Rozprawy doktorskie na temat „Iterative detection”
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Shaheem, Asri. "Iterative detection for wireless communications". University of Western Australia. School of Electrical, Electronic and Computer Engineering, 2008. http://theses.library.uwa.edu.au/adt-WU2008.0223.
Pełny tekst źródłaMoher, Michael L. "Cross-entropy and iterative detection". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq22171.pdf.
Pełny tekst źródłaMoher, Michael L. Carleton University Dissertation Engineering Systems and Computer. "Cross-entropy and iterative detection". Ottawa, 1997.
Znajdź pełny tekst źródłaEl-Hajjar, Mohammed H. "Near-capacity MIMOs using iterative detection". Thesis, University of Southampton, 2008. https://eprints.soton.ac.uk/64487/.
Pełny tekst źródłaXu, Danfeng. "Iterative coded multiuser detection using LDPC codes". Thesis, University of Ottawa (Canada), 2007. http://hdl.handle.net/10393/27939.
Pełny tekst źródłaValenti, Matthew C. "Iterative Detection and Decoding for Wireless Communications". Diss., Virginia Tech, 1999. http://hdl.handle.net/10919/28290.
Pełny tekst źródłaPh. D.
Marsland, Ian D. "Iterative noncoherent detection of differentially encoded M-PSK". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0016/NQ46386.pdf.
Pełny tekst źródłaWong, Eddy. "Iterative decoding of coded GMSK with discriminator detection". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/MQ63037.pdf.
Pełny tekst źródłaWu, Zining. "Coding and iterative detection for magnetic recording channels /". Boston, Mass. [u.a.] : Kluwer Academic Publ, 2000. http://www.loc.gov/catdir/enhancements/fy0820/99049501-d.html.
Pełny tekst źródłaBalasubramanyam, Ramkumar. "Adaptive iterative multiuser detection for wireless communication systems". Thesis, University of Greenwich, 2008. http://gala.gre.ac.uk/8203/.
Pełny tekst źródłaBaik, Eugene. "Iterative detection for overloaded OFDMA with spatial diversity". Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/41254.
Pełny tekst źródłaIncludes bibliographical references (leaves 81-85).
Orthogonal Frequency Division Multiple Access (OFDMA) systems have built-in mechanisms to mitigate the effects of the wireless multipath channel but are limited in system capacity to available bandwidth. This shortcoming can be worked around through the process of "overloading," where users are additionally multiplexed in the spatial domain to each frequency resource. To efficiently resolve non-orthogonally multiplexed users within the system, sophisticated multiple antenna receivers with multiuser detection methods are necessary. The focus of this thesis will be the formulation of an iterative multiple antenna receiver framework for overloaded uplink OFDMA systems. Specifically, we formulate optimal MAP and reduced complexity MMSE symbol detection algorithms for the multiuser detection and single user decoding turbo loop. We verify the performance of each algorithm through Monte Carlo simulation with randomly generated multipath MIMO channels. From the results we determine the tradeoffs of algorithm complexity with performance and the effect of channel correlation on the supportable user load. Our MMSE algorithm with soft interference cancellation is observed to closely approach single user performance in low to moderately correlated MIMO channels after turbo loop iteration. Additionally, we observe that increasing the number of antennas relative to the number of overloaded users can mitigate the effects of moderate correlation to provide acceptable error performance.
by Eugene Baik.
M.Eng.
Chen, Min. "Iterative detection for overloaded multiuser MIMO OFDM systems". Thesis, University of York, 2013. http://etheses.whiterose.ac.uk/4644/.
Pełny tekst źródłaDangl, Markus A. "Iterative estimation and detection for single carrier block transmission". Tönning Lübeck Marburg Der Andere Verl, 2007. http://d-nb.info/986923419/04.
Pełny tekst źródłaYlioinas, J. (Jari). "Iterative detection, decoding, and channel estimation in MIMO-OFDM". Doctoral thesis, University of Oulu, 2010. http://urn.fi/urn:isbn:9789514262203.
Pełny tekst źródłaSun, Kyung Tae (John) Electrical Engineering & Telecommunications Faculty of Engineering UNSW. "Selective detection in an iterative soft interference cancellation receiver". Awarded by:University of New South Wales. School of Electrical Engineering and Telecommunications, 2006. http://handle.unsw.edu.au/1959.4/35224.
Pełny tekst źródłaAl-Rubaie, Alaa Abdulameer Saeed. "Iterative decoding and detection for physical layer network coding". Thesis, University of Newcastle upon Tyne, 2015. http://hdl.handle.net/10443/4062.
Pełny tekst źródłaPerrins, Erik. "SERIALLY CONCATENATED ARTM TIER I WAVEFORMS WITH ITERATIVE DETECTION". International Foundation for Telemetering, 2005. http://hdl.handle.net/10150/604921.
