Дисертації з теми "Orthogonal time frequency space"
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Lee, King F. "Space-time and space-frequency coded orthogonal frequency division multiplexing transmitter diversity techniques." Diss., Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/14981.
Повний текст джерелаWong, Kar Lun (Clarence). "Space-time-frequency channel estimation for multiple-antenna orthogonal frequency division multiplexing systems." Thesis, McGill University, 2007. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=100244.
Повний текст джерелаThe proposed STF channel estimator reduces to a time-frequency (TF) channel estimator when no spatial correlations exist. In another perspective, the lower-dimension TF channel estimator can be viewed as an STF channel estimator with spatial correlation mismatch for space-time-frequency selective channels.
Computer simulations were performed to study the mean-square-error (MSE) behavior with different pilot parameters. We then evaluate the suitability of our STF channel estimator on a space-frequency block coded OFDM system. Bit error rate (BER) performance degradation, with respect to perfect coherent detection, is limited to less than 2 dB at a BER of 10-5 in the modified 3GPP fast-fading suburban macro environment. Modifications to the 3GPP channel involves reducing the base station angle spread to imitate a high transmit spatial correlation scenario to emphasize the benefit of exploiting spatial correlation in our STF channel estimator.
Karaoglu, Bulent. "A comparison of frequency offset estimation methods in Orthogonal Frequency Division Multiplexing (OFDM) systems." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2004. http://library.nps.navy.mil/uhtbin/hyperion/04Dec%5FKaraoglu.pdf.
Повний текст джерелаThesis Advisor(s): Roberto Cristi, Murali Tummala. Includes bibliographical references (p. 45-46). Also available online.
Saglam, Halil Derya. "Simulation performance of multiple-input multiple-output systems employing single-carrier modulation and orthogonal frequency division multiplexing." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2004. http://library.nps.navy.mil/uhtbin/hyperion/04Dec%5FSaglam.pdf.
Повний текст джерелаThesis advisor(s): Murali Tummala, Roberto Cristi. Includes bibliographical references (p. 69-71). Also available online.
Owojaiye, Gbenga Adetokunbo. "Design and performance analysis of distributed space time coding schemes for cooperative wireless networks." Thesis, University of Hertfordshire, 2012. http://hdl.handle.net/2299/8970.
Повний текст джерелаMody, Apurva Narendra. "Signal Acquisition and Tracking for Fixed Wireless Access Multiple Input Multiple Output Orthogonal Frequency Division Multiplexing." Diss., Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/7624.
Повний текст джерелаAwwad, Elie. "Techniques émergentes de codage espace-temps pour les systèmes de communications optiques." Thesis, Paris, ENST, 2015. http://www.theses.fr/2015ENST0004/document.
Повний текст джерелаResearch in the field of optical fiber communications is advancing at a rapid pace in order to meet the growing needs for higher data rates. The main driving forces behind these advancements are the availability of multiple degrees of freedom in the optical fiber allowing for multiplexing more data: amplitude, phase and polarization state of the optical field, along with time and wavelength are already used in the deployed optical transmission systems. Yet, these systems are approaching their theoretical capacity limits and an extra dimension "space" is investigated to achieve the next capacity leap. However, packing several data channels in the same medium brings with it differential impairments and crosstalk that can seriously deteriorate the performance of the system. In this thesis, we focus on recent optical MIMO schemes based on polarization division multiplexing (PDM) and space division multiplexing (SDM). In both, we assess the performance penalties induced by non-unitary crosstalk and loss disparities among the channels arising from imperfections in the used optical components (fibers, amplifiers, multiplexers...), and suggest novel MIMO coding techniques known as Space-Time (ST) codes, initially designed for wireless multi-antenna channels, to mitigate them
Diameh, Yousef A. "The optimization of multiple antenna broadband wireless communications. A study of propagation, space-time coding and spatial envelope correlation in Multiple Input, Multiple Output radio systems." Thesis, University of Bradford, 2013. http://hdl.handle.net/10454/6361.
Повний текст джерелаDia'meh, Yousef Ali. "The optimization of multiple antenna broadband wireless communications : a study of propagation, space-time coding and spatial envelope correlation in Multiple Input, Multiple Output radio systems." Thesis, University of Bradford, 2013. http://hdl.handle.net/10454/6361.
