Dissertations / Theses on the topic 'Space-time coding'
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Lamahewa, Tharaka Anuradha, and tharaka lamahewa@anu edu au. "Space-Time Coding and Space-Time Channel Modelling for Wireless Communications." The Australian National University. Research School of Information Sciences and Engineering, 2007. http://thesis.anu.edu.au./public/adt-ANU20070816.152647.
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In this thesis we investigate the effects of the physical
constraints such as antenna aperture size, antenna geometry and
non-isotropic scattering distribution parameters (angle of
arrival/departure and angular spread) on the performance of coherent
and non-coherent space-time coded wireless communication systems.
First, we derive analytical expressions for the exact pairwise error
probability (PEP) and PEP upper-bound of coherent and non-coherent
space-time coded systems operating over spatially correlated fading
channels using a moment-generating function-based approach. These
analytical expressions account for antenna spacing, antenna
geometries and scattering distribution models. Using these new PEP
expressions, the degree of the effect of antenna spacing, antenna
geometry and angular spread is quantified on the diversity advantage
(robustness) given by a space-time code. It is shown that the number
of antennas that can be employed in a fixed antenna aperture without
diminishing the diversity advantage of a space-time code is
determined by the size of the antenna aperture, antenna geometry and
the richness of the scattering environment.
¶
In realistic channel environments the performance of space-time
coded multiple-input multiple output (MIMO) systems is significantly
reduced due to non-ideal antenna placement and non-isotropic
scattering. In this thesis, by exploiting the spatial dimension of a
MIMO channel we introduce the novel use of linear spatial precoding
(or power-loading) based on fixed and known parameters of MIMO
channels to ameliorate the effects of non-ideal antenna placement on
the performance of coherent and non-coherent space-time codes. The
spatial precoder virtually arranges the antennas into an optimal
configuration so that the spatial correlation between all antenna
elements is minimum. With this design, the precoder is fixed for
fixed antenna placement and the transmitter does not require any
feedback of channel state information (partial or full) from the
receiver. We also derive precoding schemes to exploit non-isotropic
scattering distribution parameters of the scattering channel to
improve the performance of space-time codes applied on MIMO systems
in non-isotropic scattering environments. However, these schemes
require the receiver to estimate the non-isotropic parameters and
feed them back to the transmitter.
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The idea of precoding based on fixed parameters of MIMO channels is
extended to maximize the capacity of spatially constrained dense
antenna arrays. It is shown that the theoretical maximum capacity
available from a fixed region of space can be achieved by power
loading based on previously unutilized channel state information
contained in the antenna locations. We analyzed the correlation
between different modal orders generated at the transmitter region
due to spatially constrained antenna arrays in non-isotropic
scattering environments, and showed that adjacent modes contribute
to higher correlation at the transmitter region. Based on this
result, a power loading scheme is proposed which reduces the effects
of correlation between adjacent modes at the transmitter region by
nulling power onto adjacent transmit modes.
¶
Furthermore, in this thesis a general space-time channel model for
down-link transmission in a mobile multiple antenna communication
system is developed. The model incorporates deterministic
quantities such as physical antenna positions and the motion of the
mobile unit (velocity and the direction), and random quantities to
capture random scattering environment modeled using a bi-angular
power distribution and, in the simplest case, the covariance between
transmit and receive angles which captures statistical
interdependency. The Kronecker model is shown to be a special case
when the power distribution is separable and is shown to
overestimate MIMO system performance whenever there is more than one
scattering cluster. Expressions for space-time cross correlations
and space-frequency cross spectra are given for a number of
scattering distributions using Gaussian and Morgenstern's family of
multivariate distributions. These new expressions extend the
classical Jake's and Clarke's correlation models to general
non-isotropic scattering environments.
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Lamahewa, Tharaka Anuradha. "Space-time coding and space-time channel modelling for wireless communications /." View thesis entry in Australian Digital Theses Program, 2006. http://thesis.anu.edu.au/public/adt-ANU20070816.152647/index.html.
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Liew, Tong Hooi. "Channel coding and space-time coding for wireless channels." Thesis, University of Southampton, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.341591.
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Acharya, Om Nath, and Sabin Upadhyaya. "Space Time Coding For Wireless Communication." Thesis, Linnéuniversitetet, Institutionen för datavetenskap, fysik och matematik, DFM, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-19424.
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As the demand of high data rate is increasing, a lot of research is being conducted in the field of wireless communication. A well-known channel coding technique called Space-Time Coding has been implemented in the wireless Communication systems using multiple antennas to ensure the high speed communication as well as reliability by exploiting limited spectrum and maintaining the power. In this thesis, Space-Time Coding is discussed along with other related topics with special focus on Alamouti Space-Time Block Code. The Alamouti Codes show good performance in terms of bit error rate over Rayleigh fading channel. The performance of Altamonte’s code and MIMO capacity is evaluated by using MATLAB simulation.
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Jensen, Michael A., and Michael D. Rice. "SPACE-TIME CODING FOR WIRELESS COMMUNICATIONS." International Foundation for Telemetering, 2002. http://hdl.handle.net/10150/605605.
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International Telemetering Conference Proceedings / October 21, 2002 / Town & Country Hotel and Conference Center, San Diego, CaliforniaSignal fading and intersymbol interference created by multipath propagation have traditionally limited the throughput on wireless communications systems. However, recent research has demonstrated that by using multiple antennas on both transmit and receive ends of the link, the multipath channel can actually be exploited to achieve increased communication throughput over single-antenna systems. This paper provides an introductory description of such multi-antenna communications systems, focusing on basic explanations of how they achieve capacity gains. Computed and measured capacity results are used to demonstrate the potential of these systems.
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Nelson, N. Thomas. "Space-Time Coding with Offset Modulations." Diss., CLICK HERE for online access, 2007. http://contentdm.lib.byu.edu/ETD/image/etd2155.pdf.
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Yiu, Simon Tik-Kong. "Distributed space-time coding for cooperative networks." Thesis, University of British Columbia, 2007. http://hdl.handle.net/2429/31765.