Pełny tekst źródłaWe investigate the performance of Feher-patented quadrature phase-shift keying (FQPSK) and shaped-offset QPSK (SOQPSK) when serially concatenated with an outer code. We show that the receiver complexity for FQPSK and SOQPSK can be greatly reduced by viewing them as continuous phase modulation (CPM) waveforms. We use the pulse amplitude modulation (PAM) representation of CPM, which allows near-optimum detection of both modulations using a simple 4-state trellis. We compare the performance of the PAM-based approximation with another common approximation known as frequency/phase pulse truncation (PT).We use both of these reduced-complexity designs in serially concatenated coding schemes with iterative detection. In the end, we show that the PAM approximation has a slight performance advantage over PT, but both approximations achieve large coding gains in the proposed serially concatenated systems.
Khan, Ejaz. "Iterative techniques for CDMA and algorithms for MIMO detection /". Paris : École nationale supérieure des télécommunications, 2004. http://catalogue.bnf.fr/ark:/12148/cb39240253x.
Pełny tekst źródłaLi, Peng. "Low-complexity iterative detection algorithms for multi-antenna systems". Thesis, University of York, 2011. http://etheses.whiterose.ac.uk/2192/.
Pełny tekst źródłaKusume, Katsutoshi [Verfasser]. "Iterative Multiuser Detection in Medium Access Control Design / Katsutoshi Kusume". München : Verlag Dr. Hut, 2010. http://d-nb.info/1009972707/34.
Pełny tekst źródłaYang, Tao Electrical Engineering & Telecommunications Faculty of Engineering UNSW. "Performance of iterative detection and decoding for MIMO-BICM systems". Awarded by:University of New South Wales. School of Electrical Engineering and Telecommunications, 2006. http://handle.unsw.edu.au/1959.4/26197.
Pełny tekst źródłaKarim, Md Anisul. "Weighted layered space-time code with iterative detection and decoding". Thesis, The University of Sydney, 2006. http://hdl.handle.net/2123/1095.
Pełny tekst źródłaKarim, Md Anisul. "Weighted layered space-time code with iterative detection and decoding". School of Electrical & Information Engineering, 2006. http://hdl.handle.net/2123/1095.
Pełny tekst źródłaMultiple antenna systems are an appealing candidate for emerging fourth-generation wireless networks due to its potential to exploit space diversity for increasing conveyed throughput without wasting bandwidth and power resources. Particularly, layered space-time architecture (LST) proposed by Foschini, is a technique to achieve a significant fraction of the theoretical capacity with a reasonable implementation complexity. There has been a great deal of challenges in the detection of space-time signal; especially to design a low-complexity detector, which can efficiently remove multi-layer interference and approach the interference free bound. The application of iterative principle to joint detection and decoding has been a promising approach. It has been shown that, the iterative receiver with parallel interference canceller (PIC) has a low linear complexity and near interference free performance. Furthermore, it is widely accepted that the performance of digital communication systems can be considerably improved once the channel state information (CSI) is used to optimize the transmit signal. In this thesis, the problem of the design of a power allocation strategy in LST architecture to simultaneously optimize coding, diversity and weighting gains is addressed. A more practical scenario is also considered by assuming imperfect CSI at the receiver. The effect of channel estimation errors in LST architecture with an iterative PIC receiver is investigated. It is shown that imperfect channel estimation at an LST receiver results in erroneous decision statistics at the very first iteration and this error propagates to the subsequent iterations, which ultimately leads to severe degradation of the overall performance. We design a transmit power allocation policy to take into account the imperfection in the channel estimation process. The transmit power of various layers is optimized through minimization of the average bit error rate (BER) of the LST architecture with a low complexity iterative PIC detector. At the receiver, the PIC detector performs both interference regeneration and cancellation simultaneously for all layers. A convolutional code is used as the constituent code. The iterative decoding principle is applied to pass the a posteriori probability estimates between the detector and decoders. The decoder is based on the maximum a posteriori (MAP) algorithms. A closed-form optimal solution for power allocation in terms of the minimum BER is obtained. In order to validate the effectiveness of the proposed schemes, substantial simulation results are provided.
Mutlu, Burcu O. "An extensive study on iterative solver resilience : characterization, detection and prediction". Doctoral thesis, Universitat Politècnica de Catalunya, 2019. http://hdl.handle.net/10803/668904.
