Tesis sobre el tema "Channel Estimation"
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Kane, Roma. "Multiuser TDMA channel estimation". Diss., Columbia, Mo. : University of Missouri-Columbia, 2004. http://hdl.handle.net/10355/5810.
Texto completoThe entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (June 30, 2006) Vita. Includes bibliographical references.
Song, Limeng. "ATSC DTV Channel Estimation". Thesis, Université Laval, 2009. http://www.theses.ulaval.ca/2009/26235/26235.pdf.
Texto completoShiao, Fu-Sheng. "Combined Channel Estimation and Turbo Equalization for Wireless Channels". Thesis, University of Canterbury. Electrical and Computer Engineering, 2007. http://hdl.handle.net/10092/1189.
Texto completoPotter, Chris. "Modeling Channel Estimation Error in Continuously Varying MIMO Channels". International Foundation for Telemetering, 2007. http://hdl.handle.net/10150/604490.
Texto completoThe accuracy of channel estimation plays a crucial role in the demodulation of data symbols sent across an unknown wireless medium. In this work a new analytical expression for the channel estimation error of a multiple input multiple output (MIMO) system is obtained when the wireless medium is continuously changing in the temporal domain. Numerical examples are provided to illustrate our findings.
Khan, Anwer Ali. "Iterative Decoding and Channel Estimation over Hidden Markov Fading Channels". Thesis, Virginia Tech, 2000. http://hdl.handle.net/10919/32470.
Texto completoSince the 1950s, hidden Markov models (HMMS) have seen widespread use in electrical engineering. Foremost has been their use in speech processing, pattern recognition, artificial intelligence, queuing theory, and communications theory. However, recent years have witnessed a renaissance in the application of HMMs to the analysis and simulation of digital communication systems. Typical applications have included signal estimation, frequency tracking, equalization, burst error characterization, and transmit power control. Of special significance to this thesis, however, has been the use of HMMs to model fading channels typical of wireless communications. This variegated use of HMMs is fueled by their ability to model time-varying systems with memory, their ability to yield closed form solutions to otherwise intractable analytic problems, and their ability to help facilitate simple hardware and/or software based implementations of simulation test-beds.
The aim of this thesis is to employ and exploit hidden Markov fading models within an iterative (turbo) decoding framework. Of particular importance is the problem of channel estimation, which is vital for realizing the large coding gains inherent in turbo coded schemes. This thesis shows that a Markov fading channel (MFC) can be conceptualized as a trellis, and that the transmission of a sequence over a MFC can be viewed as a trellis encoding process much like convolutional encoding. The thesis demonstrates that either maximum likelihood sequence estimation (MLSE) algorithms or maximum a posteriori (MAP) algorithms operating over the trellis defined by the MFC can be used for channel estimation. Furthermore, the thesis illustrates sequential and decision-directed techniques for using the aforementioned trellis based channel estimators en masse with an iterative decoder.
Master of Science
Dessalermos, Spyridon. "Undersea acoustic propagation channel estimation". Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2005. http://library.nps.navy.mil/uhtbin/hyperion/05Jun%5FDessalermos.pdf.
Texto completoThesis Advisor(s): Joseph Rice, Roberto Cristi. Includes bibliographical references (p. 117-119). Also available online.
Gurel, Ilker. "Channel Estimation For Ofdm Systems". Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/12606940/index.pdf.
Texto completoRichter, Andreas. "Estimation of radio channel parameters". Ilmenau : ISLE, 2005. http://deposit.d-nb.de/cgi-bin/dokserv?idn=981051421.
Texto completoCarroll, Brian Michael. "Analysis of Sparse Channel Estimation". The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1244045602.
Texto completoHo, Kenneth T. "Uplink channel estimation in WiMAX". College Park, Md. : University of Maryland, 2008. http://hdl.handle.net/1903/8214.
Texto completoThesis research directed by: Dept. of Electrical and Computer Engineering. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
Lu, Biao. "Wireline channel estimation and equalization /". Full text (PDF) from UMI/Dissertation Abstracts International, 2000. http://wwwlib.umi.com/cr/utexas/fullcit?p3004324.
