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Fast blind channel estimation for space-time block coded MIMO-OFDM systems

TELECOMMUNICATION SYSTEMS 2017年第3期65卷 443-457页

作者： Zhang, Biling Yu, Jung-Lang Yuan, Yipu Lai, Jian-Wei Beijing Univ Posts & Telecommun Sch Network Educ Beijing 100876 Peoples R China Xidian Univ State Key Lab Integrated Serv Networks Xian 710071 Peoples R China Fu Jen Catholic Univ Dept Elect Engn New Taipei 24205 Taiwan Fu Jen Catholic Univ Grad Inst Appl Sci & Engn New Taipei 24205 Taiwan Quanzhou Normal Univ Coll Phys & Informat Engn Quanzhou 362000 Peoples R China

Fast blind subspace channel estimation using circular property of the channel matrix is investigated for space-time block coded (STBC) multiple-input multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) systems in this paper. The noise subspace computed from the correlation matrix of received signals requires a large number of symbols to converge in the subspace channel estimation. Using the circular property of the channel matrix, we propose both the cyclic repetition method (CRM) and the forward-backward method (FBM) to generate N times of equivalent signals for each STBC-OFDM symbol, respectively, where N is the size of FFT operation. With these equivalent symbols, the proposed CRM, FBM and CRM-FBM (CFBM) channel estimations can perform very well within a few OFDM symbols. The CRM, FBM and CFBM schemes are applicable to the CP-OFDM, ZP-OFDM and VC-OFDM systems, respectively. The identifiability of the subspace channel estimation is investigated that the channel matrix is determined up to two ambiguity matrices. Computer simulations demonstrate that the CRM-based, FBM-based and CFBM-based channel estimations have better performances than the conventional ones.

关键词： space-time block code MIMO-OFDM Blind channel estimation Cyclic prefix Virtual carrier Zero-padding

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Performance Analysis of a Free space Optical Link using Alamouti Type space time block code with Weak Turbulent Condition

Performance Analysis of a Free Space Optical Link using Alam...

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7th International Conference on Electrical and Computer Engineering

作者： Islam, M. Shariful Majumder, S. P. Ahsanullah Univ Sci & Technol Dept Elect & Elect Engn Dhaka Bangladesh

ISBN: (纸本)9781467314343;9781467314350

In this paper, we investigate the performance of a free space optical link using Alamouti type space time block code (STBC) over weak atmospheric turbulence-induced fading channels. An analytical approach is presented to evaluate the bit error rate (BER) performance of a direct detection on-off keying (OOK) free space optical link over a weak atmospheric turbulent condition considering Alamouti type space time block code (STBC) and maximal ratio combining (MRC) at the receiver. The results are evaluated numerically and also by simulation. Results show that there is significant improvement in BER performance at a given BER due to coding and diversity combining at the receiver. The amount of improvement for (M X L) STBC is of the order of 18 dB, 10 dB and 5 dB for laser source, M=2 and number of photodetector, L = 1, 2 and 4 respectively.

关键词： Multiple Input Multiple Output Bit Error Rate space-time block code Transmit Diversity Free space Optic Maximal Ratio Combining

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MIMO GS OVSF/OFDM Based Underwater Acoustic Multimedia Communication Scheme

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WIRELESS PERSONAL COMMUNICATIONS 2018年第2期101卷 601-617页

作者： Lin, Chin-Feng Lai, Hsiu-Hung Chang, Shun-Hsyung Natl Taiwan Ocean Univ Dept Elect Engn Keelung Taiwan Natl Kaohsiung Univ Sci & Technol Dept Microelect Engn Kaohsiung Taiwan