Pełny tekst źródła“Soft errors” causados por cambios de estado transitorios en bits, tienen el potencial de impactar significativamente el comportamiento de una aplicación. Esto, ha motivado el diseño de una variedad de técnicas para detectar, aislar y corregir soft errors aplicadas a micro-arquitecturas, arquitecturas, tiempo de compilación y a nivel de aplicación para minimizar su impacto en la ejecución de una aplicación. El primer paso para diseñar una buna técnica de detección/corrección de errores, implica el conocimiento de las vulnerabilidades de la aplicación ante posibles soft errors. Este trabajo se centra en los efectos de la corrupción silenciosa de datos en soluciones iterativas, así como en los esfuerzos para mitigar esos efectos. En esta tesis, primeramente, presentamos la primera caracterización extensiva del impacto de soft errors sobre las características convergentes de seis métodos iterativos usando inyección de fallos a nivel de aplicación. Analizamos el impacto de los soft errors en términos del tipo de error (único vs múltiples-bits), de la distribución y posición de los bits afectados, las estructuras de datos, instrucciones afectadas y de las variaciones en el tiempo. Creamos una base de datos pública con más de 1.5 millones de resultados de inyección de fallos. Después, analizamos el desempeño de mecanismos de detección de soft errors actuales y presentamos los resultados de su comparación. Motivados por las observaciones de los resultados presentados, evaluamos un detector de soft errors basado en técnicas de machine learning que toma como entrada las características observadas en el tiempo de ejecución individual de los detectores anteriores al llegar a su conclusión. La evaluación de los resultados obtenidos muestra una mejora por sobre los detectores individualmente. Basados en estos resultados propusimos un método basado en machine learning para predecir el comportamiento de los errores en un programa con el fin de hacer el estudio de inyección de errores mas eficiente. Presentamos este método para evaluar el rendimiento de los detectores de soft errors. Demostramos que nuestro método mantiene una precisión del 84% en promedio con hasta un 53% de mejora en el tiempo de ejecución. También mostramos que una vez que un modelo ha sido entrenado, las pruebas de inyección de errores siguientes costarían 10% del tiempo esperado de ejecución.
Tsai, Meng-Ying (Brady). "Iterative joint detection and decoding of LDPC-Coded V-BLAST systems". Thesis, Kingston, Ont. : [s.n.], 2008. http://hdl.handle.net/1974/1304.
Pełny tekst źródłaKasparis, Christos. "Iterative signal processing techniques for improved multiuser detection and MIMO channel equalization". Thesis, University of Bristol, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.432727.
Pełny tekst źródłaKovintavewat, Piya. "Timing Recovery Based on Per-Survivor Processing". Diss., Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/4821.
Pełny tekst źródłaLo, Ernest Sze-Yuen. "Differential OFDM with iterative detection and signal space diversity for broadband wireless communication /". View Abstract or Full-Text, 2002. http://library.ust.hk/cgi/db/thesis.pl?ELEC%202002%20LO.
Pełny tekst źródłaIncludes bibliographical references (leaves 67-69). Also available in electronic version. Access restricted to campus users.
TACCA, BERNARDO. "Implementation of iterative multiuser joint detection techniques in a dvb-rcs satellite scenario". Doctoral thesis, Università degli Studi di Roma "Tor Vergata", 2009. http://hdl.handle.net/2108/902.
Pełny tekst źródłaWith the explosive growth of telecommunications, the efficient use of available spectrum is becoming increasingly important: tightened frequency reuse planning is a pressing need in satellite networks, as the frequency spectrum has become an extremely precious resource. The purpose of this work is to develop a novel methodology for improving the bandwidth utilization on the Reverse Link (RL) of a multibeam satellite. The proposed method permits the frequency reuse for adjacent beams (usually adjacent beams employ different modulation bands so as not to interfere at the satellite antennas) and mitigates the resulting Co-Channel Interference (CCI) using a suitable Multiuser Joint Detection (MUD) algorithm at the gateway side, that is all the channels are demodulated together in order to suppress the CCI interference. The reference scenario will be a satellite system where the gateway station supports a two-way communication with several interactive user terminals equipped with a relatively small aperture antenna and transmitting low power. The RL implements an enhanced DVB-RCS standard operating with low-rate TDMA users (data rates up to few Mbit/s), as this scheme is currently the most popular for the considered scenario. The selected MUD technique is based on the adaption of iterative (turbo) interference cancellation strategies presented in literature for CDMA systems. Complete demodulator simulations were performed in general scenarios representative of real cases. The simulations have demonstrated the proposed interference mitigation algorithm reasonable complexity and an effective CCI reduction. Detailed guidelines have been finally reported in the thesis.
Ma, Hannan. "Iterative row-column algorithms for two-dimensional intersymbol interference channel equalization complexity reduction and performance enhancement /". Pullman, Wash. : Washington State University, 2010. http://www.dissertations.wsu.edu/Thesis/Summer2010/h_ma_062110.pdf.
Pełny tekst źródłaTitle from PDF title page (viewed on July 28, 2010). "School of Electrical Engineering and Computer Science." Includes bibliographical references (p. 51).
Zhao, Qing. "Advanced Synchronization Techniques for Continuous Phase Modulation". Diss., Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/10486.
Pełny tekst źródłaJuntti, M. (Markku). "Multiuser demodulation for DS-CDMA systems in fading channels". Doctoral thesis, University of Oulu, 1997. http://urn.fi/urn:isbn:9514247558.