Texto completoZeydan, Engin. "Channel Phase And Data Estimation In Slowly Fading Frequency Nonselective Channels". Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/12607419/index.pdf.
Texto completoMongol, Bayarpurev, Takaya Yamazato, Hiraku Okada y Masaaki Katayama. "Channel Estimation for BFDM/OQAM System in Dispersive Time-Varying Channels". IEEE, 2006. http://hdl.handle.net/2237/7762.
Texto completoSong, Xuegui. "Channel estimation techniques for OFDM systems in dispersive time-varying channels". Thesis, University of British Columbia, 2009. http://hdl.handle.net/2429/8897.
Texto completoWang, Yi. "Joint OFDM symbol detection and channel estimation over doubly selective channels". Thesis, McGill University, 2014. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=121486.
Texto completoLe multiplexage par répartition en fréquence orthogonale (OFDM, pour Orthogonal Frequency Division Multiplexing) est une technique prometteuse pour la transmission de données à haut débit. Il est largement utilisé dans les systèmes de communication sans fil actuels en raison de ses bonnes performances sur les canaux sélectifs en fréquence. Toutefois, les systèmes reposant sur l'OFDM sont sensibles aux variations de temps de voie, qui entraînent un brouillage inter-porteuses (ICI, pour Inter-Carrier Interference). En l'absence de méthodes de détection appropriée, ce brouillage peut réduire les performances. Les informations d'état de canal (CSI, pour Channel State Information) constituent un élément essentiel des divers systèmes de détection de données basés sur l'OFDM et leur acquisition est un facteur crucial, surtout sur les canaux variables en temps. La présente examine une technique permettant d'intégrer l'évaluation de canaux reposant sur un filtre de Kalman à une variante du décodage par sphères (SD, pour Sphere Decoding) adaptée à la détection OFDM. En modélisant le système d'OFDM dans le domaine fréquentiel comme un système « entrées multiples, sorties multiples » (MIMO, pour Multiple Input Multiple Output), nous obtenons une puissante technique de SD pour la détection des données. En tenant pour acquis que la matrice de canal est une matrice bande, il est possible de maintenir une complexité recelant le potentiel pour une implantation réelle du SD et d'obtenir des performances concurrentielles comparativement à d'autres systèmes existants. En ce qui a trait à l'acquisition des CSI, on utilise la méthode de l'« expansion de base » (BE, pour Basis Expansion) pour modéliser les canaux variables en temps et on crée un filtre de Kalman pour le suivi des variations de temps des canaux. Le filtre de Kalman utilise les retours de décisions tirés du SD. Il ne nécessite ainsi qu'une faible densité de symboles pilotes, ce qui accroît l'optimisation de la bande passante. Les performances de ce système sont évaluées à l'aide de simulations informatiques reposant sur la méthode de Monte-Carlo. Les résultats montrent que par rapport à l'algorithme mis en concurrence, ce système permet des gains de performance. Quand il est utilisé sur des canaux LTE (Long Term Evolution) modérément variables en temps, ce système atteint une bonne performance, même en présence de brouillage de la phase des porteuses.
Jain, Payal. "On the Impact of Channel and Channel Quality Estimation on Adaptive Modulation". Thesis, Virginia Tech, 2002. http://hdl.handle.net/10919/36072.
Texto completoMaster of Science
Patel, Chirag S. "Wireless channel modeling, simulation, and estimation". Diss., Available online, Georgia Institute of Technology, 2006, 2006. http://etd.gatech.edu/theses/available/etd-03282006-200818/.
Texto completoAndrew, Alfred, Committee Member ; Durgin, Gregory, Committee Member ; Li, Geoffrey, Committee Member ; Ingram, Mary Ann, Committee Member ; Stuber, Gordon, Committee Chair.
Xinzhu, Jin. "Channel Estimation Techniques of SC-FDMA". Thesis, Karlstad University, Faculty of Technology and Science, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-1262.