An underwater acoustic multimedia communication (UWAMC) system is proposed with 2400 transmission modes according to time-varying multipath underwater acoustic (UWA) channel conditions. The orthogonal variable spreading factor (OVSF) scheme and Gold sequence (GS) scramble code are integrated into multi-input multi-output UWAMC system based on orthogonal frequency-division multiplexing to achieve the quality of service of multimedia transmission in the UWA channel. Binary phase shift keying (BPSK) and quadrature phase shift keying (QPSK) adaptive modulation, direct mapping (DM) or space-time block code (STBC) transmission strategies, convolution channel code with rate 1/2 and 1/3, and a power assignment mechanism were adopted in the proposed system. Simulation results show that the bit error rate (BER) and power saving ratio (PSR) performance of the STBC strategy with transmission diversity is superior to that of the DM strategy without transmission diversity, and the performance of the BERs and PSRs of the transmission scheme with the GS scramble code surpasses that of the scheme without the code. The performance of the BERs and PSRs of BPSK modulation with a channel code rate of 1/3 is better than that of BPSK modulation with a channel code rate of 1/2, and the performances of BERs and PSRs of BPSK modulation with a channel code rate of 1/3 are better than that of QPSK modulation with a channel code rate of 1/3. As the length of the OVSF codes increases, the UWAMC system's BERs decrease, and its PSRs increase. The UWAMC system can achieve either maximum transmission speed or maximum transmission power efficiency.

关键词： Underwater acoustic multimedia communication Orthogonal variable spreading factor Gold sequence space-time block code Bit error rates Power saving ratios

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How to obtain lattices from (f, σ, δ)-codes via a generalization of Construction A

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APPLICABLE ALGEBRA IN ENGINEERING COMMUNICATION AND COMPUTING 2018年第4期29卷 313-333页

作者： Pumplun, S. Univ Nottingham Sch Math Sci Univ Pk Nottingham NG7 2RD England

We show how cyclic -codes over finite rings canonically induce a -lattice in by using certain quotients of orders in nonassociative division algebras defined using the skew polynomial f. This construction generalizes the one using certain -constacyclic codes by Ducoat and Oggier, which used quotients of orders in non-commutative associative division algebras defined by f, and can be viewed as a generalization of the classical Construction A for lattices from linear codes. It has the potential to be applied to coset coding, in particular to wire-tap coding. Previous results by Ducoat and Oggier are obtained as special cases.

关键词： space-time block code Linear (f, sigma, delta)-code Nonassociative algebra Coset coding Wiretap coding Construction A Order Skew polynomial ring

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Multi-taper spectrum-based estimator for cognitive radio using multiple antennas and STBC techniques

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IET CIRCUITS DEVICES & SYSTEMS 2018年第2期12卷 133-143页

作者： Salam, Ahmed O. Abdul Sheriff, Ray E. Al-Araji, Saleh R. Mezher, Kahtan Nasir, Qassim Univ Bradford Sch Elect Engn & Comp Sci Fac Engn & Informat Bradford BD7 1DP W Yorkshire England Khalifa Univ Elect & Comp Engn Dept Coll Engn POB 127788 Abu Dhabi U Arab Emirates Univ Sharjah Elect & Comp Engn Dept Coll Engn POB 27272 Sharjah U Arab Emirates

An effective approach for the design of spectrum estimation (SE) in cognitive radio systems using multi-taper method (MTM) and spatiotemporal features is presented in this study, whereas the MTM balances the bias-variance dilemma, the multiple-input-multiple-output (MIMO) and space-time block code (STBC) are customarily aimed to defeat the adverse channel effects and enhance the system capacity and performance. The singular value decomposition is exploited to determine the dominant eigenchannels in MIMO and STBC setups. The maximum-ratio combining, on the other hand, is adopted to produce higher signal-to-noise ratios usually intended for high data rates and reliability levels. The statistical analysis and modelling of the performance metrics associated with the SE based on MTM-STBC and MIMO are approached using the quadratic form approximation. Simulation exercises are employed to compare this different SE, which will be called multitaper spectrum estimation (MTSE), against other typical methods such as the periodogram without tapering options. The results exhibit performance gains due to the merger of MTSE and STBC technologies over MIMO and periodogram SE (PSE) algorithms. Further computational analysis shows that the MTSE-STBC has no extra burdens compared with its PSE counterpart.