Повний текст джерелаAnoh, Kelvin Ogbonnaya Okorie. "Advanced MIMO-OFDM technique for future high speed braodband wireless communications : a study of OFDM design, using wavelet transform, fractional fourier transform, fast fourier transform, doppler effect, space-time coding for multiple input, multiple output wireless communications systems." Thesis, University of Bradford, 2015. http://hdl.handle.net/10454/14400.
Повний текст джерелаAnoh, Kelvin O. O. "Advanced MIMO-OFDM technique for future high speed braodband wireless communications. A study of OFDM design, using wavelet transform, fractional fourier transform, fast fourier transform, doppler effect, space-time coding for multiple input, multiple output wireless communications systems." Thesis, University of Bradford, 2015. http://hdl.handle.net/10454/14400.
Повний текст джерелаRende, Deniz. "Bit-interleaved space-frequency coded modulation for orthogonal frequency-division multiplexing systems." [Gainesville, Fla.] : University of Florida, 2004. http://purl.fcla.edu/fcla/etd/UFE0006420.
Повний текст джерелаBouziane, R. "Real-time optical orthogonal frequency division multiplexing transceivers." Thesis, University College London (University of London), 2013. http://discovery.ucl.ac.uk/1383794/.
Повний текст джерелаTran, Le Chung. "Complex orthogonal space-time processing in wireless communications." Access electronically, 2006. http://www.library.uow.edu.au/adt-NWU/public/adt-NWU20060726.133841/index.html.
Повний текст джерелаAl-Ghadhban, Samir Naser. "Multi-layered Space Frequency Time Codes." Diss., Virginia Tech, 2005. http://hdl.handle.net/10919/29498.
Повний текст джерелаPh. D.
Deng, Yunfei 1974. "Simplified decoding for a Quasi-Orthogonal space-time code family." Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=81534.
Повний текст джерелаLin, 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.
Повний текст джерелаPapanastasiou, Dimitris. "Space velocity correlation in orthogonal time-of-flight mass spectrometry." Thesis, Manchester Metropolitan University, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.423073.
Повний текст джерелаHesse, Matthias. "L2-orthogonal space-time code design for continuous phase modulation." Nice, 2010. http://www.theses.fr/2010NICE4008.
Повний текст джерелаLes codes spatio-temporels orthogonaux par blocs (OSTBC) sont devenus populaires en ce qu'ils permettent de construire des systèmes de communications sans-fil à diversité maximale et à décodage simplifié par maximum de vraisemblance découplé. Cependant, ces codes reposent en général sur une orthogonalité ponctuelle, ce qui entraîne une dégradation bien connue du débit de transmission pour les systèmes à plus de deux antennes d'émission. Nous introduisons dans cette thèse le concept d'orthogonalité L2 pour les codes spatio-temporel (STC). Cette approche permet de généraliser naturellement la propriété d'orthogonalité ponctuelle pour des systèmes à codages spatio-temporels non-linéaires. Il devient alors possible de construire de nouveaux systèmes multi-antennes (MIMO) à faible complexité de décodage et gain de diversité maximal. De plus, contrairement aux systèmes reposant sur des codes linéaires orthogonaux, ces nouveaux systèmes ne présentent plus de limitation du débit de transmission pour plus de deux antennes. Nous détaillons la construction générale de diverses familles de codes spatio-temporels L2 à débit maximal reposant sur des modulations de phase continue (CPM) et ceci pour n'importe quel nombre d'antennes d'émission. L'orthogonalité L2 des systèmes construits est obtenue par un banc de fonctions de correction de phase qui induit la diversité par décalage en fréquence tout en maintenant la continuité de la phase pour chaque antenne. L'étude de ces codes permet de démontrer que les systèmes MIMO à décodage simplifié ainsi obtenus sont à diversité maximale et débit optimal. Enfin, notons que la construction de ces codes n'introduit aucune contrainte supplémentaire sur les paramètres des modulations de phase continue utilisées
Karacayir, Murat. "Space-time Codes." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12612028/index.pdf.
Повний текст джерелаCrescitelli, David M., and Patrick B. Kistner. "Enhanced detection of orthogonal radar waveforms using time-frequency and bi-frequency signal processing techniques." Thesis, Monterey, California. Naval Postgraduate School, 2008. http://hdl.handle.net/10945/3931.