Texto completoAbstract
This master thesis investigates several di®erent channel estimation techniques in an SC-
FDMA (Single Carrier Frequency Division Multiple Access) system with parameters set
according to the standards of 3GPP LTE (3rd Generation Partnership Project Long Term
Evolution). 3GPP LTE is the name given to a project within the 3GPP to improve the
mobile phone standard to cope with future requirements. In this thesis, we ¯rst introduce
the SC-FDMA system, which is a transmission technique that utilizes single carrier mod-
ulation, then ¯ve types of estimators are investigated. Essential to all channel estimatiors
is the use of pilot symbols. In the last part we compare the performance of the channel
estimation techniques with each other in di®erent environments by analysing their symbol
error rates. All simulations are done in a Matlab environment.
Kim, JoonBeom. "Iterative Channel Estimation for Wireless Communications". Diss., Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/14064.
Texto completoAvan, Muhammet. "Joint Frequency Offset And Channel Estimation". Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/2/12610149/index.pdf.
Texto completoAhmed, Mohsin Niaz. "LTE Uplink Modeling and Channel Estimation". Thesis, Linköpings universitet, Datorteknik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-69571.
Texto completoAlli, Idd Pazi. "Channel estimation in mobile wireless systems". Thesis, KTH, Signalbehandling, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-98754.
Texto completoYi, Na. "Channel estimation for linear block transmissions". Thesis, University of Liverpool, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.426104.
Texto completoMai, Huiheng. "Iterative channel estimation for wireless communications". Thesis, University of York, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.433681.
Texto completoLindén, Erik. "Iterative Channel Estimation in LTE Uplink". Thesis, KTH, Kommunikationsteori, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-147128.
Texto completoEn algoritm for iterativ kanalestimering i LTE-upplank foreslas. Algoritmen harlag komplexitet jamfort med MMSE-estimering. En enkel polynomiell modellanvands for att undertrycka brus over OFDM-symboler och ett DCT-baseratlter anvands for att undertrycka brus over sub-barvagor.Algoritmen har testats med era kanalmodeller och visats ge en vinst pa cirka0:5 dB med tva estimeringsitrationer, jamfort med en icke-iterativ mottagare.Algoritmen har ocksa applicerats till en MIMO-situation.En jamforelse mellan den foreslagna algoritmen och turboutjamning hargjorts.
Hogstrom, Christopher. "SPARSE CHANNEL ESTIMATION FOR AERONAUTICAL TELEMETRY". International Foundation for Telemetering, 2016. http://hdl.handle.net/10150/624251.
Texto completoKleynhans, Waldo. "On channel estimation for mobile WiMAX". Diss., Pretoria : [s.n.], 2008. http://upetd.up.ac.za/thesis/available/etd-01262009-102433/.
Texto completoAbd, El-Sallam Amar. "Low order channel estimation for CDMA systems". Thesis, Curtin University, 2005. http://hdl.handle.net/20.500.11937/2420.
Texto completoSaad, Haea. "Enhanced Channel Estimation for MIMO-OFDM in 5G NR : or an analysis of the channel estimation performance". Thesis, Karlstads universitet, Institutionen för matematik och datavetenskap (from 2013), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-85070.
Texto completoSong, Liying Tugnait Jitendra K. "Channel estimation and equalization for doubly-selective channels using basis expansion models". Auburn, Ala, 2008. http://repo.lib.auburn.edu/EtdRoot/2008/SPRING/Electrical_and_Computer_Engineering/Dissertation/Song_Liying_29.pdf.
Texto completoHolm, Henrik. "Adaptive Coded Modulation Performance and Channel Estimation Tools for Flat Fading Channels". Doctoral thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for elektronikk og telekommunikasjon, 2002. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-2150.
Texto completoAktas, Emre. "Channel estimation and equalization for wireless communication systems in frequency selective channels /". The Ohio State University, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=osu1486546889382902.
Texto completoAbd, El-Sallam Amar. "Low order channel estimation for CDMA systems". Curtin University of Technology, Department of Electrical and Computer Engineering, 2005. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=16299.
