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Performance of Dualbeam MIMO for Millimeter Wave Indoor Communication Systems

WIRELESS PERSONAL COMMUNICATIONS 2014年第1期77卷 289-307页

作者： Kirthiga, S. Jayakumar, M. Amrita Vishwa Vidyapeetham Dept Elect & Commun Engn Commun Engn Res Grp Coimbatore Tamil Nadu India

Millimeter wave (MMW) communication provides high data rates for the personal area networks with the availability of 57-64 GHz unlicensed spectrum, in indoor environment. Multipath fading being pre-dominant in indoor, multi input multi output (MIMO) technology is considered to be the ideal choice compared with the existing systems. As spatial diversity in both transmit and receive enhances the diversity gain, the performance of the system is further enhanced by introducing transmit beamforming based antenna beam diversity. In classical MIMO, a diversity gain of 4 is achieved, whereas in this work, space time block code matrix of code rate 1/2 and dualbeam MIMO with diversity gain 8 is considered. Dualbeam is generated by antenna array with four elements per array with out of phase feed configuration. The weight vector of the beamforming network is out of phase as to reduce the interference between the beams. The dualbeam transmitter is designed with unknown channel state information. Training symbols are transmitted to train and track the channel statistics at the receiver. The proposed work is carried out for MMW indoor system. The indoor channel is modeled using Triple Saleh-Valenzuela (TSV) model that takes into account both time of arrival and the angle of arrival information of the rays. Channel estimation is done for classical MIMO and the above proposed model in both Rayleigh and TSV channel. The orthogonal beams facilitate linear processing in the receiver. Hence maximum ratio combiner with maximum likelihood decoder is used in the receiver to decode the transmitted data. Classical MIMO and dualbeam MIMO are evaluated with respect to bit error rate and channel models. An improved diversity order is achieved with dualbeam MIMO compared to classical MIMO, with a power gain of 1.6 dB. The dualbeam MIMO using TSV is found to perform better compared to dualbeam MIMO using Rayleigh in the low Energy per bit to Noise level with a power gain of 2 dB.

关键词： Millimeter wave MIMO space time block code Dualbeam Triple Saleh Valenzuela Maximal ratio combiner Maximum likelihood

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Bit Error Rate Analysis for V-BLAST/STBC using Interference Cancellation Techniques

Bit Error Rate Analysis for V-BLAST/STBC using Interference ...

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16th International Conference on Advanced Communication Technology (ICACT)

作者： Kotchasarn, Chirawat Rajamangala Univ Technol Thanyaburi Dept Elect & Telecommun Engn Pathumthnani 12110 Thailand

ISBN: (纸本)9788996865032

Multiple Input Multiple Output (MIMO) systems have been extensively studied in context of wireless communication systems, which promising the both increased capacity and link level reliability. In this paper, we proposed the interference cancellation techniques for VBLAST/STBC architecture, which integrates Alamouti space-time block code (STBC) layer together with vertical Bell-laboratories (V-BLAST) layer. In this work, we employ four transmit and three receive antennas over frequency flat Rayleigh fading channel. This paper presents signal detectors for V-BLAST/STBC with minimum mean square error (MMSE), zero forcing (ZF), parallel interference cancellation (PIC) and successive interference cancellation-zero forcing with binary phase shift keying (BPSK). Simulation results show the bit error rate performance degradation and the computational complexity of the joint optimal detection is better than the other detection technique.

关键词： interference cancellation Vertical Bell Laboratories Layered space-time space time block code zero forcing minimum mean square error successive interference cancellation parallel interference cancellation

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Single-Symbol Maximum Likelihood Decodable STBCs with Fewer Zero-Entries

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WIRELESS PERSONAL COMMUNICATIONS 2013年第2期69卷 827-839页

作者： Van-Bien Pham Sheng, Weixing Wang, Mao Shu, Feng Ma, Xiaofeng Nanjing Univ Sci & Technol Dept Commun Engn Nanjing 210094 Jiangsu Peoples R China Nanjing Univ Sci & Technol Inst Wireless Commun & Sensor Network Nanjing 210094 Jiangsu Peoples R China

Two generalized constructions of single-symbol maximum likelihood (ML) decodable space-time block codes (SSDCs), the coordinate interleave orthogonal design (CIOD) and the generalized CIOD (GCIOD), have been proposed by Khan et al. Their main disadvantage is that there are too many zero entries in the codeword matrix. The transmission of these zero-valued symbols causes switching off some of the transmit antennas resulting in a high peak-to-average power ratio and also imposing a severe constraint on hardware implementation of the code. Based on the orthogonal construction of orthogonal space-time block codes and coordinate interleaving, a new generalized construction of SSDCs is proposed. Our proposed codes not only maintain the desirable properties of high rate, full transmit diversity and single-symbol ML decoding similar to CIODs and GCIODs, but also have fewer zero entries in its codeword matrix than CIODs and GCIODs.