Повний текст джерелаThis thesis investigates the periodic autocorrelation function (PACF) and periodic ambiguity function (PAF) for orthogonal continuous waveform (CW) modulations used in netted low probability of intercept (LPI) radar. Three orthogonal polyphase sequences and one frequency coding sequence are examined and their PACF and PAF characteristics are quantified. The Wigner-Ville distribution (WVD) and quadrature mirror filter bank (QMFB) timefrequency signal processing techniques and the cyclostationary bi-frequency technique (often used in non-cooperative intercept receivers) are used to detect the orthogonal CW signals and extract their parameters. The results shows that a combination of the techniques used were able to extract the basic signal parameters of bandwidth and code period from the polyphase waveforms and also the frequency hop slots and code length from the frequency coding sequence. The concept of using a swarm of unmanned aerial vehicles (UAV) is examined from the viewpoint of a coordinated group of netted intercept receivers in search of an LPI radar network.
Kistner, Patrick B. Crescitelli David M. "Enhanced detection of orthogonal radar waveforms using time-frequency and bi-frequency signal processing techniques." Monterey, Calif. : Naval Postgraduate School, 2008. http://edocs.nps.edu/npspubs/scholarly/theses/2008/Sept/08Sep%5FKistner.pdf.
Повний текст джерелаThesis Advisor(s): Pace, Phillip E. "September 2008." Description based on title screen as viewed on November 5, 2008. Includes bibliographical references (p. 115-116). Also available in print.
Hayes, Matthew. "Distributed quasi-orthogonal space-time coding in wireless cooperative relay networks." Thesis, Loughborough University, 2011. https://dspace.lboro.ac.uk/2134/9923.
Повний текст джерелаManna, Mustafa A. "Modified quasi-orthogonal space-time block coding in distributed wireless networks." Thesis, Loughborough University, 2015. https://dspace.lboro.ac.uk/2134/16629.
Повний текст джерелаMoore, Thomas Dean. "Analytic Study of Space-Time and Space-Frequency Adaptive Processing for Radio Frequency Interference Suppression." The Ohio State University, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=osu1037380239.
Повний текст джерелаChen, Wei Zhang Ruifeng. "Time- frequency- selective channel estimation of ofdm systems /." Philadelphia, Pa. : Drexel University, 2005. http://dspace.library.drexel.edu/handle/1860/616.
Повний текст джерелаShang, Lei, and lei shang@ieee org. "Modelling of Mobile Fading Channels with Fading Mitigation Techniques." RMIT University. Electrical and Computer Engineering, 2006. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20061222.113303.
Повний текст джерелаHassan, Mohamed Abdulla S. "Channel Estimation and Equalisation for Multicarrier Systems Employing Orthogonal Space-Time Block Code." Thesis, University of Newcastle Upon Tyne, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.519490.
Повний текст джерелаHussin, Mohamed Nuri Ahmed. "Diversity gain enhancement for extended orthogonal space-time block coding in wireless communications." Thesis, University of Strathclyde, 2013. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=22706.
Повний текст джерелаPotter, Chris, Kurt Kosbar, and Adam Panagos. "Hardware Discussion of a MIMO Wireless Communication System Using Orthogonal Space Time Block Codes." International Foundation for Telemetering, 2008. http://hdl.handle.net/10150/606194.
Повний текст джерелаAlthough multiple-input multiple-output (MIMO) systems have become increasingly popular, the existence of real time results to compare with those predicted by theory is still surprisingly limited. In this work the hardware description of a MIMO wireless communication system using orthogonal space time block codes (OSTBC) is discussed for two antennas at both the transmitter and receiver. A numerical example for a frequency flat time correlated channel is given to show the impact of channel estimation.
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.
Повний текст джерелаFrye, James M. "Extrapolation of time and frequency responses of resonant antennas using damped sinusoids and orthogonal polynomials." Connect to this title online, 2007. http://etd.lib.clemson.edu/documents/1181251706/.
Повний текст джерелаPatel, Ketan. "Frequency and time domain contact parameter estimation for space robotic operations." Thesis, McGill University, 2003. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=19579.
Повний текст джерелаChu, Alice Pin-Chen. "High-Rate Space-Time Block Codes in Frequency-Selective Fading Channels." Thesis, University of Canterbury. Electrical and Computer Engineering, 2012. http://hdl.handle.net/10092/10360.
Повний текст джерелаSurabhi, G. D. "On Orthogonal Time Frequency Space Modulation for Wireless Communications." Thesis, 2020. https://etd.iisc.ac.in/handle/2005/4461.
Повний текст джерелаOluwafemi, Ilesanmi Banjo. "Super-orthogonal space-time turbo coded OFDM systems." Thesis, 2012. http://hdl.handle.net/10413/8505.