Texto completoThe frequency domain approach for parsimonious channel estimation results in an efficient implementation of RAKE receivers in DS-CDMA systems. In this approach, we consider a training based strategy and estimate the channel delays and attenuation using the averaged periodogram and modified time delay estimation techniques. We then use model selection techniques such as the sphericity test and multiple hypotheses tests based on F-Statistics to identify the model order and select the significant channel paths. Simulations show that for a pre-defined level of significance, the proposed technique correctly identifies the significant channel parameters and the parsimonious RAKE receiver shows improved statistical as well as computational performance over classical methods. The time domain approach is based on the Bootstrap which is appropriate for the case when the distribution of the test statistics required by the multiple hypothesis tests is unknown. In this approach we also use short training data and model the channel response as an FIR filter with unknown length. Model parameters are then estimated using low complexity algorithms in the time domain. Based on these estimates, bootstrap based multiple hypotheses tests are applied to identify the non-zero coefficients of the FIR filter. Simulation results demonstrate the power of this technique for RAKE receivers in unknown noise environments. Finally we propose adaptive blind channel estimation algorithms for CDMA systems. Using only the spreading code of the user of interest and the received data sequence, four different adaptive blind estimation algorithms are proposed to estimate the impulse response of frequency selective and frequency non-selective fading channels. Also the idea is based on minimum variance receiver techniques. Tracking of a frequency selective varying fading channel is also considered.
A blind based hierarchical MDL model selection method is also proposed to select non-zero parameters of the channel response. Simulation results show that the proposed algorithms perform better than previously proposed algorithms. They have lower complexity and have a faster convergence rate. The proposed algorithms can also be applied to the design of adaptive blind channel estimation based RAKE receivers.
Yao, Ning. "Iterative algorithms for channel estimation and equalization /". View abstract or full-text, 2005. http://library.ust.hk/cgi/db/thesis.pl?ELEC%202005%20YAO.
Texto completoMheidat, Hakam. "Channel Estimation and Equalization for Cooperative Communication". Thesis, University of Waterloo, 2006. http://hdl.handle.net/10012/2852.
Texto completoA new form of realizing transmit diversity has been recently introduced under the name of user cooperation or cooperative diversity. The basic idea behind cooperative diversity rests on the observation that in a wireless environment, the signal transmitted by the source node is overheard by other nodes, which can be defined as "partners" or "relays". The source and its partners can jointly process and transmit their information, creating a "virtual antenna array" and therefore emulating transmit diversity.
Most of the ongoing research efforts in cooperative diversity assume frequency flat channels with perfect channel knowledge. However, in practical scenarios, e. g. broadband wireless networks, these assumptions do not apply. Frequency-selective fading and imperfect channel knowledge should be considered as a more realistic channel model. The development of equalization and channel estimation algorithms play a crucial element in the design of digital receivers as their accuracy determine the overall performance.
This dissertation creates a framework for designing and analyzing various time and frequency domain equalization schemes, i. e. distributed time reversal (D-TR) STBC, distributed single carrier frequency domain (D-SC-FDE) STBC, and distributed orthogonal frequency division multiplexing (D-OFDM) STBC schemes, for broadband cooperative communication systems. Exploiting the orthogonally embedded in D-STBCs, we were able to maintain low-decoding complexity for all underlying schemes, thus, making them excellent candidates for practical scenarios, such as multi-media broadband communication systems.
Furthermore, we propose and analyze various non-coherent and channel estimation algorithms to improve the quality and reliability of wireless communication networks. Specifically, we derive a non-coherent decoding rule which can be implemented in practice by a Viterbi-type algorithm. We demonstrate through the derivation of a pairwise error probability expression that the proposed non-coherent detector guarantees full diversity. Although this decoding rule has been derived assuming quasi-static channels, its inherent channel tracking capability allows its deployment over time-varying channels with a promising performance as a sub-optimal solution. As a possible alternative to non-coherent detection, we also investigate the performance of mismatched-coherent receiver, i. e. , coherent detection with imperfect channel estimation. Our performance analysis demonstrates that the mismatched-coherent receiver is able to collect the full diversity as its non-coherent competitor over quasi-static channels.