Pełny tekst źródłaRamchandran, Harish. "Low-complexity iterative detection techniques for slow-frequency-hop spread-spectrum communications with Reed-Solomon coding". Connect to this title online, 2007. http://etd.lib.clemson.edu/documents/1181250532/.
Pełny tekst źródłaSimarro, Haro Mª de los Angeles. "Effi cient algorithms for iterative detection and decoding in Multiple-Input and Multiple-Output Communication Systems". Doctoral thesis, Universitat Politècnica de València, 2017. http://hdl.handle.net/10251/86186.
Pełny tekst źródłaLa presente tesis se enmarca dentro de los sistemas de comunicaciones de múltiples antenas o sistemas MIMO. Hoy en día, estos sistemas presentan una de las tecnologías más prometedoras dentro de los sistemas comunicaciones inalámbricas. A través del uso de múltiples antenas en ambos lados, transmisor y receptor, la tasa de transmisión y la calidad de la misma es aumentada. Por otro lado, la tecnología MIMO puede ser utilizada en un escenario multiusuario, donde una estación base (BS) la cual está equipada con varias antenas, sirve a varios usuarios al mismo tiempo, estos usuarios comparten dimensión espacial causando interferencias multiusuario. Por todas estas razones, la tecnología MIMO ha sido adoptada en muchos de los estándares de comunicaciones de nueva generación. Por otro lado, la tecnología MIMO Masivo, en la cual la estación base está equipada con un gran número de antenas (cientos o miles) que sirve a muchos usuarios en el mismo recurso de tiempo-frecuencia. Sin embargo, las ventajas proporcionadas por los sistemas MIMO implican un aumento en el coste computacional requerido. Por ello, el diseño de receptores de baja complejidad es una cuestión importante en estos sistemas. Para conseguir esta finalidad, las principales contribuciones de la tesis se basan en la implementación de algoritmos de detección soft y esquemas de precodificación eficientes. En primer lugar, el problema de la detección soft eficiente en un sistema receptor sin iteración es abordado. Una descripción detallada sobre los detectores soft más empleados es presentada. Por otro lado, han sido propuestos dos algoritmos de bajo coste. El primer algoritmo está basado en el algoritmo Box Optimization Hard Detector (BOHD) y proporciona una baja complejidad de implementación logrando un buen rendimiento. El segundo de los algoritmos propuestos intenta reducir el coste computacional del conocido algoritmo Subspace Marginalization with Interference Suppression (SUMIS). En segundo lugar, han sido investidados detectores de entrada y salida soft (SISO, soft-input soft-output) los cuales son ejecutados en estructuras de recepción iterativa. El empleo de un receptor iterativo mejora el rendimiento del sistema con respecto a no realizar realimentación, pudiendo lograr la capacidad óptima. Por el contrario, el coste computacional se vuelve prohibitivo. En este contexto, tres algoritmos han sido presentados. Dos de ellos logran un rendimiento óptimo, reduciendo la complejidad de los detectores SISO óptimos que normalmente son empleados. Por el contrario, el otro algoritmo logra un rendimiento casi óptimo a baja complejidad. En la tercera parte, se ha abordado el problema de la precodificación. Se ha llevado a cabo un análisis de algunas de las técnicas de precodificación más usadas. En este contexto, se ha evaluado el impacto que el número de condición de la matriz de canal tiene en el rendimiento de los precodificadores. Además, se ha aprovechado este impacto para proponer un precodificador hibrido. Por otro lado, en MIMO Masivo, se ha propuesto un esquema precodificador. En la última parte de la tesis, la implementación paralela del algoritmo SUMIS es presentada. Varias estrategias sobre la paralelización del algoritmo han sido propuestas y evaluadas en dos plataformas diferentes: Unidad Central de Procesamiento multicore (multicore CPU) y Unidad de Procesamiento Gráfico (GPU). Las implementaciones paralelas consiguen una mejora de speedup. Estas implementaciones permiten simular para MIMO Masivo y de forma más rápida que por simulación convencional, un algo
