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Abdelaziz, Amr Mohamed. "Information Theoretical Studies on MIMO Channel with Limited Channel State Information". The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1500592938716914.
Pełny tekst źródłaPastore, Adriano. "Communication rates for fading channels with imperfect channel-state information". Doctoral thesis, Universitat Politècnica de Catalunya, 2014. http://hdl.handle.net/10803/279247.
Pełny tekst źródłaAquesta tesi estudia les taxes d'informació per la transmissió fiable d'informació en canals amb esvaïments sota la hipòtesi realista de que el receptor té un coneixement tan sols imperfecte de l'esvaïment aleatori. De particular interès són les expressions analítiques de les taxes de transmissió assolibles amb coneixement imperfecte i sense coneixement de l'estat del canal, és a dir, cotes inferiors de la informació mútua i de la capacitat de Shannon. Una cota inferior de la informació mútua per a codis gaussians ben coneguda s'obté combinant el soroll additiu (tèrmic) amb el terme de soroll multiplicatiu causat per les imperfeccions del coneixement de l'estat del canal en un únic soroll efectiu, i assumint que el soroll és gaussià i independent. Aquesta aproximació del pitjor soroll permet obtenir una expressió molt simple i ben coneguda de la informació mútua del canal. Una primera part d'aquesta tesi proposa un procediment senzill per a millorar aquesta cota associada al pitjor cas mitjançant una estratègia de repartiment de taxa: expressant l'entrada gaussiana del canal com a la suma de diverses entrades gaussianes independents i suposant que el receptor realitza una descodificació seqüencial dels fluxos d'informació, es mostra com obtenir una major cota inferior de la informació mútua del canal. En canals amb una única antena en transmissió, la distribució òptima de potència als diferents fluxos s'obté quan el seu nombre (capes) tendeix a infinit, i la potència associada a cada capa tendeix a zero. El límit associat a un nombre infinit de capes dóna lloc a una expressió integral de la cota de la informació mútua. En canals amb múltiples antenes s'obté un resultat similar. No obstant això, atès que la utilització de múltiples antenes proporciona més possibilitats de multiplexat espacial, el procediment dóna lloc a tota una família de cotes inferiors de la informació mútua associades a una combinació de capes infinita. S'estudia en detall aquesta família de cotes per al cas de coeficients d'esvaïments gaussians de mitjana zero, independents i idènticament distribuïts (conegut com esvaïment i.i.d. Rayleigh). S'obtenen diverses propietats de la família de cotes. És important destacar que per a coneixement asimptòtic perfecte del canal en recepció, qualsevol membre de la família de cotes és asimptòticament ajustat per alta relació senyal a soroll (SNR). En concret, la diferència entre la informació mútua i la seva cota inferior tendeix a zero quan la SNR tendeix a infinit sempre que el coneixement del canal tendeixi a ser exacte a mesura que la SNR tendeix a infinit. Una segona part d'aquesta tesi proposa un marc per a l'optimització d'una classe de funcions d'utilitat en canals amb múltiples antenes i esvaïments Rayleigh per blocs amb correlació en transmissió i sense informació sobre el canal a recepció. Una fracció temporal de cada bloc d'esvaïment es reserva per transmetre una seqüència de símbols d'entrenament mentre que la resta de mostres temporals s'utilitzen per transmetre informació. El receptor estima la matriu del canal partint de la seva observació sorollosa i descodifica la informació mitjançant la seva estimació del canal. Per a una classe de funcions d'utilitat que són funcions simètriques dels autovalors de la SNR matricial efectiva, els problemes consistents en optimitzar la seqüència pilot i el precodificador lineal són transformats en problemes convexos (o quasi-convexos) per a funcions d'utilitat còncaves (o quasi-còncaves). També s'estudia un subproblema important de l'optimització conjunta, que consisteix en el càlcul de les seqüències d'entrenament i dels precodificadors conjuntament Pareto-òptims. Integrant aquests procediments d'optimització en una iteració cíclica, s'obté un algoritme que convergeix a un òptim local conjunt per a qualsevol utilitat quasi-còncava
Yang, Jingnong. "Channel State Information in Multiple Antenna Systems". Diss., Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/14120.