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Cooperative networks exploit the broadcast nature of wireless channels to gain spatial diversity. This dissertation develops two distributed space-time coding schemes for frequency-nonselective channels, and extends and optimizes the previously proposed distributed space-time filtering scheme for frequency-selective channels. Unlike many other distributed space-time coding schemes in the literature, the decentralized schemes proposed in this thesis are designed specifically for wireless networks with a large set of N decode-and-forward relay nodes. At any given time, an a priori unknown subset of nodes acts as relays to cooperatively assist the communication between the source and destination node. To facilitate the cooperation, each physically distributed single--antenna node in the network is assigned a signature vector (signature matrix for multiple-antenna nodes) or signature filter vector. We show that the proposed schemes guarantee a certain diversity gain regardless of which relay nodes in the network cooperate. In addition, the decoding complexity of the various schemes is independent of N and the (random) number of active nodes, and receiver designs advocated originally for traditional co-located antenna systems can be applied. The first scheme is called distributed space-time block coding. Depending on the chosen design, it allows for low-complexity coherent, differential, and noncoherent detection. The second scheme is referred to as distributed space time trellis coding. We show that distributed space-time trellis coding inherits the coding gain of space-time trellis codes over space-time block codes even in the cooperative setting. The two aforementioned schemes are designed for frequency-nonselective fading channels. Finally, we optimize and extend distributed space-time filtering, proposed originally by El Gamal and Aktas, to frequency-selective fading channels. For each scheme, the design criteria are derived. Then, using mathematical tools and classical optimization techniques, efficient methods for the design of the set of signature vectors, signature matrices, and signature filter vectors are provided. Furthermore, the achievable diversity gain, as well as the loss entailed by the distributed implementation of each scheme, are characterized and verified via simulations. Finally, we apply noncoherent distributed space-time block coding to a practical wireless sensor network and show that the proposed scheme is a promising solution for cooperative communication in future sensor, ad hoc, and wireless networks.Applied Science, Faculty of
Electrical and Computer Engineering, Department of
Graduate
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Nguyen, Anh Van. "Concatenated space-time coding for wireless systems." Diss., Georgia Institute of Technology, 2002. http://hdl.handle.net/1853/13533.
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Masoud, Masoud. "Space-time block coding for wireless communications." Thesis, University of Hertfordshire, 2008. http://hdl.handle.net/2299/2548.
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Wireless designers constantly seek to improve the spectrum efficiency/capacity, coverage of wireless networks, and link reliability. Space-time wireless technology that uses multiple antennas along with appropriate signalling and receiver techniques offers a powerful tool for improving wireless performance. Some aspects of this technology have already been incorporated into various wireless network and cellular mobile standards. More advanced MIMO techniques are planned for future mobile networks, wireless local area network (LANs) and wide area network (WANs). Multiple antennas when used with appropriate space-time coding (STC) techniques can achieve huge performance gains in multipath fading wireless links. The fundamentals of space-time coding were established in the context of space-time Trellis coding by Tarokh, Seshadri and Calderbank. Alamouti then proposed a simple transmit diversity coding scheme and based on this scheme, general space-time block codes were further introduced by Tarokh, Jafarkhani and Calderbank. Since then space-time coding has soon evolved into a most vibrant research area in wireless communications. Recently, space-time block coding has been adopted in the third generation mobile communication standard which aims to deliver true multimedia capability. Space-time block codes have a most attractive feature of the linear decoding/detection algorithms and thus become the most popular among different STC techniques. The decoding of space-time block codes, however, requires knowledge of channels at the receiver and in most publications, channel parameters are assumed known, which is not practical due to the changing channel conditions in real communication systems. This thesis is mainly concerned with space-time block codes and their performances. The focus is on signal detection and channel estimation for wireless communication systems using space-time block codes. We first present the required background materials, discuss different implementations of space-time block codes using different numbers of transmit and receive antennas, and evaluate the performances of space-time block codes using binary phase-shift keying (BPSK), quadrature phase-shift keying (QPSK), and quadrature amplitude modulation (QAM). Then, we investigate Tarokh’s joint detection scheme with no channel state information thoroughly, and also propose a new general joint channel estimation and data detection scheme that works with QPSK and 16-QAM and different numbers of antennas. Next, we further study Yang’s channel estimation scheme, and expand this channel estimation scheme to work with 16-QAM modulation. After dealing with complex signal constellations, we subsequently develop the equations and algorithms of both channel estimation schemes to further test their performances when real signals are used (BPSK modulation). Then, we simulate and compare the performances of the two new channel estimation schemes when employing different number of transmit and receive antennas and when employing different modulation methods. Finally, conclusions are drawn and further research areas are discussed.
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Song, Lingyang. "Differential space-time coding techniques and MIMO." Thesis, University of York, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.434157.
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Wang, Jibing, Kung Yao, and Don Whiteman. "Space-Time Coding for Avionic Telemetry Channels." International Foundation for Telemetering, 2003. http://hdl.handle.net/10150/607482.
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International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, NevadaMultiple antennas promise high data capacity for wireless communications. Most space-time coding schemes in literature focus on the rich scatter environment. In this paper, we argue that minimax criterion is a good design criterion for space-time codes over the avionic telemetry channels. This design criterion is different than those of space-time codes over rich scattering Rayleigh fading channels. Theoretical and numerical results show that the codes with optimal performance in Rayleigh fading channels do not necessarily have optimal performance in avionic telemetry channels. Therefore, the space-time codes should be carefully designed/selected when used in the avionic telemetry channels.
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Zajic, Alenka. "Space-time channel modeling, simulation, and coding." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/26569.
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Thesis (Ph.D)--Electrical and Computer Engineering, Georgia Institute of Technology, 2009.Committee Chair: Stuber,Gordon L.; Committee Member: Durgin, Gregory D.; Committee Member: Kim, Hyesoon; Committee Member: Li, Ye (Geoffrey); Committee Member: McLaughlin, Steven W.; Committee Member: Riley, George F.. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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Van, Wyk Daniel Jacobus. "Space-time turbo coding for CDMA mobile communications." Pretoria : [s.n.], 2000. http://upetd.up.ac.za/thesis/available/etd-01172007-112643/.
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Granados, Omar D. "Space-Time Coding for Polynomial Phase Modulated Signals." FIU Digital Commons, 2011. http://digitalcommons.fiu.edu/etd/378.
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Polynomial phase modulated (PPM) signals have been shown to provide improved error rate performance with respect to conventional modulation formats under additive white Gaussian noise and fading channels in single-input single-output (SISO) communication systems. In this dissertation, systems with two and four transmit antennas using PPM signals were presented. In both cases we employed full-rate space-time block codes in order to take advantage of the multipath channel. For two transmit antennas, we used the orthogonal space-time block code (OSTBC) proposed by Alamouti and performed symbol-wise decoding by estimating the phase coefficients of the PPM signal using three different methods: maximum-likelihood (ML), sub-optimal ML (S-ML) and the high-order ambiguity function (HAF). In the case of four transmit antennas, we used the full-rate quasi-OSTBC (QOSTBC) proposed by Jafarkhani. However, in order to ensure the best error rate performance, PPM signals were selected such as to maximize the QOSTBC’s minimum coding gain distance (CGD). Since this method does not always provide a unique solution, an additional criterion known as maximum channel interference coefficient (CIC) was proposed. Through Monte Carlo simulations it was shown that by using QOSTBCs along with the properly selected PPM constellations based on the CGD and CIC criteria, full diversity in flat fading channels and thus, low BER at high signal-to-noise ratios (SNR) can be ensured. Lastly, the performance of symbol-wise decoding for QOSTBCs was evaluated. In this case a quasi zero-forcing method was used to decouple the received signal and it was shown that although this technique reduces the decoding complexity of the system, there is a penalty to be paid in terms of error rate performance at high SNRs.
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Hong, Zhihong. "Robust Coding Methods For Space-Time Wireless Communications." NCSU, 2002. http://www.lib.ncsu.edu/theses/available/etd-20020117-144929.