La present tesi s'emmarca dins dels sistemes de comunicacions de múltiples antenes o sistemes MIMO. Avui dia, aquestos sistemes presenten una de les tecnologies més prometedora dins dels sistemes de comunicacions inalàmbriques. A través de l'ús de múltiples antenes en tots dos costats, transmissor y receptor, es pot augmentar la taxa de transmissió i la qualitat de la mateixa. D'altra banda, la tecnologia MIMO es pot utilitzar en un escenari multiusuari, on una estació base (BS) la qual està equipada amb diverses antenes serveix a diversos usuaris al mateix temps, aquests usuaris comparteixen dimensió espacial causant interferències multiusuari. Per totes aquestes raons, la tecnologia MIMO ha sigut adoptada en molts dels estàndars de comunicacions de nova generació. D'altra banda, la tecnologia MIMO Massiu, en la qual l'estació base està equipada amb un gran nombre d'antenes (centenars o milers) que serveix a molts usuaris en el mateix recurs de temps-freqüència. No obstant això, els avantatges proporcionats pels sistemes MIMO impliquen un augment en el cost computacional requerit. Per això, el disseny de receptors de baixa complexitat és una qüestió important en aquests sistemes. Per tal d'aconseguir esta finalitat, les principals contribucions de la tesi es basen en la implementació d'algoritmes de detecció soft i esquemes de precodificació eficients. En primer lloc, és abordat el problema de la detecció soft eficient en un sistema receptor sense interacció. Una descripció detallada dels detectors soft més emprats és presentada. D'altra banda, han sigut proposats dos algorismes de baix cost. El primer algorisme està basat en l'algorisme Box Optimization Hard Decoder (BOHD) i proporciona una baixa complexitat d'implementació aconseguint un bon resultat. El segon dels algorismes proposats intenta reduir el cost computacional del conegut algoritme Subspace Marginalization with Interference Suppression (SUMIS). En segon lloc, detectors d'entrada i eixidia soft (SISO, soft-input soft-output) els cuals són executats en estructures de recepció iterativa han sigut investigats. L'ocupació d'un receptor iteratiu millora el rendiment del sistema pel que fa a no realitzar realimentació, podent aconseguir la capacitat òptima. Per contra, el cost computacional es torna prohibitiu. En aquest context, tres algorismes han sigut presentats. Dos d'ells aconsegueixen un rendiment òptim, reduint la complexitat dels detectors SISO òptims que normalment són emprats. Per contra, l'altre algorisme aconsegueix un rendiment quasi òptim a baixa complexitat. En la tercera part, s'ha abordat el problema de la precodificació. S'ha dut a terme una anàlisi d'algunes de les tècniques de precodificació més usades, prestant especial atenció al seu rendiment i a la seua complexitat. Dins d'aquest context, l'impacte que el nombre de condició de la matriu de canal té en el rendiment dels precodificadors ha sigut avaluat. A més, aquest impacte ha sigut aprofitat per a proposar un precodificador híbrid , amb la finalitat de reduir la complexitat d'algorismes prèviament proposats. D'altra banda, en MIMO Massiu, un esquema precodificador ha sigut proposat. En l'última part, la implementació paral·lela de l'algorisme SUMIS és presentada. Diverses estratègies sobre la paral·lelizació de l'algorisme han sigut proposades i avaluades en dues plataformes diferents: multicore CPU i GPU. Les implementacions paral·leles aconsegueixen una millora de speedup quan el nombre d'àntenes o l'ordre de la constel·lació incrementen. D'aquesta manera, aquestes implementacions permeten simular per a MIMO Massiu, i de forma més ràpida que la simulació convencional.
Simarro Haro, MDLA. (2017). Effi cient algorithms for iterative detection and decoding in Multiple-Input and Multiple-Output Communication Systems [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/86186
TESIS
Ryan, Patricia L. "THE WILLINGNESS TO PAY FOR THE DETECTION AND TREATMENT OF VULNERABLE PLAQUE RELATED TO HEART ATTACKS". UKnowledge, 2007. http://uknowledge.uky.edu/gradschool_diss/535.
Pełny tekst źródłaLaw, Tung-man. "An iterative receiver with pilot-aided Kalman filter based channel estimation for wireless MC-CDMA communication systems". Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/hkuto/record/B38581668.
Pełny tekst źródłaLaw, Tung-man, i 羅東文. "An iterative receiver with pilot-aided Kalman filter based channel estimation for wireless MC-CDMA communication systems". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2007. http://hub.hku.hk/bib/B38581668.
Pełny tekst źródłaTervo, V. (Valtteri). "Joint multiuser power allocation and iterative multi-antenna receiver design". Doctoral thesis, Oulun yliopisto, 2015. http://urn.fi/urn:isbn:9789526207292.