Повний текст джерелаThesis (Ph.D.)-University of KwaZulu-Natal, Durban, 2012.
Fang, Ching-Geng, and 方清庚. "Space-Time Block Coding in Orthogonal Frequency Division Multiplexing System." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/48557163031437112666.
Повний текст джерела國立臺灣科技大學
電子工程系
91
A transmitter diversity scheme for wireless communications over frequency selective fading channels is presented. Space-time block coding has emerged as a mean of attaining a significant MRC (maximal ratio combining) diversity gain. Using two transmit antennas and one receive antenna, the proposed scheme provides the same diversity order as MRC with one transmit antenna and two receiving antennas. Existing implementations of Space-time block coding are limited to flat fading environments due to the high sensitivity to delay spreads. OFDM (Orthogonal frequency division multiplexing) with a sufficiently long cyclic prefix can convert frequcncy-selective fading channels into multiple flat fading subchannels. The proposed technique utilizes OFDM to transform frequency selective fading channels into multiple flat fading subchannels on which space-time block coding and space-frequency block coding is applied. A two-branch transmitter diversity system is implemented without bandwidth expansion and with a small increase in complexity beyond that of a conventional OFDM system. Simulation results verify that in slow fading environments, the proposed space-frequency OFDM transmitter diversity technique has the same performance as a space-time OFDM transmitter diversity system. However, its shows that better performance in the fast fading environments is attained by the former schemes.
Ying, Te-Chen, and 應德臻. "Space-Time Coding with a Delay Processor in Orthogonal Frequency Division Multiplexing System." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/51671312632174472182.
Повний текст джерела國立中央大學
通訊工程研究所
92
The diversity gain and coding gain are two important factors in wireless communications. We review the structures of trellis codes with a delay processor and space-time coding in chapter 2. The orthogonal frequency division multiplexing (OFDM) system can provide high spectral efficiency, and combat the interference between each OFDM symbol and the interference between each subcarrier in one OFDM symbol effectively. In chapter 3, we review two coded OFDM systems and compare their performance. In chapter 4, we concatenate space-time block coding with a delay processor and a signal mapper in OFDM system. We can get more diversity gains in frequency domain and enhance the abilities to resist fading in an OFDM symbol. The decoding complexities are decreased by the code design. We use iterative decoding, super trellis decoding and interleaving to improve the error performance for different number of resolvable paths and delay spreads.
Tsung-Yen, Tsai, and 蔡宗延. "Channel Estimation Technique for Space-Time Block Coded Orthogonal Frequency Division Multiplexing System." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/35634526574522357090.
Повний текст джерела國立交通大學
電子工程系
91
Bandwidth is a very important resource in the wireless communication system. Improving the reliability of the wireless communication system without bandwidth expansion is always an interesting research topic. In 1998, space-time block code (STBC) is proposed to solve this problem. The basic concept of STBC is equipping multiple transmit antennas and/or receive antennas in the system to improve the performance. For simplicity, we only consider the system equipped with one receive antenna and two transmit antennas in this thesis. The performance of STBC employed in conventional single-carrier system is usually poor in the frequency-selective fading channel. Therefore, we apply STBC to the orthogonal frequency division multiplexing (OFDM) system to form the space-time block coded orthogonal frequency division multiplexing (STBC-OFDM) system. OFDM can transform frequency-selective fading channel to multiple flat fading subchannels. Aided by OFDM, STBC-OFDM system can work quite well over the frequency-selective fading channel. Multi-channel estimation plays an important role in the STBC-OFDM system. In this thesis, we present two simple channel estimation methods by using pilot signals. The first method (method Ⅰ) is the comb-type pilot subcarrier arrangement, and the second method (method Ⅱ) is the block-type pilot subcarrier arrangement. We also show the simulation results of comparison between method Ⅰ and method Ⅱ. Finally, we consider the IEEE standard 802.16 WirelessMAN with STBC. Equipping one receive antenna and two transmit antennas to the IEEE 802.16 system without channel coding, we apply our two channel estimation methods to improve the performance. Simulations show that the performance of our channel estimation methods is 2~3 dB loss compared with the ideal channel estimation in the IEEE 802.16 environment.
"Issues on broadband wireless communication systems: channel estimation, frequency synchronization and space-time-frequency coding." Thesis, 2005. http://library.cuhk.edu.hk/record=b6073967.