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HONG, ZHIHONG. Robust Coding Methods For Space-Time Wireless Communications. (Under the direction of Dr. Brian L. Hughes.)Space-time coding can exploit the presence of multiple transmit and receive antennasto increase diversity, spectral efficiency, and received power, to improvethe performance in wireless communication systems. Thus far, most work on space-time coding has assumed highly idealized channel fading conditions (e.g., quasi-static or ideal fast fading)as well as perfect channel state information at the receiver. Both of these assumptionsare often questionable in practice. In this dissertation, we present a new and general coding architecture for multi-antennacommunications, which is designed to perform well under a wide variety of channel fading conditionsand which (when differentially encoded) does not require accurate channel estimatesat the receiver. The architecture combines serial concatenation of short, full-diversityspace-time block codes with bit-interleaved coded modulation. Under slow fadingconditions, we show that codes constructed in this way achieve full diversity and perform close to the best known space-time trellis codes of comparable complexity. Under fast fading conditions, we show that these same codes can achieve higher diversity than all previously knowncodes of the same complexity. When used with differential space-time modulation, thesecodes can be reliably detected with or without channel estimates at the transmitter or receiver. Moreover, when iterative decoding is applied, the performance of these codes couldbe further improved.
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Ismail, Amr. "Low Complexity Space-Time coding for MIMO systems." Phd thesis, Supélec, 2011. http://tel.archives-ouvertes.fr/tel-00771982.
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The last few years witnessed a dramatic increase in the demand on high-rate reliable wireless communications. In order to meet these new requirements, resorting to Multiple-Input Multiple-Output (MIMO) techniques was inevitable as they may offer high-rate reliable wireless communications without any additional bandwidth. In the case where the transmitter does not have any prior knowledge about the channel state information, space-time coding techniques have proved to efficiently exploit the MIMO channel degrees of freedom while taking advantage of the maximum diversity gain. On the other hand, the ML decoding complexity of Space-Time Codes (STCs) generally increases exponentially with the rate which imposes an important challenge to their incorporation in recent communications standards. Recognizing the importance of the low-complexity criterion in the STC design for practical considerations, this thesis focuses on the design of new low-complexity Space-Time Block Codes (STBCs) where the transmitted code matrix can be expressed as a weighted linear combination of information symbols and we propose new codes that are decoded with a lower complexity than that of their rivals in the literature while providing better or slightly lower performance.
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Passas, Georgios. "Effient VLSI Architectures for Space-Time Coding Algorithms." Thesis, University of Leeds, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.502924.
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Baker, Dirk A. "Space-time block coding with imperfect channel estimates." Morgantown, W. Va. : [West Virginia University Libraries], 2001. http://etd.wvu.edu/templates/showETD.cfm?recnum=1843.
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Thesis (M.S.)--West Virginia University, 2001.Title from document title page. Document formatted into pages; contains iv, 74 p. : ill. Includes abstract. Includes bibliographical references (p. 73-74).
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Wong, Wing Hin. "Nonuniform space-time codes for layered source coding." [Gainesville, Fla.] : University of Florida, 2003. http://purl.fcla.edu/fcla/etd/UFE0000826.
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Ding, Zhiguo. "Receiver algorithm design for space time block coding systems." Thesis, Imperial College London, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.420523.
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Bendoukha, Samir. "Blind equalisation for space-time coding over ISI channels." Thesis, University of Strathclyde, 2010. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=14451.
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Nelson, Tom. "ALAMOUTI SPACE-TIME CODING FOR QPSK WITH DELAY DIFFERENTIAL." International Foundation for Telemetering, 2003. http://hdl.handle.net/10150/607483.
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International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, NevadaSpace-time coding (STC) for QPSK where the transmitted signals are received with the same delay is well known. This paper examines the case where the transmitted signals are received with a nonnegligible delay differential when the Alamouti 2x1 STC is used. Such a differential can be caused by a large spacing of the transmit antennas. In this paper, an expression for the received signal with a delay differential is derived and a decoding algorithm for that signal is developed. In addition, the performance of this new algorithm is compared to the standard Alamouti decoding algorithm for various delay differentials.
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Liu, Youjian. "An algebraic space-time coding theory and its applications /." The Ohio State University, 2001. http://rave.ohiolink.edu/etdc/view?acc_num=osu1488204276534358.
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Taban, Alper Altınkaya Mustafa Aziz. "Space-time coding for CDMA-based wireless communication systems/." [s.l.]: [s.n.], 2002. http://library.iyte.edu.tr/tezler/master/elektrikveelektronikmuh/T000134.pdf.
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Karimdady, Sharifabad Farnaz. "Covariance Modeling and Space-Time Coding for MIMO systems." BYU ScholarsArchive, 2013. https://scholarsarchive.byu.edu/etd/3510.
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The full spatial covariance matrix of the multiple input multiple-output (MIMO) channel is an important quantity in channel modeling, communication system signal processing, and performance analysis, and therefore this matrix forms the heart of the research outlined in this dissertation. The work begins with an investigation of a generalized framework for computing the full MIMO spatial covariance based on the power angular spectrum (PAS) of the multipath field and the transmit and receive antenna element radiation patterns. For the case of uniform linear arrays and when the PAS clusters satisfy uniform, truncated Gaussian, or truncated Laplacian distributions, a series expansion is used to allow analytic evaluation of the required integrals in the formulation. The study also demonstrates the validity of some simplifying assumptions used to reduce the complexity of the covariance computation by applying the technique to ray tracing data as well as considers an analysis of the convergence properties of the series when computed using a finite number of terms. The insights and tools obtained from this covariance analysis are then used to develop a general approach for constructing MIMO transmit and receive beamforming vectors based on the full spatial covariance. While transmit and receive beamforming for the MIMO channel is a well-studied topic, when the transmit precoding is based on channel covariance information, developing near-optimal transmit and receive beamformers when the receiver is constrained to use linear processing remains an unsolved problem. This iterative beamforming algorithm presented here can accommodate different types of available channel information and receiver capabilities as well as either a sum power constraint or a per-antenna power constraint. While the latter is more realistic, construction of the optimal transmit precoder is less understood for this constraint. Simulation results based on measured channels demonstrate that the approach generates beamformer solutions whose performance rivals that achieved for an optimal nonlinear receiver architecture.
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Vilaipornsawai, Usa. "Space-time coding and receiver design for unknown time-varying wireless channels." Thesis, McGill University, 2009. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=66767.