Pełny tekst źródłaTiivistelmä Väitöskirjassa tutkitaan lähettimessä tapahtuvan tehoallokoinnin sekä vastaanottimessa tapahtuvan signaalin suodatuksen yhteisoptimointia monikäyttöön suunnatussa langattomassa moniantennikommunikaatiossa. Langattomien laitteiden lukumäärän kasvaessa energiatehokkuuden merkitys tiedonsiirtolinkkien suunnittelussa korostuu. Soluihin perustuvassa langattomassa tietoliikenteessä keskimääräisen tehonkulutuksen pienentäminen ylälinkkilähetyksessä (käyttäjältä tukiasemaan) on tärkeää käyttäjän kannalta, sillä se pidentää laitteen akun kestoa. Lähettimen tehovahvistimen (high power amplifier (HPA)) tehonkulutus on kuitenkin verrannollinen lähetyksen huipputehoon. Väitöskirjassa luodaaan uusia menetelmiä sekä vertaillaan tehoallokointia yhden kantoaallon taajuustason monikäyttöön (single carrier frequency division multiple access (SC-FDMA)) ja ortogonaalisen taajuustason monikäyttöön (orthogonal FDMA (OFDMA)) perustuvissa lähetysteknologioissa. Työn ensimmäisessä osiossa tavoitteena on keskimääräisen tehonkulutuksen pienentäminen monen käyttäjän ylälinkkikommunikaatiossa suunnittelemalla tehoallokointimenetelmä, joka ottaa huomioon iteratiivisen vastaanottimen konvergenssiominaisuudet. Työssä ehdotettu menetelmä takaa vastaanotetun informaation halutun laadun (quality of service (QoS)) riittävän monen vastaanottimessa tehdyn iteraation jälkeen. Huipputehon ja keskitehon suhteen (peak to average power ratio (PAPR)) pienentäminen missä tahansa lähetyksessä on hyödyllistä, sillä sen ansiosta voidaan käyttää energiatehokkaampia ja halvempia tehovahvistimia. Työn jälkimmäisessä osiossa tavoitteena on kontrolloida lähetetyn signaalin huipputehon ja keskitehon suhdetta. Työn ensimmäisessä osiossa esitetyn QoS-rajoitteen lisäksi tehoallokointia rajoitetaan symbolisekvenssikohtaisella PAPR-rajoitteella SCFDMA- ja OFDMA-lähetyksessä. Lisäksi esitetään tilastollinen menetelmä, jossa rajoitetaan lähetetyn signaalin tehon varianssia. Kun käytetään yhtäaikaisesti QoS- ja PAPR-rajoitteita, voidaan tiedonsiirtokanavaan suunnitella optimaalinen tehoallokointi ottaen huomioon tehovahvistimen epälineaarisuudet. Työssä esitetty PAPR-rajoite on kuitenkin geneerinen, ja se voidaan sovittaa mihin tahansa SCFDMA- tai OFDMA- optimointikehykseen. Työssä esitettävien optimointiongelmien tavoitteena on käyttäjien summatehon minimointi. Suurin osa työssä esiintyvistä ongelmista on ei-konvekseja, joten siinä esitetään kaksi vaihtoehtoista peräkkäinen konveksi approksimaatio (successive convex approximation (SCA)) -menetelmää kaikille ei-konvekseille rajoitteille. Numeeriset tulokset osoittavat, että esitetyt tehoallokointimenetelmät pienentävät merkittävästi keskimääräistä tehonkulutusta mahdollistaen lisäksi adaptiivisen PAPR-kontrolloinnin. Väitöskirjassa esitettyjen menetelmien avulla voidaan pidentää mobiilikäyttäjien akun kestoa sekä erityisesti parantaa solun reunakäyttäjien palvelun laatua
Tseng, Hsin-Wu, Jiahua Fan i Matthew A. Kupinski. "Assessing computed tomography image quality for combined detection and estimation tasks". SPIE-SOC PHOTO-OPTICAL INSTRUMENTATION ENGINEERS, 2017. http://hdl.handle.net/10150/626451.
Pełny tekst źródłaBorlenghi, Filippo Verfasser], Gerd [Akademischer Betreuer] [Ascheid, Heinrich [Akademischer Betreuer] Meyr i Andreas [Akademischer Betreuer] Burg. "Silicon implementation of iterative detection and decoding for multi-antenna receivers / Filippo Borlenghi ; Gerd Ascheid, Heinrich Meyr, Andreas Burg". Aachen : Universitätsbibliothek der RWTH Aachen, 2015. http://d-nb.info/1128597942/34.
Pełny tekst źródłaBorlenghi, Filippo [Verfasser], Gerd [Akademischer Betreuer] Ascheid, Heinrich [Akademischer Betreuer] Meyr i Andreas [Akademischer Betreuer] Burg. "Silicon implementation of iterative detection and decoding for multi-antenna receivers / Filippo Borlenghi ; Gerd Ascheid, Heinrich Meyr, Andreas Burg". Aachen : Universitätsbibliothek der RWTH Aachen, 2015. http://d-nb.info/1128597942/34.
Pełny tekst źródłaLin, Meng-Shiang, i 林孟翔. "Iterative Space-Time Transceiver for MIMO Detection". Thesis, 2006. http://ndltd.ncl.edu.tw/handle/60318111032872284413.
Pełny tekst źródła國立中正大學
電機工程所
94
Exploiting maximum likelihood decoder can obtain the optimal solutions in multiple input multiple output system, however, the system become complicated. Sphere decoder not only obtains the optimal solutions near ML decoder, but also has lower complexity than ML decoder. To find the optimal solutions, the algorithm of sphere decoder applies search tree algorithm mostly, and detects transmitted signals from lower bound to upper bound. In this thesis, different detection techniques include sphere decoder and expectation maximization algorithm comparing to other detection techniques, then applied in the space-time transceivers.
Hsieh, Be-Kai, i 謝弼凱. "Iterative Detection of Nonlinear Distorted OMM Signals". Thesis, 2004. http://ndltd.ncl.edu.tw/handle/28110256140441569858.