Повний текст джерелаIncorporating OFDM into multiple-input multiple-output (MIMO) system, MIMO-OFDM has been shown to provide larger channel capacity and greater diversity gain. However, current coding schemes for MIMO-OFDM are either space-time coded (STC) OFDM without the guarantee of full diversity gains or space-frequency coding (SFC) with a greater loss of data rate. Furthermore, most existing STC and SFC have focused on quasi-static fading which is not practical for broadband wireless communications. When multi-band OFDM (MB-OFDM) is applied to ultra-wide band (UWB) communications, a high diversity can be obtained, but in the expense of a much lower (close to half) data rate. To address the limitations of existing coding schemes for broadband wireless communication systems, this thesis: (i) proposes a space-time-frequency coding (STFC) that can achieve maximum diversity and maximum symbol rate transmission over MIMO block-fading channels; (ii) derives a high-rate full-diversity SFC from STFC tailored for frequency-selective fading channels; and (iii) proposes a high-rate high-diversity algebraic time-frequency coding (ATFC) for MB-OFDM system.
Orthogonal frequency division multiplexing (OFDM) is an effective technique to eliminate ISI in broadband wireless communications. This thesis studies the problem of training-based OFDM channel estimation and proposes a training method that minimizes the number of pilots employed to achieve a desired bit error rate (BER) performance. A clustered pilot pattern is further proposed to enhance the BER performance. Focusing on OFDM frequency synchronization, this thesis also proposes a clustered pilot tones placement and a novel pilot sequence design for carrier frequency offset (CFO) compensation. The analytical and simulation results show that the root mean square error (RMSE) of the CFO estimate can be greatly reduced.
Zhang Wei.
"July 2005."
Adviser: Pak-Chung Ching.
Source: Dissertation Abstracts International, Volume: 67-01, Section: B, page: 0461.
Thesis (Ph.D.)--Chinese University of Hong Kong, 2005.
Includes bibliographical references (p. 126-143).
Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
Abstracts in English and Chinese.
School code: 1307.
Peng, Jeng-Gang, and 彭政綱. "The Semi-blind Zero Forcing Equalization in the Space-Time BlockCoded Orthogonal Frequency Division Multiplexing Systems." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/53033044986837229903.
Повний текст джерела中原大學
電子工程研究所
98
In the case of unknown transmission channel, space-time block code combined with orthogonal frequency division multiplexing system is decoded by the semi-blind zero forcing equalization, it can remove the cyclic prefix automatically and estimate the original transmitted symbols.
Huang, Zhi-Ting, and 黃誌廷. "Estimation of I/Q Imbalance and Carrier Frequency Offset for Orthogonal Space-Time Block Coded OFDM Systems." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/77124536409315874202.
Повний текст джерела國立臺灣大學
電信工程學研究所
100
Nowadays, direct-conversion radio frequency (RF) receivers become more appealing due to its cost advantage. However, orthogonal frequency division multiplexing (OFDM) systems with direct-conversion RF receivers are very sensitive to non-idealities at the front-end of receiver, such as I/Q imbalance and carrier frequency offset (CFO). These non-idealities at the receiver result in inter-carrier interference (ICI). Accurate estimates of the non-idealities and channel response are required in OFDM systems. This thesis studies the CFO estimation for OFDM systems with multiple transmit antennas. The thesis consists mainly of two parts. In the first part, we consider OFDM systems with 2 transmit antennas. The Alamouti code is employed at the transmitter and both ST-OFDM and SF-OFDM systems are considered. For these systems with 2 transmit antennas, we extend two known blind CFO estimation algorithms (which were derived for OFDM systems with one transmit antenna) to solve the CFO estimation problem in ST and SF-OFDM systems. IN the second part, we consider OFDM systems with 3 transmit antennas. Orthogonal space time block codes (OSTBC) codes are used to encode the single at the transmitter. For this system, we derive a new blind CFO estimation algorithm. The idea is to exploit the fact that the rate of OSTBC is only 3/4. We show how to exploit the redundant information in OSTBC for blind CFO estimation. Moreover, the problem of I/Q imbalance is also consider in the second part. At the end, we also provide numerical simulation to verify the performance of the proposed methods.
Das, Smarajit. "Low-PAPR, Low-delay, High-Rate Space-Time Block Codes From Orthogonal Designs." Thesis, 2009. https://etd.iisc.ac.in/handle/2005/1046.
Повний текст джерелаDas, Smarajit. "Low-PAPR, Low-delay, High-Rate Space-Time Block Codes From Orthogonal Designs." Thesis, 2009. http://hdl.handle.net/2005/1046.