Finally, we investigate and analyze the effect of multiple antennas deployment at the cooperating terminals assuming different relaying techniques. We derive pairwise error probability expressions quantifying analytically the impact of multiple antenna deployment at the source, relay and/or destination terminals on the diversity order for each of the relaying methods under consideration.
Reyaz, Tarannum. "Iterative channel estimation for CDMA wireless systems". Thesis, University of York, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.485135.
Texto completoYe, Diliao. "Indoor Positioning based on Wireless Channel Estimation". Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-187440.
Texto completoKaats, Adrian. "Estimation of biological ion channel permeation properties". Thesis, McGill University, 2012. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=110344.
Texto completoCette thèse présente des méthodes pour évaluer plus précisément le coefficient de diffusion utilisé dans les simulations fondées sur la théorie du continuum de la perméation des canaux ioniques. On établit tout d'abord un cadre mathématique pour le calcul des coefficients de diffusion d'espèces sphériques lors d'une diffusion restreinte à un contenant arbitrairement délimité. On présente ensuite des méthodes pour standardiser les coordonnées d'atomes formant des canaux ioniques biologiques. En utilisant ces coordonnées standardisées, on démontre comment on peut représenter la surface d'un pore intérieur d'un canal ionique. On utilise alors cette représentation comme contenant ainsi que le cadre mathématique présenté précédemment afin d'évaluer le coefficient de diffusion dans le pore du canal. On applique ensuite ces méthodes à la gramicidine A (GA) pour calculer le coefficient de diffusion du pore de la GA, avec des résultats comparables à ceux obtenus par des simulations de dynamique moléculaire beaucoup plus complexes et coûteuses. Finalement, à l'aide du cadre mathématique servant à calculer le coefficient de diffusion, on formule des prévisions à propos de la diffusion dans des espaces très restreints, et on considère leur incidence sur la conception appliquée aux canaux ioniques.
Stirling, Iain G. "On multipath channel estimation for CDMA systems". Thesis, University of Strathclyde, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.415361.
Texto completoCOSTA, RENATA BRAZ FALCAO DA. "CHANNEL ESTIMATION OVER POWER LINE COMMUNICATIONS SYSTEMS". PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2007. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=11480@1.
Texto completoA utilização das linhas de potência para fins de comunicação vem recebendo grande atenção nos últimos anos, principalmente devido a grande demanda por serviços de telecomunicações. A grande virtude é que as linhas de potência para comunicação apresentam uma solução sem a necessidade de nova fiação. Além disso, apresentam saída de potência disponível em todos os cômodos de uma residência, onde o terminal de comunicação possa ser usado, são de fácil instalação e acima de tudo apresentam custo reduzido. Sendo assim a comunicação através de linhas de potência vem se mostrando uma solução viável na oferta de serviços de telecomunicações. Esta tese investigou os sistemas PLC no que diz respeito à estimação do canal. Foi desenvolvido um método paramétrico de estimação do canal PLC baseado no algoritmo EM (Expectation Maximization). Foi feita a avaliação de desempenho combinando modulação OFDM (Orthogonal Frequency Division Multiplexing), estimação do canal PLC e equalização, sendo utilizado como referencias os equalizadores ZF (Zero Forcing) e MMSE (Minimum Mean Square Error).
The powerline communications systems have been receiving increasing attention in last few years. Power line communications presents a no new wires solution with the additional advantages of ubiquitous node availability, easy installation, and cost effectiveness. This thesis investigation the powerline estimation channel. It was presented parametric channel estimation method using EM (Expectation Maximization) algorithm. The performance using OFDM (Orthogonal Frequency Division Multiplexing), PLC Channel estimation and equalization was availability. The performance was studied using two equalization techniques Zero- Forcing and Minimum Mean Square Error.
Beek, Jaap van de. "Synchronization and channel estimation in OFDM systems". Doctoral thesis, Luleå tekniska universitet, Signaler och system, 1998. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-18017.
Texto completoGodkänd; 1998; 20061122 (haneit)
Trepkowski, Rose E. "Channel Estimation Strategies for Coded MIMO Systems". Thesis, Virginia Tech, 2004. http://hdl.handle.net/10919/10062.