关键词： MIMO systems space time block code Single-symbol decoding Transmit diversity

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SAGE Algorithm for Semi-Blind Channel Estimation and Symbol Detection for STBC MIMO OFDM Systems

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WIRELESS PERSONAL COMMUNICATIONS 2013年第2期71卷 1541-1555页

作者： Hedayati, Mohsen Keshavarz Bakhshi, Hamidreza Cheraghi, Mehdi Shahed Univ Dept Elect Engn Tehran Iran

In this paper, a novel semi-blind channel estimation and symbol detection based on space-alternating generalized expectation-maximization (SAGE) algorithm are proposed for space time block coded (STBC) multiple input multiple output orthogonal frequency division multiplexing (MIMO-OFDM) systems. At the receiver, the transmitted signals of all users are added. By utilization of SAGE algorithm, this superimposed received signals are decomposed into their signal components. Then, the channel is estimated at pilot positions. After that, the channel estimation in the other positions are obtained by interpolation and symbol detection is done by utilizing the estimated channel. In SAGE algorithm, selection of initial value is very important for the convergence. We discuss the appropriate range for selection of initial value in this paper. Simulation results show that by increasing the number of users, the slope of bit error rate curve increases with same initial value and the channel estimation becomes worse by increasing the iteration of SAGE algorithm if the initial value is not selected in the proposed rang.

关键词： SAGE MIMO-OFDM space time block code Semi-blind channel estimation

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Deception jammer rejection using pulse diversity in joint slow/fast-time domain

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JOURNAL OF THE CHINESE INSTITUTE OF ENGINEERS 2013年第3期36卷 405-410页

作者： Lu, Gang Tang, Bin Xihua Univ Sch Elect & Informat Engn Chengdu 610039 Peoples R China Univ Elect Sci & Technol China Sch Elect Engn Chengdu 611731 Peoples R China

In this article, a method based on the theory of pulse diversity is presented for rejecting a deception jammer which is repeated by a digital radio frequency memory. The application conditions involved in slow-time approach, which cancels the jammer across several pulse repetition intervals, is restricted to the hypothesis that the reflectors and reflectivity levels remain stationary making it impractical in rapidly varying conditions. This issue is resolved through producing new vectors from the original transmission signals in joint slow/fast-time domain. Moreover, the presented method also insures satisfactory performance levels when the target and jamming pulses are overlapped.

关键词： electronic counter-countermeasures digital radio frequency memory false target space time block code

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Effect on Performance of Wireless Uplink for Placing Decode and Forward MIMO Relay At Different Position Between Source and Destination

Effect on Performance of Wireless Uplink for Placing Decode ...

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International Conference on Electrical Information and Communication Technology (EICT)

作者： Kamruzzaman, M. M. Southwest Jiaotong Univ Key Lab Informat Coding & Transmiss Chengdu Sichuan Peoples R China

ISBN: (纸本)9781479922994

This paper investigates the effect on performance for placing a decode and forward MIMO relay at different position between source and destination for wireless uplink in the presence of rayleigh fading where source is equipped with single transmit antenna, relay is equipped with multiple transmit and receive antennas, and destination has multiple receive antennas. It is observed that relay at 0.4 and/or 0.5 and/or 0.6 provides best performance. On the other hand, relay at 0.2 and/or 0.8 shows the worst performance. That is, the system shows the best performance placing relay at the middle of the source and the destination, or slightly closer to middle. And the system shows the worse performance placing relay close to the source or the destination. It is also observed that relay at 0.4 or 0.5 or 0.6 provides 5 dB to 12 dB gains at 10(-5) compared to relay at 0.2 or 0.8.