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This thesis considers a joint channel estimation and data detection algorithm for Multiple Space-Time Trellis Codes (MSTTCs) over high Doppler fading channels. This algorithm belongs to the Per-Survivor Processing (PSP) family, where a survivor associated with a trellis state is used for channel estimation. We propose a smoothed data detection technique to increase the probability of the survivor being a correct data sequence. A symbol by symbol Maximum A Posteriori Probability (MAP) criterion, with a fixed delay $D$, is employed for data detection, combined with a Kalman Predictor (KP) for channel estimation. This novel algorithm, called Smoothed Data Detection and Kalman Estimation (SDD-KE), provides a significant performance gain when $D>0$ over $D=0$, with a linear increase in complexity when $D$ increases. Comparison with the Delayed Mixture Kalman Filtering (DMKF) technique shows that the SDD-KE algor ithm provides important performance and complexity advantages. Motivated by the fact that all joint channel estimation and data detection schemes suffer from the phase ambiguity problem, we developed a design method that can transform any phase ambiguity prone STTC into a Phase Ambiguity Diminishing STTC (PAD-STTC). A PAD-STTC can be considered as an MSTTC with special constellation mappings. The design criteria for these mappings are developed by trading among the PAD property, diversity, and coding gain. Two PAD-STTC structures termed PAD1-STTC and PAD2-STTC are proposed, where PAD2-STTC increases the number of states over the constituent STTC. Computer simulation results indicate that PAD-STTCs can solve the phase ambiguity problem and provide a larger diversity gain than the constituent STTC over high Doppler fading channels. Moreover, with the same constituent STTC, the PAD2-STTC outperforms the PAD1-STTC at the expense of increased complexity. This thesis also develops a joint channel estimationCette thése présente une méthode conjointe d'estimation de voie et de détection de données pour les codes multiples espace-temps en treillis (MSTTCs) sur des canauxà évanouissement avec gros effet Doppler. Cette méthode se base sur le principe du "traitement par survivant" (PSP), oùà chaque état du treillis, le chemin survivant est utilisé pour l'estimation de voie. Nous proposons une technique de détection de données lissées pour augmenter la probabilité que le survivant correspondeà la bonne séquence de données. Le processus de détection utilise le critére du maximum de probabilitéà posteriori (MAP) symbole par symbole avec un délai fixe $D$, tandis que le processus d'estimation se base sur un prédicteur de Kalman. Ce nouvel algorithme est appelé Détection de Données Lissées et Estimation Kalman (SDD-KE). Pour $D>0$, des gains significatifs sont obtenus comparativementà $D=0$, et la complexité de l'algorithme augmente linéairement avec $D$. D'autre part, comparéà la technique du Delayed Mixture Kalman Filter (DMKF), notre approche permet d'importantes améliorations en terme de performance et de complexité.Motivés par le fait que le probléme d'ambiguité sur les phases est communà toute méthode conjointe d'estimation de voie et de détection de données, nous avons developpé une méthode de conception capable de transformer n'importe quel STTC en un nouvel STTC Réduisant l'Ambiguité sur les Phases (PAD-STTC). Un PAD-STTC est en fait un MSTTC avec des mappages de constellation particuliers. Les critéres de conception de ces mappages sont obtenues en tenant compte de la réduction du probléme d'ambiguité sur les phases ainsi que des gains de diversité et de codage. Deux structures PAD-STTCs nommées PAD1-STTC et PAD2-STTC sont proposées, avec la distinction que PAD2-STTC utilise un plus grand nombre d'états que le STTC corresponda
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Maw, Rachel Leigh. "Space-time Coded Systems with Continuous Phase Modulation." Thesis, University of Canterbury. Electrical and Computer Engineering, 2007. http://hdl.handle.net/10092/1185.
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Space-time coded systems developed in the last ten years have been designed primarily using linear modulation. Non-linear continuous phase modulation has desirable constant envelope properties and considerable potential in space-time coded systems. The work in this thesis is focussed on developing and analysing an integrated space-time coded continuous phase modulated (STC-CPM) system. The coding of the space-time encoder and the modulation is incorporated into a single trellis encoder. This allows state combining, which leads to complexity reduction due to the reduced number of states. Design criteria for STC-CPM are summarized and the Euclidean distance is shown to be important for code design. The integrated STC-CPM system design enables systematic spacetime code searches that find optimal space-time codes, to be easily implemented. Optimal rate-1/2 and rate-2/3 space-time codes are found by maximizing the system's minimum squared Euclidean distance. These codes can provide high throughput and good coding gains over un-optimized full rank codes, such as delay diversity, in a quasi-static flat fading environment. Performance bounds are developed using a union bound argument and the pairwise error probability. Approximations of the bounds are evaluated. These truncated upper bounds predict the slopes of the simulated performance curves at low error rates.
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Gärtner, Markus Eduard. "Space-time coding and multiple access in MIMO fading channels /." Zürich : ETH, 2007. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=17414.
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Gregoratti, David. "Randomized space-time block coding for the multiple-relay channel." Doctoral thesis, Universitat Politècnica de Catalunya, 2010. http://hdl.handle.net/10803/6949.
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En la última década, la cooperación entre usuarios ha generado un gran interés por la posibilidad de mejorar la velocidad de transmisión en las redes de comunicaciones inalámbricas. El objetivo es formar un array con las antenas de todos los dispositivos y, de esta forma, aplicar técnicas de procesado espacio-temporal. El esquema de cooperación más sencillo es el canal con relays: todos los terminales que escuchen una comunicación entre dos puntos pueden ayudar a la fuente retransmitiendo lo que hayan recibido.En un sistema realista, los relays no disponen de información sobre el canal en trasmisión. En este escenario, los códigos espacio-temporales (STC, del inglés space-time coding) son la alternativa más eficiente para aprovechar la diversidad introducida por los relays. Sin embargo, los STC clásicos están diseñados para un número limitado y fijo de antenas transmisoras y no se adaptan bien a sistemas cooperativos donde el número de relays puede ser elevado y, sobretodo, puede variar en el tiempo, según los usuarios entren o salgan de la red. El problema principal es la necesidad de usar un código nuevo cada vez que cambie la configuración de la red, generando un importante tráfico de señalización.
Esta tesis analiza un código espacio-temporal a bloques de dispersión lineal (LD-STBC, del inglés linear-dispersion space-time block coding), aleatorio y distribuido: a cada relay se le asigna una matriz aleatoria que aplica una transformación lineal al vector que contiene los símbolos de la fuente. Cada matriz se genera de forma independiente y sin ninguna relación con el número de usuarios involucrados. De esta manera, el número de nodos puede variar sin necesidad de modificar los códigos existentes.
La forma más intuitiva de construir matrices de dispersión lineal independientes es que sus elementos sean variables aleatorias independientes e idénticamente distribuidas (i.i.d.). Por esta razón, se estudia primero la eficiencia espectral obtenida por este tipo de LD-STBC. Es importante remarcar que la eficiencia espectral es una cantidad aleatoria, ya que es una función de los códigos aleatorios anteriormente descritos. Sin embargo, cuando las dimensiones de las matrices crecen infinitamente pero manteniendo constante la tasa del código (relación entre número de símbolos de la fuente sobre el número de símbolos de los relays), la eficiencia espectral converge rápidamente hacia una cantidad determinista. Este resultado se demuestra usando la teoría de las matrices aleatorias. Por esta razón, el sistema se analiza aproximando la eficiencia espectral con su limite. Por ejemplo, la comparación con el canal directo entre fuente y destino permite definir unas condiciones suficientes en donde el sistema con relays es superior a la comunicación punto a punto.