Pełny tekst źródła國立中央大學
通訊工程研究所
92
Orthogonally multiplexed modulation (OMM) signals are investigated in this thesis. The research is focused on the application of the iterative detection of nonlinearly distorted OMM signals. In this thesis, we employ the iterative detection method to reduce the nonlinear distortion in orthogonal multiplexing orthogonal amplitude modulation (OMOAM) and orthogonal multiplexing orthogonal phase modulation (OMOPM). Three nonlinear distortion models are employed, and the results show that the performance trend of OMM distorted by these three models using the iterative detection are the same.
Huang, Din-Hwa, i 黃汀華. "Iterative Detection of Product Coded OFDM signals". Thesis, 2005. http://ndltd.ncl.edu.tw/handle/38686198945543263128.
Pełny tekst źródła國立清華大學
工程與系統科學系
93
A benchmark in the development of product code is the invention of the iterative (turbo) decoding algorithm by Pyndiah. Pyndiah's algorithm works for any product code using linear block component codes. The turbo decoded product codes, now often referred to as turbo product codes (TPC) or block turbo codes (BTC), have the distinct merits of simple decoding, fast convergence, high code rate and very low (or no) error floor although their performance at the waterfall region is not as impressive as that of conventional turbo codes. This thesis explore the feasibility of using BTC in conjunction with the orthogonal frequency division multiplexing (OFDM) signals. Our focus is on the major receiver design concerns that dominate the error rate performance of the system, namely, the channel estimation and decoding algorithm. While no original estimation or decoding algorithm is proposed, we examine the performance of a joint iterative channel estimation and decoding approach. As for the transmitted waveform design, we check the impact of the interleaver and present a new class of BTC that we refer to as parallel concatenated product codes (PCPC). The PCPC has a structure similar to the conventional turbo code with the component codes replaced by systematic product codes. Numerical results indicate that it does outperform its BTC counterpart with a comparable code rate.
FERRARI, Gianluigi. "On iterative detection for channels with memory". Doctoral thesis, 2001. http://hdl.handle.net/11381/2500857.
Pełny tekst źródłaYang, Ying-Mu, i 楊穎穆. "Iterative Multiuser Detection for MIMO SC-FDMA Systems". Thesis, 2013. http://ndltd.ncl.edu.tw/handle/83712187122714923485.
Pełny tekst źródła國立中興大學
通訊工程研究所
101
With the increasing demand of multimedia services in wireless transmission nowadays, Multiple-Input Multiple-Output (MIMO) technologies are adopted in many standards to enhance the data rate and the link robustness. Among others, in 3GPP LTE (3rd Generation Partnership Project Long Term Evolution), it has been a common method. And the combination of the SC-FDMA modulation scheme for the uplink transmission scheme, to approach the demand for data transmission rates and error performance. Because of, SC-FDMA (Single Carrier Frequency Division Multiple Access) combines the desirable characteristics of OFDMA with the low PAPR (Peak-to-Average Power Ratio) of single-carrier transmission schemes. In this thesis, we using the Space Frequency block code (SFBC) applied on each transmitted block for the multiuser scenario. At receiver side, in order to reduce the search complexity, we can be used the Layered ORthogonal lattice Detector (LORD) algorithm, and combines the Turbo codes for MIMO SC-FDMA systems. Then utilize the Extrinsic Information from Maximum A Posteriori (MAP) decoder to cancel the Multiple Access Interference (MAI). Simulations for an uplink scenario assess the proposed algorithms in several situations.
Kind, Adriel P. "Iterative APP list-detection for multi-dimensional channels". 2004. http://arrow.unisa.edu.au:8081/1959.8/78226.
Pełny tekst źródłaOne measure of the size of a communication system is the number of independent data streams being transmitted simultaneously through a channel, assuming tight constraints on available bandwidth and signal power. Such data streams may originate from different users all wishing to communicate at once. In addition, each user may wish to transmit independent data on more than one antenna simultaneously in order to increase his or her own data rate. Although strategies for such multi-dimensional signalling have seen significant improvements in recent years, most of the techniques proposed in the literature still suffer from either poor performance or prohibitive complexity when the size of the system grows large.
This thesis is concerned primarily with supporting high system spectral-efficiencies in very large systems, while maintaining strong resistance to data errors with manageable complexity.
Iterative decoding, or Bayesian message-passing, is demonstrably able to approach closely the performance of an optical decoder for certain families of single-user error correction codes, with low computational complexity. The topic of this work, iterative list detection, is a technique for jointly decoding many independent data streams from multiple users and/or antennas, using powerful iterative decoding strategies developed for such single-user codes. The receiver strategies presented are based on the premise that iterative Bayesian decoding is capable of achieving performance very close to that of an optimal decoder for a multi-dimensional system, given certain assumptions on the system model. Other than this, iterative list detection makes no assumptions about the statistics of the interfering signals, linearity, or any other simplifying impositions. Rather, the method seeks only to approximate closely the probabilistic quantities dictated by the rules of the iterative decoding paradigm, which is by now well understood.