关键词： space time block code MIMO Relay Decode and Forward Uplink Wireless Communication

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A space time block code from Quaternion Quasi-Orthogonal Design

A Space Time Block Code from Quaternion Quasi-Orthogonal Des...

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4th International Conference on Wireless Communications, Networking and Mobile Computing

作者： Li Zhengquan Wang Zigang Yangzhou Univ Dept Elect & Commun Yangzhou 225009 Peoples R China

In this paper we introduce a new kind of space time block code based on quaternion quasi-orthogonal design. The new code can transmitted through dual-polarized antennas and received through dual-polarized antennas. Co... 详细信息

ISBN: (纸本)9781424421077

关键词： space time block code quasi-orthogonal bit error rate

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MIMO System Optimization Using STTC Based STBC with Channel Estimation

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WIRELESS PERSONAL COMMUNICATIONS 2012年第1期66卷 147-165页

作者： Sharma, Sameru Sharma, Sanjay Engles, Derick Govt Coll Engn & Technol Jammu India Power Dev Dept Jammu India GND Univ Amritsar Punjab India

We propose a new architecture involving space time trellis code (STTC) concatenated with space time block code (STBC) using modified sphere decoder (MSD-1) at the receiver for improving system performance in the multi-antenna environment. With the aim of increasing the 'Diversity Order' of signal set, rotated versions of quadrature amplitude modulation (QAM) constellation have been used in multidimensional space and the associated design parameters required to search an effective signal constellation have been optimized. The limitations on account of complexity owing to multiple copies of data being received after experiencing various channel effects in the multi input multi output (MIMO) systems have been looked into. Accordingly, MSD-1 algorithm has been proposed with lower complexity, which in turn would give rise to a system with high spectral efficiency. The system gains have been verified with channel state information (CSI) errors.

关键词： Diversity Multi-antenna Rotated constellation space time trellis code space time block code

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Two Novel Rate-One Fast-Decodable space time block codes for Four Transmit Antennas

Two Novel Rate-One Fast-Decodable Space Time Block Codes for...

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Iranian Conference on Electrical Engineering

作者： Sam Ranjbar Vahid Tabataba Vakily School of Electrical Engineering Iran University of Science &Technology School of Electrical Engineering Iran University of Science & Technology

ISBN: (纸本)9781467311496

This paper deals with two new rate-one, full-diversity space time block codes for four transmit antennas and one receive antenna. The proposed designs add extra symbol to the rate 3/4 OSTBC for four transmit antennas with different strategies to make OSTBC rate-one and ensuring full-diversity. Also in this paper it is shown that the proposed STBCs are fast-decodable with QR decomposition. Simulation results show that proposed STBCs have better performance than other proposed designs. This idea is also proposed in [8] and [9] before, but in these works the authors do not consider larger signal constellation or do not optimize the coding gain.

关键词： space time block code Fading Full-diversity Fast-decodable OSTBC

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Performance of Decode and Forward MIMO Relaying for Wireless Uplink

Performance of Decode and Forward MIMO Relaying for Wireless...

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15th International Conference on Computer and Information Technology (ICCIT)

作者： Kamruzzaman, M. M. Southwest Jiaotong Univ Key Lab Informat Coding & Transmiss Chengdu Sichuan Peoples R China

ISBN: (纸本)9781467348362;9781467348331

In this paper, performance of relay assisted wireless link is evaluated in the presence of rayleigh fading where mobile handset is equipped with single transmit antenna, relay is equipped with multiple transmit and receive antennas, and destination has multiple receive antennas. Data are modulated using QPSK or 16 QAM or 64 QAM modulator at handset and send to relay which combined and decode the incoming signal using Maximum Likelihood decoding and further encode the symbols using STBC, and the encoded data are split into n streams which are simultaneously transmitted using n transmit antennas of relay. It is observed that relay with 2 transmit antennas and 2,3,4,5 and 6 receive antennas provides 13 dB, 11 dB, 9 dB, 6 dB and 5 dB gains respectively compared to direct link at 10-5. And there are around 1.5 dB to 6 dB gains for increasing number of receiving antennas of relay from 2 to 3 or 3 to 4 but there are very little gains for increasing number of receiving antennas of relay from 4 to 5 or 5 to 6.

关键词： space time block code MIMO Relay Decode and Forward Uplink Wireless Communication

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