Posteriormente se debe analizar la probabilidad de outage, es decir la probabilidad de que, debido a la baja calidad del canal, la eficiencia espectral sea menor que la velocidad de transmisión solicitada por el sistema. Como ya se ha mencionado anteriormente, los relays se introducen para aumentar la diversidad del canal y, con ella, el número de caminos independientes entre la fuente y el receptor, reduciendo la probabilidad de outage. Para los LD-STBC i.i.d. las prestaciones en términos de outage dependen del tipo de relay (amplify and forward o decode and forward) y son función de la tasa del código, que debe ser cuidadosamente elegida para maximizar el orden de diversidad sin desperdiciar demasiados recursos.
Finalmente, en el último capítulo de la tesis se considera otro tipo de LD-STBC, distinto del i.i.d. analizado hasta ahora. En este caso, las matrices de dispersión lineal siguen siendo independientes la una de la otra pero se añade la restricción de que cada una tenga columnas (o filas, según la tasa del código) ortogonales. Así, se consigue que el código siga siendo flexible con respecto a las variaciones en el número de usuarios, pero su estructura permite reducir la interferencia generada por cada relay, como se puede notar comparando su eficiencia espectral con la eficiencia espectral obtenida por el código i.i.d. Cabe destacar que el análisis asintótico de estos códigos (llamados isométricos) se basa en herramientas matemáticas más sofisticadas que las anteriores y, por lo tanto, es necesario un estudio más profundo para poder entender cómo se comporta en términos de outage.
In the last decade, cooperation among multiple terminals has been seen as one of the more promising strategies to improve transmission speed in wireless communications networks. Basically, the idea is to mimic an antenna array and apply distributed versions of well-known space-diversity techniques. In this context, the simplest cooperative scheme is the relay channel: all the terminals (relays) that overhear a point-to-point communication between a source and a destination may decide to aid the source by forwarding (relaying) its message.
In a mobile system, it is common to assume that the relays do not have any information about the channel between them and the destination. Under this hypothesis, the best solution to exploit the diversity offered by multiple transmitting antennas is to use space-time coding (STC). However, classical STC's are designed for systems with a fixed and usually low number of antennas. Thus, they are not suitable for relaying in most mobile communications systems where the number of terminals is potentially large and may vary as users join or leave the network. For each new configuration, a new code has to be chosen and notified to the relays, introducing a set-up overhead of signaling traffic.
In this dissertation we will propose and analyze a randomized distributed linear-dispersion space-time block code (LD-STBC): each relay is assigned a specific matrix which linearly transforms (left-multiplies) the column vector of source symbols. Each matrix is independently generated and does not depend on the total number of transmitters, which can thus change without interrupting data transmission for a new code--relay assignment.
The more intuitive way to build independent linear-dispersion matrices is to fill them with independent and identically distributed (i.i.d.) random variables. Therefore, we will first consider these i.i.d. codes and characterize the resulting spectral efficiency. In order to analyze the performance achieved by the system, we consider a large-system analysis based on random matrix theory. We will show that the random spectral efficiency (function of the random linear-dispersion matrices) converges almost surely to a deterministic quantity when the dimensions of the code grow indefinitely while keeping constant the coding rate. Since convergence is very fast, the random spectral efficiency will be approximated by the deterministic limit in the subsequent analysis. By comparison with the direct link, sufficient conditions are derived for the superiority of relaying.
Next, we will analyze the outage probability of the system, that is the probability that the spectral efficiency falls below a given target rate due to channel fading. The main purpose of diversity techniques is to introduce alternative paths from the source to the destination, so that data transmission does not fail when the direct link undergoes deep fading. We will show that the diversity behavior of LD-STBC relaying mainly depends on both the coding rate and the relaying strategy (amplify and forward or decode and forward). It is then important to choose the coding rate that maximizes the diversity order without wasting too many resources.
To conclude the dissertation, we will consider a different code based on independent isometric Haar-distributed random linear-dispersion matrices. The
new code maintains the flexibility of the previous one with respect to variations in the number of relays. However, the more complex structure of the codes allows a noticeable reduction of the interference generated by the relays. Unfortunately, isometric codes also require more sophisticated mathematical tools for their asymptotic analysis. For this reason, we simply introduce the problem by showing that it is possible to have some spectral-efficiency gain with respect to i.i.d. codes. The outage-probability analysis requires a more thorough understanding and will be the subject of future work.
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Fu, Shengli. "Space-time coding and decoding for MIMO wireless communication systems." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file 0.57Mb, 156 p, 2005. http://wwwlib.umi.com/dissertations/fullcit?3182631.
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Elazreg, A. M. "Distributed space time block coding in asynchronous cooperative relay networks." Thesis, Loughborough University, 2013. https://dspace.lboro.ac.uk/2134/12032.
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The design and analysis of various distributed space time block coding schemes for asynchronous cooperative relay networks is considered in this thesis. Rayleigh frequency flat fading channels are assumed to model the links in the networks, and interference suppression techniques together with an orthogonal frequency division multiplexing type transmission approach are employed to mitigate the synchronization errors at the destination node induced by the different delays through the relay nodes. Closed-loop space time block coding is first considered in the context of decode-and-forward (regenerative) networks. In particular, quasi orthogonal and extended orthogonal coding techniques are employed for transmission from four relay nodes and parallel interference cancellation detection is exploited to mitigate synchronization errors. Availability of a direct link between the source and destination nodes is studied, and a new Alamouti space time block coding technique with parallel interference cancellation detection which does not require such a direct link connection and employs two relay nodes is proposed. Outer coding is then added to gain further improvement in end-to-end performance and amplify-and-forward (non regenerative) type networks together with distributed space time coding are considered to reduce relay node complexity. Novel detection schemes are then proposed for decode-and-forward networks with closed-loop extended orthogonal coding which reduce the computational complexity of the parallel interference cancellation. Both sub-optimum and near-optimum detectors are presented for relay nodes with single or dual antennas. End-to-end bit error rate simulations confirm the potential of the approaches and their ability to mitigate synchronization errors. A relay selection approach is also formulated which maximizes spatial diversity gain and attains robustness to timing errors. Finally, a new closed-loop distributed extended orthogonal space time block coding solution for amplify-and-forward type networks which minimizes the number of feedback bits by using a cyclic rotation phase is presented. This approach utilizes an orthogonal frequency division multiplexing type transmission structure with a cyclic prefix to mitigate synchronization errors. End-to-end bit error performance evaluations verify the efficacy of the scheme and its success in overcoming synchronization errors.
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Geoghegan, Mark, and Louis Boucher. "Space-Time Coding Solution to the Two-Antenna Interference Problem." International Foundation for Telemetering, 2014. http://hdl.handle.net/10150/577388.
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ITC/USA 2014 Conference Proceedings / The Fiftieth Annual International Telemetering Conference and Technical Exhibition / October 20-23, 2014 / Town and Country Resort & Convention Center, San Diego, CAIn order to provide reliable line-of-sight communications, test aircraft typically use two transmit antennas to create top and bottom hemispherical patterns that cover the full range of possible aircraft orientations. The two transmit signals are normally generated by a single transmitter with the power being split between the two antennas. Although this configuration is straightforward and easy to implement, problems can arise due to the two signals constructively and destructively interfering with each other. This can result in the composite antenna pattern having periodic nulls with a depth and geometric spacing dependent upon the amplitude and phase differences of the two transmitted signals. This problem is usually addressed by either unevenly splitting the transmit power between the two antennas, or by using two separate transmitters at different frequencies. Unfortunately, these methods have drawbacks that require either system performance or cost trade-offs. This paper discusses the use of Space-Time Coding to eliminate this antenna interaction by transmitting modified waveforms that simultaneously allow for both full power transmission and single-channel operation. This approach effectively restores the nominal antenna performance, thereby resulting in better overall coverage and less pattern-induced dropouts. Telemetry performance results from recent flight testing are presented to validate the benefits of this approach.