Pełny tekst źródłaChen, Luan. "Enhancing indoor location fingerprinting using channel state information". Electronic Thesis or Diss., Paris, CNAM, 2020. http://www.theses.fr/2020CNAM1281.
Pełny tekst źródłaWith expeditious development of wireless communications, Location Fingerprinting (LF) has nurtured considerable indoor location based services in the field of Internet of Things. In this thesis, we first proposed EntLoc system, which adopts Autoregressive (AR) modeling entropy of the Channel State Information (CSI) amplitude as location fingerprint. It shares the structural simplicity of the Received Signal Strength (RSS) while reserving the most location-specific statistical channel information. Moreover, an upgraded AngLoc system is further designed, whose additional angle of arrival (AoA) fingerprint can be accurately retrieved from CSI phase through an enhanced subspace based algorithm, which serves to further eliminate the error-prone Reference Point (RP) candidates. In the LF online phase, by exploiting both CSI amplitude and phase information, a novel bivariate kernel regression scheme is proposed to precisely infer the target’s location. Results from extensive indoor experiments validate the superior localization performance of our proposed system over previous approaches
Huang, Jinliang. "Adaptive MIMO Systems with Channel State Information at Transmitter". Doctoral thesis, KTH, Kommunikationssystem, CoS, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-9777.
Pełny tekst źródłaQC 20100812
Ma, Yongsen. "Improving Wifi Sensing And Networking With Channel State Information". W&M ScholarWorks, 2019. https://scholarworks.wm.edu/etd/1593091976.
Pełny tekst źródłaHuang, Jin Liang. "Adaptive MIMO systems with channel state information at transmitter /". Stockholm : KTH Information and Communication Technology, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-9777.
Pełny tekst źródłaMi, De. "Massive MIMO with imperfect channel state information and practical limitations". Thesis, University of Surrey, 2017. http://epubs.surrey.ac.uk/841236/.
Pełny tekst źródłaJetlund, Ola. "Adaptive coded modulation : design and simulation with realistic channel state information". Doctoral thesis, Norwegian University of Science and Technology, Department of Electronics and Telecommunications, 2005. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-818.
Pełny tekst źródłaSpectrally efficient transmission schemes are becoming a more common requirement for digital communication systems. Especially in wireless communication since the bandwidth of available frequencies is a shared resource. In addition, wireless communication systems suffer from transmission media with varying conditions. Adaptive coded modulation (ACM) has been suggested as a bandwidth-efficient transmission technique in wireless fading environments. The use of ACM is motivated by its ability to improve spectral efficiency (SE) by adapting the transmission rates to the variations in channel signal-to-noise ratio. Any ACM scheme rely on being able to predict future states of the transmission medium. Under idealized conditions, such as the prediction being perfect, an ACM scheme can be configured to maximize the SE under the condition of the bit error rate (BER) being below a specified target BER. Here, computer simulations of an example system show that such systems in some cases fail to achieve the target BER, since the idealized conditions used in the design process do not hold in a realistic setup.
By limiting the number of transmission modes, introducing imperfect prediction, and other practical conditions such as delay in the communication system and probability of outage, a more practical ACM scheme can be considered. We show that it is still possible to optimize the performance of such schemes. A wireless communication channel with a Rayleigh fading envelope is assumed here since most results then can be presented in closed form expressions. For other distributions of the fading, results can be found numerically. By optimizing the performance of an idealized ACM scheme using capacity achieving channel codes, we have been able to upper bound the SE of practical ACM schemes. The results also provide us with a technique to control the average BER in the case of imperfect knowledge of future channel states. Simulation results for a modified ACM scheme that uses this technique is shown to have an average BER that is less than the target BER
Huang, Wei. "Linear transceiver design in MIMO system with imperfect channel state information /". View abstract or full-text, 2007. http://library.ust.hk/cgi/db/thesis.pl?ECE%202007%20HUANG.
Pełny tekst źródłaHe, Wenmin. "Cooperative Channel State Information Dissemination Schemes in Wireless Ad-hoc Networks". Digital WPI, 2013. https://digitalcommons.wpi.edu/etd-theses/288.