关键词： cognitive radio antenna arrays space-time block codes channel coding radio spectrum management MIMO communication singular value decomposition channel estimation diversity reception eigenvalues and eigenfunctions statistical analysis approximation theory multitaper spectrum-based estimator multiple antennas STBC techniques SE design cognitive radio systems MTM spatiotemporal features bias-variance dilemma multiple-input-multiple-output channel space-time block code channel effects system capacity enhancement singular value decomposition performance enhancement dominant eigenchannels maximum-ratio combining higher signal-to-noise ratios high data rates reliability levels statistical analysis performance metrics quadratic form approximation MTSE periodogram SE algorithms PSE algorithms

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space-time Line code

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IEEE ACCESS 2018年 6卷 1023-1041页

作者： Joung, Jingon Chung Ang Univ Sch Elect & Elect Engn Seoul 06974 South Korea

This paper characterizes rate-one (i.e., full rate) full-spatial-diversity-achieving communication schemes based on the channel state information (CSI) availability and antenna configurations, i.e., CSI at a transmitter (CSIT) or CSI at a receiver (CSIR) and the numbers of transmit and receive antennas M and N (denoted by M x N), respectively. The maximum ratio combining (MRC), maximum ratio transmission (MRT), and space-time block code (STBC) schemes are rate-one full-spatial-diversity-achieving method facilitated for communication systems with: 1) 1 x N and CSIR;2) M x 1 and CSIT;and 3) M x 1 and CSIR, respectively. A novel space-time line code (STLC) is then introduced for a 1 x 2 system with CSIT, and it is extended to an M x 2 STLC. The proposed STLC uses CSI for encoding at the transmitter and enables the receiver to decode the STLC symbols without CSI. Also, the STLC encoding matrices with various code rates and decoding (combining) schemes are designed for the M x 3 and M x 4 STLC systems: A code rate of 3/4, 1/2, and 3/7 for the M x 3 systems and a code rate of 3/4, 4/7, and 1/2 for the M x 4 systems. For each STLC scheme, a full-diversity achieving STLC decoding method is designed. Based on analyses and numerical results, we verify that the proposed STLC scheme achieves a full diversity order, i.e., MN, and is robust against CSI uncertainty. It is also shown that the array processing gain is inversely proportional to the code rate. To verify the merit of STLC, we introduce a joint operation with STBC and STLC schemes, called an STBLC system. The STBLC system achieves full-spatial-diversity gain in both uplink and downlink communications. The new STLC achieving full-spatial diversity is scalable for various code rates and expected to be applied to various wireless communication systems along with MRC, MRT, and STBC.

关键词： space-time code space-time block code space-time line code spatial diversity gain multiple antennas

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Channel Estimation for space-time block coded OFDM Systems using Few Received Symbols 7

Channel Estimation for Space-Time Block Coded OFDM Systems u...

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7th International Joint Conference on Pervasive and Embedded Computing and Communication Systems (PECCS)

作者： Zhang, Biling Yuan, Yipu Yu, Jung-Lang Hsu, Wei-Ting Huang, Yu-Jie Beijing Univ Posts & Telecommun Sch Network Educ Beijing 100876 Peoples R China Quanzhou Normal Univ Coll Phys & Informat Engn Quanzhou 362000 Peoples R China Fu Jen Catholic Univ Dept Elect Engn New Taipei 24205 Taiwan

ISBN: (纸本)9789897582660

A novel subspace channel estimation is proposed for space-time block coded (STBC) multiple-input multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) systems. Considering the zero-padding technique, the signal model of the STBC-OFDM system is first studied. The major drawback of the subspace method is the slow convergence which requires a large number of received symbols to compute the noise subspace. The repetition index scheme is developed here to increase the number of equivalent received symbols. Using the space-time coding property, the forward-backward method is presented to improve the convergence speed further. Moreover, the repetition index scheme transforms the white noise into non-white one. The noise prewhitening technique is proposed to reduce the non-white noise effect. Computer simulations show the effectiveness of the proposed forward-backward method and noise prewhitening technique.

关键词： space-time block code Multiple-Input Multiple-Output Orthogonal Frequency Division Multiplexing Subspace Channel Estimation Forward-backward Method Noise Prewhitening Technique

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Performance Analysis of Orthogonal space-time block codes Over Nakagami-? (Hoyt) MIMO RFID Backscattering Channels

Performance Analysis of Orthogonal Space-time Block Codes Ov...