Повний текст джерелаYang, Chieh-Chih, and 楊傑智. "On Frequency-Domain Equalization with Training-Based Channel Estimation for Orthogonal Space-Time Block Coded System via MIMO Frequency-Selective Fading Channels." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/02950626224237711536.
Повний текст джерела國立交通大學
電機與控制工程系所
95
We propose an instructive derivation for the generalized block-level orthogonal space-time block encoder, capable of achieving full spatial diversity via frequency- selective fading environment provided that channel order is known. Instead of dealing with special case and then extending the results intuitively, we provide an alternative by starting with the general signal model with multiple transmit and multiple receive antennas, from which a general form of block-level orthogonality is established. In particular, transmit diversity with more than two transmit antennas can be achieved without compromise by means of frequency-domain equalization, in contrast to the QO-STBC-based approach. Pairwise error probability analysis is derived, under certain assumption which is numerically supported by simulation results, for analytical verifications of our claim on full diversity, inclusive of transmit-receive diversity and the multipath one. Moreover, the encoder structure enables us to generalize a training-based channel estimation technique, originally proposed for flat-fading scenario, to the frequency-selective fading scenario. Surprisingly we even obtain similar optimality criteria for optimal training block design which in our case, the signal block are fixed as OSTBC-based and the design derivation reduces to derive optimal power constraint over the training blocks. The optimality criteria for the training blocks are easy to satisfy when randomness of signal constellation is not a concern. Simulation results validate our discussion of the behaviors of the least-squares and linear MMSE channel estimates.
Chi, Kung-Hong, and 紀坤宏. "Semi-Blind Channel Estimation of Space Time Block Code Orthogonal frequency-division multiplexing System by Using Subspace Algorithm." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/98482072879547258119.
Повний текст джерела中原大學
電子工程研究所
96
In this paper,a space time block code OFDM system was proposed that can increased the channel capacity。we analyzed a complex Alamouti code in OFDM,Multiple input multiple output system, base on this derivative, ,the Alamouti code can be encoded in real or complex form in OFDM system。The semi-blind channel estimation can improve the accuracy of the channel coefficients。
Hu, Hsu-Chia, and 胡煦佳. "Joint Blind Estimation of I/Q Imbalance and Carrier Frequency Offset for Orthogonal Space-Time Block Coded OFDM Systems." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/14940244071805934972.
Повний текст джерела國立臺灣大學
電信工程學研究所
102
Orthogonal frequency division multiplexing (OFDM) has recently received considerable interest for its advantages in high-bit-rate transmissions over frequency-selective fading channels. Space-time block coding (STBC) has emerged as a powerful approach to exploit spatial diversity and to combat fading in multiple-input multiple-output (MIMO) wireless communication systems. However, OFDM systems with direct-conversion RF receivers are very sensitive to non-idealities at the front-end of receiver, such as I/Q imbalance and carrier frequency o&;#8629;set (CFO). These non-idealities at the receiver result in intercarrier interference (ICI). Accurate estimates of the non-idealities and channel response are required in OFDM systems. This thesis studies the blind CFO and I/Q imbalance estimation for OFDM systems with multiple transmit antennas. The thesis consists of three parts. In the first part, we review an existing CFO and I/Q imbalance estimation method based on rank criterion. This method though gives good performance but not for joint estimation, it cannot estimate the I/Q imbalance in the presense of CFO. In order to solve this issue, we propose an improved method. In the second part, we propose a new rank criteron and group method for joint CFO and independent I/Q imbalance estimation. The proposed method exploits the redundant information in OSTBC for joint blind CFO and I/Q imbalance estimation. In the third part, we extend the proposed method to the estimation of frequency dependent I/Q imbalance in the presence of CFO. We also provide numerical simulation to verify the performance of the proposed methods.
Vijaya, Krishna A. "A Filterbank Precoding Framework For MIMO Frequency Selective Channels." Thesis, 2006. https://etd.iisc.ac.in/handle/2005/1084.
Повний текст джерелаVijaya, Krishna A. "A Filterbank Precoding Framework For MIMO Frequency Selective Channels." Thesis, 2006. http://hdl.handle.net/2005/1084.
Повний текст джерелаNaikoti, Ashwitha. "OTFS Transceivers Design using Deep Neural Networks." Thesis, 2021. https://etd.iisc.ac.in/handle/2005/5640.
Повний текст джерела