Pełny tekst źródłaYao, Weijie. "Fine-Grained Hand Pose Estimation System based on Channel State Information". The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1593211557742674.
Pełny tekst źródłaSacristán, Murga Daniel Francisco. "Feedback of channel state information in multi-antenna systems based on quantization of channel Gram matrices". Doctoral thesis, Universitat Politècnica de Catalunya, 2012. http://hdl.handle.net/10803/124839.
Pełny tekst źródłaEn un mundo cada vez más interconectado, donde hay una clara tendencia hacia un mayor número de comunicaciones inalámbricas simultáneas (comunicaciones M2M: Machine to Machine, redes de sensores, etc.) y en el que las necesidades de capacidad de transmisión de los enlaces de comunicaciones aumentan de manera vertiginosa (audio, video, contenidos multimedia, alta definición, etc.) el problema de la interferencia se convierte en uno de los factores limitadores de los enlaces junto con los desvanecimientos del nivel de señal y las pérdidas de propagación. Por este motivo los sistemas que emplean múltiples antenas tanto en la transmisión como en la recepción (los llamados sistemas MIMO: Multiple-Input Multiple-Output) se presentan como una de las soluciones más interesantes para satisfacer los crecientes requisitos de capacidad y comportamiento relativo a interferencias. Los sistemas MIMO permiten obtener un mejor rendimiento en términos de tasa de transmisión de información y a su vez son más robustos frente a ruido e interferencias en el canal. Esto significa que pueden usarse para aumentar la capacidad de los enlaces de comunicaciones actuales o para reducir drásticamente el consumo energético manteniendo las mismas prestaciones. Por otro lado, además de estas claras ventajas, los sistemas MIMO introducen un punto de complejidad adicional puesto que para aprovechar al máximo las posibilidades de estos sistemas es necesario tener conocimiento de la información de estado del canal (CSI: Channel State Information) tanto en el transmisor como en el receptor. Esta CSI se obtiene mediante estimación de canal en el receptor y posteriormente se envía al transmisor a través de un canal de realimentación. Esta tesis trata sobre el diseño del canal de realimentación para la transmisión de CSI, que es un elemento fundamental de los sistemas de comunicaciones del presente y del futuro. Las técnicas de transmisión que consideran activamente el efecto de la interferencia y el ruido requieren adaptarse al canal y, para ello, la realimentación de CSI es necesaria. En esta tesis se identifica, en primer lugar, la mínima información sobre el estado del canal necesaria para implementar un diseño óptimo en el transmisor, con el fin de evitar transmitir información redundante y obtener así un sistema más eficiente. Esta información es la matriz de Gram del canal MIMO. Seguidamente, se desarrolla un algoritmo de cuantificación adaptado a la geometría diferencial del conjunto que contiene la información a cuantificar y que además aprovecha la correlación temporal existente en los canales de propagación inalámbricos. Este algoritmo se implementa y evalúa primero en comunicaciones MIMO punto a punto entre dos usuarios, después se implementa para algunos casos particulares con múltiples usuarios, y finalmente se amplía para el caso general de sistemas broadcast multi-usuario. Adicionalmente, esta tesis también estudia y optimiza el dimensionamiento del canal de realimentación en función de la cantidad de recursos radio disponibles, en términos de ancho de banda, tiempo y potencia de transmisión. Para ello presenta el problema de la distribución óptima de dichos recursos radio entre el enlace de transmisión de datos y el enlace de realimentación para transmisión de información sobre estado del canal como un problema de optimización.
Pascual, Iserte Antonio. "Channel state Information and joint transmitter-receiver design in multi-antenna systems". Doctoral thesis, Universitat Politècnica de Catalunya, 2005. http://hdl.handle.net/10803/6890.
Pełny tekst źródłaEl objetivo es diseñar conjuntamente el transmisor y el receptor, lo que depende directamente de la calidad y la cantidad de información del canal de la que se dispone. En esta tesis se analiza el impacto de dicha información en el diseño.