List detection itself refers to the computationally efficient calculation of signal probabilities conditioned on a noise-and-interference corrupted signal at the receiver, computed for each simultaneously transmitted signal. The calculation is the key step in the implementation of an iterative receiver for such a system.
After introducing the list detection strategy in the context of iterative receivers for multi-user MIMO channels, algorithms for optimal list detection are described. A new optimal list detection algorithm with some superior properties to other implementations in the literature is proposed. While still very computationally complex, performance results for optimal list detection are presented that demonstrate the effectiveness and utility of the paradigm, and provide a performance benchmark for any sub-optimal list detection technique. The performance is also compared with other techniques such as linear filters, providing an appreciation of the benefits of list detection.
An asymptotic large-systems analysis is then undertaken in order to determine the behaviour of a fundamental parameter that determines the complexity of list detection, specifically the number of terms in a certain summation. The minimum number of terms is derived under an accuracy constraint on the signal probabilities. Results demonstrate that the number of terms does not necessarily increase with the size of the system, and the conditions under which this is true are indicated.
The main contribution of the thesis is the development of a number or computationally efficient sub-optimal list detection algorithms. Various strategies are proposed for different system scenarios, resulting in near-optimal performance with complexity that adapts automatically to cope with changing channel conditions and interference. The performance of the new techniques is demonstrated via simulation in channels with various statistics, dimensionality and interference, showing significant improvements in terms of both error resistance and complexity over other proposed methods.
Thesis (PhDTelecommunications)--University of South Australia, 2004.
Lin, Yu-Wei, i 林育瑋. "Precise Object Detection using Iterative Superpixels Grouping Method". Thesis, 2013. http://ndltd.ncl.edu.tw/handle/wfx4tp.
Pełny tekst źródła中華大學
資訊工程學系碩士班
101
The region completeness of object detection is very crucial to video surveillance, such as the pedestrian and vehicles identifications. However, many conventional object detecting techniques can’t guarantee the object region completeness because the object detections can be affected by lighting or color variations. In order to overcome this problem, we propose the iterative superpixels grouping (ISPG) method to extract the precise object boundary and generate the object region with high completeness after the object detections. By extending the superpixel segmentation method, the proposed ISPG method can improve the inaccurate segmentation problem and guarantee the region completeness on the object regions. The larger the number of object pixels in each superpixel, the more possibility this superpixel belongs to the object region. Hence, the region completeness can be improved by merging the superpixels that are classified into the object. Experimental results show that the proposed method outperforms the some conventional objection method in terms of object completeness evaluations.
CHEN, YUN, i 陳雲. "Fault detection and location of iterative logic array". Thesis, 1990. http://ndltd.ncl.edu.tw/handle/24416569214981023057.
Pełny tekst źródłaHuang, Yan-Zhang, i 黃彥彰. "VLSI Design and Implementation of Iterative K-best Sphere Detector using Low Complexity Enumeration for Iterative Detection and Decoding Receivers". Thesis, 2019. http://ndltd.ncl.edu.tw/handle/8q7fnv.
Pełny tekst źródła元智大學
電機工程學系甲組
107
With the growth of wireless communication system, the frequency spectrum has been widely occupied by many wireless communication standards. Improving the spectral efficiency with the reasonable hardware complexity is a critical issue for the future communication standards. Many wireless communication standards at nowadays have adopted the multiple-input multiple-output (MIMO) technology which is a solution to support higher data rates and spectral efficiency. However, the transmitted signals will suffer from the inter symbol interference (ISI) effect using multiple antennas. Employing iterative detection and decoding (IDD) receiver in MIMO system was demonstrated to improve the system performance significantly with a reasonable hardware complexity. Based on the MIMO IDD receiver, we proposed a flexible sphere decoding architecture that can support multiple configurable antennas and modulation schemes. In order to achieve the Maximum Likelihood (ML) detection performance and lower computational complexity, we adopt two kinds of sphere decoding codes, K-best and iterative K-best algorithms. Although iterative detection can improve the system performance, it will greatly increase the computational complexity. We further proposed a low-complexity enumeration to reduce the computational complexity in iterative K-best sphere decoding. Using the 40nm CMOS technology, the implementation results show that the proposed enumeration algorithm reduces the computational complexity by 15% and 45% in high channel quality and low channel quality which compared with the conventional iterative K-best algorithm. Also, we use a pipelined design to optimize the architecture, and the operating frequency is hence improved up to 230 MHz with the core area 1.88 mm2. The throughput achieves 408 Mbps and 204 Mbps under 16-QAM and 4×4 antennas for K-best mode and iterative K-best mode, respectively. Consequently, the proposed sphere detector provides a better system performance and hardware efficiency.