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Rice, Michael. "Space-Time Coding for Aeronautical Telemetry: Part I - System Description." International Foundation for Telemetering, 2011. http://hdl.handle.net/10150/595758.
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ITC/USA 2011 Conference Proceedings / The Forty-Seventh Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2011 / Bally's Las Vegas, Las Vegas, NevadaThis paper described the design and implementation of a prototype transmitter and a prototype demodulator/decoder for space-time coded SOQPSK-TG for aeronautical telemetry. The design exercise showed that the space-time coding concept can be reduced to hardware. The laboratory bit error rate tests showed that the performance of the prototype demodulator in a 2-transmit/1-receive antenna configuration is comparable to that of existing SOQPSK demodulators in a 1-transmit/1- receive antenna configuration.
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Rice, Michael, and Kip Temple. "Space-Time Coding for Aeronautical Telemetry: Part II - Experimental Results." International Foundation for Telemetering, 2011. http://hdl.handle.net/10150/595778.
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ITC/USA 2011 Conference Proceedings / The Forty-Seventh Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2011 / Bally's Las Vegas, Las Vegas, NevadaExperiments involving side-by-side comparisons of traditional two-antenna transmissions and space-time coded (STC) transmissions involving two transmit antennas confirm theoretical predictions that space time coding is effective in removing signal dropouts caused by the "twoantenna problem." The experiments involved real transmitters on an airborne platform and a prototype demodulator operating at the Air Force Flight Test Center. The theory is confirmed both by the behaviors of the received signal powers from the two signaling approaches as well as the improved link availability based on the bit error rate performance.
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Tujkovic, D. (Djordje). "Space-time turbo coded modulation for wireless communication systems." Doctoral thesis, University of Oulu, 2003. http://urn.fi/urn:isbn:9514269977.
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Abstract
High computational complexity constrains truly exhaustive computer searches for good space-time (ST) coded modulations mostly to low constraint length space-time trellis codes (STTrCs). Such codes are primarily devised to achieve maximum transmit diversity gain. Due to their low memory order, optimization based on the design criterion of secondary importance typically results in rather modest coding gains. As another disadvantage of limited freedom, the different low memory order STTrCs are almost exclusively constructed for either slow or fast fading channels. Therefore in practical applications characterized by extremely variable Doppler frequencies, the codes typically fail to demonstrate desired robustness. On the other hand, the main drawback of eventually increased constraint lengths is the prohibitively large decoding complexity, which may increase exponentially if optimal maximum-likelihood decoding (MLD) is applied at the receiver. Therefore, robust ST coded modulation schemes with large equivalent memory orders structured as to allow sub-optimal, low complexity, iterative decoding are needed.
To address the aforementioned issues, this thesis proposes parallel concatenated space-time turbo coded modulation (STTuCM). It is among the earliest multiple-input multiple-output (MIMO) coded modulation designs built on the intersection of ST coding and turbo coding. The systematic procedure for building an equivalent recursive STTrC (Rec-STTrC) based on the trellis diagram of an arbitrary non-recursive STTrC is first introduced. The parallel concatenation of punctured constituent Rec-STTrCs designed upon the non-recursive Tarokh et al. STTrCs (Tarokh-STTrCs) is evaluated under different narrow-band frequency flat block fading channels. Combined with novel transceiver designs, the applications for future wide-band code division multiple access (WCDMA) and orthogonal frequency division multiplexing (OFDM) based broadband radio communication systems are considered. The distance spectrum (DS) interpretation of the STTuCM and union bound (UB) performance analysis over slow and fast fading channels reveal the importance of multiplicities in the ST coding design. The modified design criteria for space-time codes (STCs) are introduced that capture the joint effects of error coefficients and multiplicities in the two dimensional DS of a code. Applied to STTuCM, such DS optimization resulted in a new set of constituent codes (CCs) for improved and robust performance over both slow and fast fading channels. A recursive systematic form with a primitive equivalent feedback polynomial is assumed for CCs to assure good convergence in iterative decoding. To justify such assumptions, the iterative decoding convergence analysis based on the Gaussian approximation of the extrinsic information is performed. The DS interpretation, introduced with respect to an arbitrary defined effective Hamming distance (EHD) and effective product distance (EPD), is applicable to the general class of geometrically non-uniform (GNU) CCs. With no constrains on the implemented information interleaving, the STTuCM constructed from newly designed CCs achieves full spatial diversity over quasi-static fading channels, the condition commonly identified as the most restrictive for robust performance over a variety of Doppler spreads. Finally, the impact of bit-wise and symbol-wise information interleaving on the performance of STTuCM is studied.
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Chu, Li Electrical Engineering & Telecommunications Faculty of Engineering UNSW. "Space-time coded transmission schemes on wireless channels." Awarded by:University of New South Wales. Electrical Engineering & Telecommunications, 2007. http://handle.unsw.edu.au/1959.4/40880.
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Highly reliable and fast wireless communication services demand the communication channel capacity to be fully exploited. Vast amount of research effort have been expanded in the development of advance technologies, such as signal processing, channel coding, modulation/demodulation, diversity techniques, and so on. This thesis focuses on the development of space-time coded transmission schemes. In order to provide high diversity gain with minimum design complexity, we propose a closed-loop beamforming transmission technology combined with existing simple channel coding method. We show that this coded beamforming scheme can achieve full diversity as the space-time coding technique does for a multiple-antenna system, while significantly reducing the design complexity. It is normally impractical to install multiple antennas on a small wireless communication device. We therefore further our research to cooperative communication, in which single-antenna communicators share their antennas with partners in information relay, so that the benefit of multiple-antenna transmission can be achieved for the singleantenna users. We analyze the system performance for the typical decode-and-forward user cooperative system, formulate the code design criteria, and construct optimal codes. To simplify the system design, we introduce estimate-and-forward protocol with differential modulation scheme. In order to ensure the practicality of the system design, we introduce an equivalent link model to replace the source-relay-destination link, taking into account the imperfect detections at the relay. Finally we extend the analysis to a multiple-relay system using selective combiner at the destination.
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Lin, Rui. "Hybrid ARQ Schemes for Non-orthogonal Space-time Block Codes." Thesis, University of Canterbury. Electrical and Computer Engineering, 2007. http://hdl.handle.net/10092/1183.