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作者： Yasmin Hisham Tawfiq Qabbani Al-Quds University

学位级别：硕士

Radio frequency identification (RFID) is an automatic identification technology which utilizes radio-frequency electromagnetic fields to identify objects carrying tags in the reading range of a reader. Such identification over a wireless channel doesn't necessitate the tag and the reader being in physical contact or line-of-sight (LOS) aligned. This preferable feature of sending identification data wirelessly may adversely affect the performance of the RFID system, because even when LOS path exists, heavy small-scale fading may still be present due to indoor operation, a cluttered reader environment, and the inhomogeneous nature of the tagged object. To mitigate this fading problem and increase the read reliability, space-time block coding (STBC) for multiple-input multiple-output (MIMO) RFID systems is suggested and employed. In this thesis, a performance analysis of orthogonal space-time block codes (OSTBC) in passive MIMO RFID system is conducted. More particularly, the conditional moment-generating function (MGF) approach is employed to analyse the performance of OSTBC over Nakagami- (Hoyt) MIMO RFID backscattering channels. New exact and asymptotic closed-form symbol error rate (SER) expressions are derived for the case of two and four reader-receiving antennas. The diversity order that the system can achieve is found to be, where is the number of tag antennas, and the performance of this channel is found to be more sensitive to the channel condition (the parameter) of the forward link than that of the backscattering link. A good agreement with previous published studies was observed for the special case that the Hoyt fading covers.

关键词： backscattering cascaded structure Nakagami-(Hoyt) fading radiofrequency identification multiple-input multiple-output symbol error rate diversity gain space-time block code

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On the criteria for designing complex orthogonal space-time block codes

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Science China(Information Sciences) 2016年第8期59卷 153-163页

作者： Haibin KAN Xiaodong LIU Guangyue HAN School of Computer Science Fudan University Shanghai Key Laboratory of Intelligent Information Processing Fudan University Department of Mathematics University of Hong Kong

A complex orthogonal design(COD) used in space-time block codes is a kind of combinatorial design. It has been well studied because it has a fast maximum-likelihood decoding algorithm and achieves full diversity. When designing CODs, there are seven characteristics that should be considered, which include code rate, decoding delay, transceiver signal linearization, peak-to-average power ratio, etc. In this paper, we study the relationships among these design criteria. We prove that the maximum rate of generalized CODs(GCODs)that meet the last five criteria is 1/2. Moreover, we present a new method to construct GCODs based on *** this method on balanced complex orthogonal designs(BCODs), we obtain a novel class of GCODs that performs almost perfectly with respect to all the seven properties.

关键词： space-time block code complex orthogonal design decoding delay transceiver signal linearization peak-to-average power ratio(PAPR)

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An investigation of wireless S-DF hybrid satellite terrestrial relaying network over time selective fading channel

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TRAITEMENT DU SIGNAL 2018年第2期35卷 103-120页

作者： Kumar, Indrajeet Sachan, Vikash Shankar, Ravi Mishra, Ritesh Kumar Natl Inst Technol Patna Dept Elect & Commun Engn Patna 800005 Bihar India

This work investigates the performance of hybrid satellite terrestrial cooperative relaying communications network (HSTCN) over time-selective fading links arising due to the node mobility. Both satellite-to-destination (SD) and Satellite-to-relay (SR) links undergo the independent and identically distributed (i.i.d.) time-selective shadowed Rician fading, the terrestrial relay-to-destination links are assumed to be i.i.d. time-selective Nakagami-m faded. It evaluates the performance of such a network using multiple-input multiple-output (MIMO) space-time block-code (STBC) based selective decode forward (S-DF) cooperation with imperfect CSI. An analytical approach is derived to evaluate the performance of the system in terms of per-frame average pairwise error probability (PEP) and asymptotic PEP floor. Further, a framework is developed for deriving the diversity order (DO). It demonstrates that full DO for cooperation protocol can be achieved when there is a knowledge of perfect CSI. A convex optimization (CO) framework is formulated for obtaining the optimal source-relay power allocation factors which significantly improve the end-to-end reliability of the system under power constraint scenarios. The results show the time selective nature of the links and imperfect CSI significantly degrades the system performance. Further, the impact of the satellite elevation angles at the terrestrial nodes is explicitly demonstrated through simulations. The error rate of the system is seen to reduce significantly with increasing satellite elevation angle at the relay when the SD link experiences frequent heavy shadowing and the RD links are relatively strong. However, for other scenarios when the RD links are relatively weak and SR links experience frequent heavy shadowing, significant performance improvement can be seen by increasing, the satellite elevation angle at the destination user equipment. The analytical expressions show excellent agreement with the simulation results

关键词： node mobility selective decode-forward space-time block code pairwise error probability hybrid satellite network

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