal and Full-Rate space-time block codes

引用

IEEE TRANSACTIONS ON INFORMATION THEORY 2009年第2期55卷 569-583页

作者： Liao, Huiyong Wang, Haiquan Xia, Xiang-Gen Univ Delaware Dept Elect & Comp Engn Newark DE 19716 USA

In this paper, we first present two tight upper hounds for the normalized diversity products (or product distances) of 2 x 2 diagonal space-time block codes from quadratic extensions on Q(i) and Q(zeta(6)), where i = root-1 and zeta(6) = exp(i2 pi/6). Two such codes are shown to reach the tight upper bounds and therefore have the maximal normalized diversity products. We present two new diagonal space-time block codes from higher order algebraic extensions on Q(i) and Q(zeta(6)) for three and four transmit antennas. We also present a nontight upper bound for normalized diversity products of 2 x 2 diagonal space-time block codes with QAM information symbols, i.e., in Z[i], from general 2 x 2 complex-valued generating matrices. We then present an n x n-diagonal space-time code design method directly from 2n real integers based on extended complex lattices (of generating matrix size n x 2n) that are shown to have better normalized diversity products than the optimal diagonal cyclotomic codes do. We finally use the optimal 2 x 2 diagonal space-time codes from the optimal quadratic extensions to construct two 2 x 2 full-rate space-time block codes and find that both of them have better normalized diversity products than the Golden code does.

关键词： Algebraic extension complex lattice Golden code normalized diversity product space-time block code

来源：评论

学校读者我要写书评

暂无评论

A Novel Transmit Diversity Scheme Based on CR-QOSTBC and MC-CDMA

A Novel Transmit Diversity Scheme Based on CR-QOSTBC and MC-...

引用

2010年通信理论与信号处理学术年会

作者： GUO Ai-huang LUO Wei SHANG Xiu-hui CAO Wen-jia School of Electronics and Information Engineering Tongji UniversityShanghai 200092hina State Key L School of Electronics and Information Engineering Tongji UniversityShanghai 200092hina

space-time block codes (STBCs) play an important role in spatial diversity *** Alamouti scheme provides full diversity, full rate and needs simple separating decoding but is for only two *** more than two antennas, qtasi-orthogonal space-time block codes (QOSTBCs) are able to provide full rate but enjoy only a partial diversity and need pairwise *** recently proposed constellation-rotated QOSTBCs (CR-QOSTBCs) can achieve both full diversity and full *** this paper, we propose a novel transmit diversity scheme based on CR-QOSTBC and multi-carrier code division multiple access (MC-CDMA), using four transmit antennas and one receive antenna, which not only provides full diversity and full rate but also uses simple decoding, achieves good performance in frequency selective fading channels due to the ability of diversities in space, time, frequency and *** simulation is then complimented to show that the bit error rate (I3ER) performance of CR-QOSTBC-MC-CDMA to is improved distinctly.

关键词： comunication and information system space-time block code constellation-rotated quasi-orthogonal space-time block code multi-carrier code division multiple access full rate full diversity

来源：评论

学校读者我要写书评

暂无评论

A Novel Transmit Diversity Scheme Based on CR-QOSTBC and MC-CDMA

A Novel Transmit Diversity Scheme Based on CR-QOSTBC and MC-...

引用

中国通信学会通信理论与信号处理专业委员会2010年通信理论与信号处理学术年会

作者： GUO Ai-huang~(1,2) LUO Wei~(1,2) SHANG Xiu-hui~(1,2) CAO Wen-jia~1 (1.School of Electronics and Information Engineering,Tongji University,Shanghai 200092,hina 2.State Key Laboratory of Millimeter Waves,Nanjing 210096,China )

space-time block codes(STBCs) play an important role in spatial diversity technologies. The Alamouti scheme provides full diversity,full rate and needs simple separating decoding but is for only two *** more than two antennas,quasi-orthogonal space-time block codes(QOSTBCs) are able to provide full rate but enjoy only a partial diversity and need pairwise *** recently proposed constellation-rotated QOSTBCs(CR-QOSTBCs) can achieve both full diversity and full rate. In this paper,we propose a novel transmit diversity scheme based on CR-QOSTBC and multi-carrier code division multiple access(MC-CDMA),using four transmit antennas and one receive antenna, which not only provides full diversity and full rate but also uses simple decoding,achieves good performance in frequency selective fading channels due to the ability of diversities in space,time, frequency and *** simulation is then complimented to show that the bit error rate(BER) performance of CR-QOSTBC-MC-CDMA to is improved distinctly.

来源：评论

学校读者我要写书评

暂无评论

Performance of MIMO System Through Nakagami Fading Channel with Arbitrary Fading Parameters

引用

WIRELESS PERSONAL COMMUNICATIONS 2009年第3期50卷 367-380页

作者： Saaifan, Khodr A. Al-Hussaini, Emad K. Cairo Univ Fac Engn Elect & Commun Dept Giza 12613 Egypt

In this paper, the analytical and simulation results of the bit error rate (BER) performance for a multiple-input multiple-output (MIMO) system with an arbitrary number of transmit and receive antennas are developed for the uplink transmission. The fading channel is assumed to follow Nakagami-m distribution with correlation among branches. The BER is expressed in terms of Lauricella's multivariate hypergeometric function for both independent and correlated antenna branches for BPSK system.

关键词： MIMO systems Correlated Nakagami fading channels space diversity space-time block code

来源：评论

学校读者我要写书评

暂无评论

Performance of Alamouti's OSTBC with Channel Estimation

引用

IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES 2009年第11期E92A卷 2844-2850页

作者： Ohno, Shuichi Hiroshima Univ Grad Sch Engn Dept Artificial Complex Syst Engn Higashihiroshima 7398527 Japan

Alamouti's orthogonal space-time block code (OSTBC) is a simple yet important technique to take advantage of transmit diversity to mitigate fading channel effects. In this paper, we analyze the effects of time-selective channels and channel estimation errors on the bit error rate (BER) performance of Alamouti's OSTBC. We develop an analytical expression of the BER performance for the linear decoding with minimum mean squared error (MMSE) channel estimates in place of the true channel. Based on the expression. we derive a BER performance limit in decision-directed mode where the channel is tracked with Kalman filtering Numerical examples are provided to validate our analysis and to see the impact of time-selective fading and channel estimation errors on the BER performance.

关键词： space-time block code time-selective fading channel tracking Kalman filter

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：