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Automatic Repeat-reQuest (ARQ) schemes are extensively used in communication systems and computer networks to achieve reliable transmission. Using space-time codes (STCs) with multiple input multiple output (MIMO) or multiple input single output (MISO) systems is an effective way to combat multipath fading, which is the most severe impairment for wireless communication systems. STCs are designed to use the rich scattering multipath environment provided by using multiple transmit antennas. The work done in this thesis focuses on the use of ARQ schemes with non-orthogonal space-time block codes (NOSTBCs) based on Reed Solomon codes. The truncated-selective ARQ (TS-ARQ) scheme is considered and three novel hybrid ARQ (HARQ) schemes are proposed. Simulation results reveal that, compared to using TS-ARQ with orthogonal space-time block codes (OSTBCs), using NOSTBCs with any of the three proposed HARQ schemes can provide significant gains in terms of dropped packet rate and spectral efficiency at the cost of increased decoding complexity. The performance can be further improved by using the water filling principle to adaptively allocate transmit power among transmit antennas.
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Wan, Derrick Che-Yu. "Performance of cooperative space time coding with spatially correlated fading and imperfect channel estimation." Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/907.
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A performance evaluation of CSTC (Cooperative Space Time Coding) with spatially cor-related fading and imperfect channel estimation in Gaussian as well as impulsive noise is presented. Closed form expressions for the pairwise error probability conditioned on the estimated channel gains are derived by assuming the components of the received vector are independent given the estimated channel gains. An expurgated union bound using the limiting before averaging technique given the estimated channel gains is then obtained. Although this assumption is not strictly valid, simulation results show that the bound is accurate in estimating the diversity order as long the channel estimation is not very poor. It is found that CSTC with block fading channels can reduce the frame error rate (FER) relative to SUSTC (Single User Space Time Coding) with quasi-static fading channels, even when the channel gains for each user are strongly correlated and when the channel estimations are very poor.
A decision metric for CSTC with spatially correlated fading, imperfect channel estimation, and impulsive mixture Gaussian noise is derived which yields lower FERs than the Gaussian noise decision metric. Simulation results show that the FER performance of CSTC with mixture Gaussian noise outperforms CSTC with Gaussian noise at low SNR. At high SNR, the FER performance of CSTC with Gaussian noise is better than the FER performance of CSTC with mixture Gaussian noise due to the heavy tail of the mixture Gaussian noise.
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Alamri, Osamah R. "Turbo detection of sphere packing modulation aided space-time coding schemes." Thesis, University of Southampton, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.435719.
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Temple, Kip. "Performance Evaluation of Space-Time Coding on an Airborne Test Platform." International Foundation for Telemetering, 2014. http://hdl.handle.net/10150/577446.
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ITC/USA 2014 Conference Proceedings / The Fiftieth Annual International Telemetering Conference and Technical Exhibition / October 20-23, 2014 / Town and Country Resort & Convention Center, San Diego, CATypical airborne test platforms use multiple telemetry transmit antennas in a top and bottom configuration in order to mitigate signal shadowing during maneuvers on high dynamic platforms. While mitigating one problem, this also creates a co-channel interference problem as the same signal, time delayed with differing amplitude, is sent to both antennas. Space-Time Coding (STC) was developed with the intention of mitigating this co-channel interference problem, also known as the "two antenna problem". Lab testing and preliminary flight testing of developmental and pre-production hardware has been completed and documented. This is the first test dedicated to assessing the performance of a production STC system in a real-world test environment. This paper will briefly describe lab testing that preceded the flight testing, describes the airborne and ground station configurations used during the flight test, and provides detailed results of the performance of the space time coded telemetry link as compared against a reference telemetry link.
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Hayes, Matthew. "Distributed quasi-orthogonal space-time coding in wireless cooperative relay networks." Thesis, Loughborough University, 2011. https://dspace.lboro.ac.uk/2134/9923.
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Cooperative diversity provides a new paradigm in robust wireless re- lay networks that leverages Space-Time (ST) processing techniques to combat the effects of fading. Distributing the encoding over multiple relays that potentially observe uncorrelated channels to a destination terminal has demonstrated promising results in extending range, data- rates and transmit power utilization. Specifically, Space Time Block Codes (STBCs) based on orthogonal designs have proven extremely popular at exploiting spatial diversity through simple distributed pro- cessing without channel knowledge at the relaying terminals. This thesis aims at extending further the extensive design and analysis in relay networks based on orthogonal designs in the context of Quasi- Orthogonal Space Time Block Codes (QOSTBCs). The characterization of Quasi-Orthogonal MIMO channels for cooper- ative networks is performed under Ergodic and Non-Ergodic channel conditions. Specific to cooperative diversity, the sub-channels are as- sumed to observe different shadowing conditions as opposed to the traditional co-located communication system. Under Ergodic chan- nel assumptions novel closed-form solutions for cooperative channel capacity under the constraint of distributed-QOSTBC processing are presented. This analysis is extended to yield closed-form approx- imate expressions and their utility is verified through simulations. The effective use of partial feedback to orthogonalize the QOSTBC is examined and significant gains under specific channel conditions are demonstrated. Distributed systems cooperating over the network introduce chal- lenges in synchronization. Without extensive network management it is difficult to synchronize all the nodes participating in the relaying between source and destination terminals. Based on QOSTBC tech- niques simple encoding strategies are introduced that provide compa- rable throughput to schemes under synchronous conditions with neg- ligible overhead in processing throughout the protocol. Both mutli- carrier and single-carrier schemes are developed to enable the flexi- bility to limit Peak-to-Average-Power-Ratio (PAPR) and reduce the Radio Frequency (RF) requirements of the relaying terminals. The insights gained in asynchronous design in flat-fading cooperative channels are then extended to broadband networks over frequency- selective channels where the novel application of QOSTBCs are used in distributed-Space-Time-Frequency (STF) coding. Specifically, cod- ing schemes are presented that extract both spatial and mutli-path diversity offered by the cooperative Multiple-Input Multiple-Output (MIMO) channel. To provide maximum flexibility the proposed schemes are adapted to facilitate both Decode-and-Forward (DF) and Amplify- and-Forward (AF) relaying. In-depth Pairwise-Error-Probability (PEP) analysis provides distinct design specifications which tailor the distributed- STF code to maximize the diversity and coding gain offered under the DF and AF protocols. Numerical simulation are used extensively to confirm the validity of the proposed cooperative schemes. The analytical and numerical re- sults demonstrate the effective use of QOSTBC over orthogonal tech- niques in a wide range of channel conditions.
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Nelson, Tom, Michael Rice, and Michael Jensen. "EXPERIMENTAL RESULTS FOR SPACE-TIME CODING USING ARTM TIER-1 MODULATION." International Foundation for Telemetering, 2005. http://hdl.handle.net/10150/604783.
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ITC/USA 2005 Conference Proceedings / The Forty-First Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2005 / Riviera Hotel & Convention Center, Las Vegas, NevadaWhen using two antennas to transmit telemetry from an airborne platform, self interference results when both transmit antennae are visible to the receive antenna. This self interference can lead to link outages and severe distortion, especially as data rates increase above 5 Mbits/sec. Space-time coding can be used to provide transmit diversity to overcome this self interference problem. This paper describes the results of experiments (conducted at Edwards Air Force Base, California, USA) using FQPSK-JR waveforms coded with ARTM Tier-1 Space-Time Block Code.