Texto completoMaster of Science
Wang, Fei. "Pilot-Based Channel Estimation in OFDM System". University of Toledo / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1302129482.
Texto completoBerna, Gedik. "Channel estimation for Amplify and Forward Channels". Thesis, 2008. http://hdl.handle.net/10012/3688.
Texto completoKao, Chen-Wei y 高禎唯. "Nearby Channel V.S. Blind Channel Estimation". Thesis, 2016. http://ndltd.ncl.edu.tw/handle/48584281818353785127.
Texto completo國立臺灣海洋大學
通訊與導航工程學系
104
With advancing technology, almost everyone has a mobile phone. Consider a simple and static environment: user A is communicating with base station through channel A by mobile phone and nearby, user B is not using phone. In [13], we know that if a transmitted signal pass through two similar channels, the power distribution of received signals in frequency domain are also similar. Therefore, we hope to abstract some information from user B to support user A. In this paper, we assume the following situation. We estimate channel A by a Blind Subspace Method and obtain channel B information by a Pilot-Assisted Channel Estimation Method. We apply channel B’s information (channel B’s coefficient) to a Blind Subspace Method. The simulation results show that if correlation coefficient is 0.9, i.e. channel A is very similar to channel B, then the converging rates of the Subspace Method is faster. However, while correlation coefficients are 0.6 and 0.1, channel B’s information cannot provide any benefit to channel A because of these are different channels.
Wan, Ping. "Channel estimation for OFDM in fast fading channels". Thesis, 2011. http://hdl.handle.net/1828/3413.
Texto completoGraduate
"ATSC DTV Channel Estimation". Thesis, Université Laval, 2009. http://www.theses.ulaval.ca/2009/26235/26235.pdf.
Texto completoLiao, Jing-Luen y 廖經倫. "The Impact of Estimation Error on Channel Estimation-Based Equalizer for UWA Channel". Thesis, 2011. http://ndltd.ncl.edu.tw/handle/68785692990239570269.
Texto completo國立臺灣大學
電信工程學研究所
99
Underwater acoustic channels are generally recognized as one of the most difficult communication media in use today. The ocean is a time and spatially varying propagation environment. The underwater acoustic propagation is best supported at low frequencies, and the bandwidth available for communication is extremely limited. The underwater acoustic communication differ from RF communication in two aspects: One is the long multipath delay time that containing ten to hundreds of symbols, and the other is the rapid time variation of underwater acoustic channel. The receiver structure that has been found useful in many applications is a decision-feedback equalizer(DFE). Due to the nature of the propagation channel, the required signal processing is often prohibitively complex, to reduce computational complexity of signal processing, the receiver structures that are matched to the physical channel characteristics are investigates. A channel estimation-based equalization which relies on an adaptive channel estimation to compute its parameters, this estimation is used to cancel the post-cursor ISI before the linear equalization. The impact of estimation error on the channel estimation-based equalizer are investigated.
Jin, Jinghua. "Diversity receiver design and channel statistic estimation in fading channels /". 2006.
Buscar texto completoGuo-Jiun, shiau y 蕭國濬. "Kalman Channel Estimation for MIMO Systems in Flat Fading Channels". Thesis, 2003. http://ndltd.ncl.edu.tw/handle/77170985239996814402.
Texto completo國立臺北科技大學
電腦通訊與控制研究所
91
Recently, a wireless communication architecture known as Vertical BLAST (Bell Laboratories layered Space-Time) or V-BLAST could achieve high spectral efficiency by using multiple transmit and receive antennas. Unfortunately, the channel estimation error results in the poor performance in a V-BLAST system. A modified nulling vector which minimizes the power of various terms generated by the channel estimation errors has been also proposed. However, it still assumes that the channels are fixed during a data block (quasi-static). In this paper, we use Kalman filter to estimate the time-varying channel coefficients within a data block and perform the V-BLAST nulling and modified nulling. We consider the channel-variation in a data block, which is more practical environment. Via simulations, we show the performance improvement of the proposed system.