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Manna, Mustafa A. "Modified quasi-orthogonal space-time block coding in distributed wireless networks." Thesis, Loughborough University, 2015. https://dspace.lboro.ac.uk/2134/16629.
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Cooperative networks have developed as a useful technique that can achieve the same advantage as multi-input and multi-output (MIMO) wireless systems such as spatial diversity, whilst resolving the difficulties of co-located multiple antennas at individual nodes and avoiding the effect of path-loss and shadowing. Spatial diversity in cooperative networks is known as cooperative diversity, and can enhance system reliability without sacrificing the scarce bandwidth resource or consuming more transmit power. It enables single-antenna terminals in a wireless relay network to share their antennas to form a virtual antenna array on the basis of their distributed locations. However, there remain technical challenges to maximize the benefit of cooperative communications, e.g. data rate, asynchronous transmission and outage. In this thesis, therefore, firstly, a modified distributed quasi-orthogonal space-time block coding (M-D-QO-STBC) scheme with increased code gain distance (CGD) for one-way and two-way amplify-and-forward wireless relay networks is proposed. This modified code is designed from set partitioning a larger codebook formed from two quasi-orthogonal space time block codes with different signal rotations then the subcodes are combined and pruned to arrive at the modified codebook with the desired rate in order to increase the CGD. Moreover, for higher rate codes the code distance is maximized by using a genetic algorithm to search for the optimum rotation matrix. This scheme has very good performance and significant coding gain over existing codes such as the open-loop and closed-loop QO-STBC schemes. In addition, the topic of outage probability analysis in the context of multi-relay selection from $N$ available relay nodes for one-way amplify-and-forward cooperative relay networks is considered together with the best relay selection, the $N^{th}$ relay selection and best four relay selection in two-way amplify-and-forward cooperative relay networks. The relay selection is performed either on the basis of a max-min strategy or one based on maximizing exact end-to-end signal-to-noise ratio. Furthermore, in this thesis, robust schemes for cooperative relays based on the M-D-QO-STBC scheme for both one-way and two-way asynchronous cooperative relay networks are considered to overcome the issue of a synchronism in wireless cooperative relay networks. In particular, an orthogonal frequency division multiplexing (OFDM) data structure is employed with cyclic prefix (CP) insertion at the source in the one-way cooperative relay network and at the two terminal nodes in the two-way cooperative network to combat the effects of time asynchronism. As such, this technique can effectively cope with the effects of timing errors. Finally, outage probability performance of a proposed amplify-and-forward cooperative cognitive relay network is evaluated and the cognitive relays are assumed to exploit an overlay approach. A closed form expression for the outage probability for multi-relay selection cooperation over Rayleigh frequency flat fading channels is derived for perfect and imperfect spectrum acquisitions. Furthermore, the M-QO-STBC scheme is also proposed for use in wireless cognitive relay networks. MATLAB and Maple software based simulations are employed throughout the thesis to support the analytical results and assess the performance of new algorithms and methods.
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Leatham, Robert L. "Space-Time Coding for the Advanced Range Telemetry Continuous Phase Modulation." BYU ScholarsArchive, 2020. https://scholarsarchive.byu.edu/etd/8413.
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Aeronautical telemetry systems that transmit the same signal through multiple antennas from the flight vehicle suffer from severe link dropouts when the signals destructively interfere one with another at receiver. The underlying issue is a transmit array with element spacing far greater than the wavelength producing a transmit antenna pattern with significant and deep nulls. Recently, space-time coding techniques have been proven to resolve the issue for systems using linear modulations and shaped-offset quadrature shift keying (SOQPSK) modulation, a non-linear continuous phase modulation (CPM). This thesis examines application of space-time coding techniques to resolve the self-interference issue for another CPM modulation, the advanced range telemetry (ARTM) CPM. It is shown in this thesis among the two branches of space-time coding, space-time block coding (STBC) and space-time trellis coding (STTC), only the latter offers a solution for a full rate, low complexity, no hardware modification implementation. Various candidate STTCs are identified via simulation using the pair-wise error probability as a performance metric. One STTC is identified with trivial implementation costs and an error performance that is a function of code length.
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Tang, Yipeng. "DSP implementation of trellis coded modulation and distributed space time coding." Morgantown, W. Va. : [West Virginia University Libraries], 2001. http://etd.wvu.edu/templates/showETD.cfm?recnum=1796.
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Thesis (M.S.)--West Virginia University, 2001.Title from document title page. Document formatted into pages; contains v, 118, [64] p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 114-118).
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Tao, Meixia. "Space-time coding schemes for wireless communications over flat fading channels /." View Abstract or Full-Text, 2003. http://library.ust.hk/cgi/db/thesis.pl?ELEC%202003%20TAO.
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Thesis (Ph. D.)--Hong Kong University of Science and Technology, 2003.Includes bibliographical references (leaves 111-118). Also available in electronic version. Access restricted to campus users.
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Gong, Yi. "Space-time coding for high data-rate wireless communications over space and frequency selective fading channels /." View Abstract or Full-Text, 2002. http://library.ust.hk/cgi/db/thesis.pl?ELEC%202002%20GONG.
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Thesis (Ph. D.)--Hong Kong University of Science and Technology, 2002.Includes bibliographical references (leaves 105-114). Also available in electronic version. Access restricted to campus users.
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Takele, Berta. "Performance Evaluation of Simple Space-Time Block Coding on MIMO Communication System." Thesis, Växjö University, Växjö University, School of Mathematics and Systems Engineering, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:vxu:diva-6988.
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This thesis discuss on new technique called space time block coding (especially Alamouti's code) which is used to increase capacity and reliability of data transmission over time varying multi-path fading channel. The over all work of the thesis included in the following four chapters.
In chapter-1 we are going to cover some theoretical part which is useful to understand thesis work and in chapter-2 we will discuss the comparison between simple space time block code (Alamouti's code) and MRRC (Maximum Ratio Receiver Combining) which is receiver diversity and then in chapter-3 we will see the channel capacity & probability error performance for 2x2 Alamouti code over Rayleigh and Rice fading channel .Finally the conclusion and further work included in chapter-4.
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Wu, Nan. "Generalized space-time block coding for co-located and cooperative MIMO systems." Thesis, University of Southampton, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.494677.
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Eltayeb, Nasr Eldrin M. "Space-time coding for broadband point-to-point and collaborative wireless communications." Thesis, Loughborough University, 2009. https://dspace.lboro.ac.uk/2134/36006.
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The focus of this thesis is to leverage the spatial diversity gain afforded by point-to-point and collaborative multi-input multi-output (MIMO) wireless communications systems through the exploitation of space-time and space-frequency block coding. Both frequency-flat narrow band and frequency-selective broadband MIMO channels are considered. A new enhanced extended-orthogonal space-time block coding scheme is proposed for point-to-point closed-loop space-time block coding with four transmit antennas over frequency-flat MIMO channels. This method is confirmed by average bit error rate simulations to outperform both the established Alamouti scheme for two transmit antennas and a quasiorthogonal scheme for four transmit antennas. A receive antenna selection scheme is also proposed to further improve the performance of the proposed closed-loop extended orthogonal space-time scheme.