Primero se ha estudiado un sistema MIMO de un único usuario usando la modulación orthogonal frequency division multiplexing (OFDM) y asumiendo un conocimiento perfecto del canal en ambos extremos. La arquitectura propuesta se basa en conformación conjunta por portadora, calculándose los conformadores óptimos y proponiéndose diversas estrategias de distribución de potencia entre las portadoras con una baja complejidad. Se han analizado también las relaciones asintóticas de estas distribuciones de potencia con otras soluciones clásicas con mayor coste.
El diseño anterior se ha extendido a sistemas MIMO multiusuario, donde todos los terminales en el escenario tienen más de una antena y la información del canal es perfecta. El objetivo es la minimización de la potencia total transmitida sujeto a restricciones de tasa de error máxima para cada enlace. El problema matemático obtenido es no convexo, por lo que estrategias clásicas basadas en algoritmos de gradiente o de optimización sucesiva pueden llevar a soluciones subóptimas. Como posible alternativa se ha propuesto la aplicación de simulated annealing, una potente herramienta heurística y estocástica que permite hallar el diseño global óptimo incluso cuando el problema es no convexo.
Los errores en la información de canal disponible pueden empeorar el rendimiento del sistema si éstos no se tienen en cuenta explícitamente durante el diseño. La degradación del sistema MIMO-OFDM de un único usuario se ha estudiado en esta situación, obteniendo una expresión analítica de una cota superior de la máxima degradación relativa de la relación señal a ruido más interferencia.
El rendimiento se puede mejorar usando técnicas robustas que tengan en cuenta la presencia de dichos errores. Existen dos aproximaciones clásicas: las Bayesianas y las maximin. En las soluciones Bayesianas el problema se formula estadísticamente, donde el objetivo es optimizar el valor medio de una función de rendimiento promediada sobre la estadística del canal real condicionado a su estimación. Por otro lado, los diseños maximin se caracterizan por optimizar el peor rendimiento para cualquier posible error en la información del canal dentro de una cierta región de incertidumbre que modela el conocimiento imperfecto del mismo.
Se han mostrado dos ejemplos de diseños Bayesianos. Primero, una distribución de potencia en un sistema OFDM de una única antena que minimiza el valor medio de una cota superior de la tasa de error, y después un diseño de un transmisor multiantena con un banco de filtros que maximiza la relación señal a ruido media (SNR) o minimiza el error cuadrático medio.
Finalmente, se ha obtenido el diseño robusto maximin de un sistema MIMO de un único usuario donde en el transmisor se combinan un código bloque ortogonal espacio-tiempo, una distribución de potencia y un banco de conformadores correspondientes a los modos espaciales del canal estimado. La distribución de potencia se ha diseñado acorde a una región de incertidumbre para el error en la estimación de canal de manera que se maximiza la peor SNR en dicha región. Posteriormente, este diseño se ha extendido al caso de modulaciones adaptativas y multiportadora, mostrando que el rendimiento es mejor que para los códigos bloque otrogonales y la conformación no robusta.
This Ph.D. dissertation addresses the design of multi-antenna systems, where the most general case corresponds to a transmitter and a receiver with more than one antenna, i.e., a multiple-input-multiple-output (MIMO) channel. The main advantage is that they can provide a much better performance than single-antenna systems, both in terms of transmission quality and system capacity, i.e., number of users that can be served simultaneously.
The objective is to carry out a joint transmitter-receiver design, which depends directly on the quantity and the quality of the available channel state information (CSI). In this dissertation, the impact of the CSI on the design has been analyzed.
First, a single-user MIMO communication system has been designed assuming the use of the orthogonal frequency division multiplexing (OFDM) modulation and according to a perfect CSI at both sides. The proposed architecture is based on a joint beamforming approach per carrier. The optimum beamvectors have been calculated and several power allocation strategies among the subcarriers have been derived. These power allocation solutions have been shown to be asymptotically related to other classical designs but with a much lower computational load.
The previous design has been extended to multi-user communications, where the multi-antenna terminals in the scenario have a perfect CSI. The objective is the minimization of the total transmit power subject to maximum bit error rate (BER) constraints for each link. The mathematical optimization problem is non-convex and, therefore, classical solutions based on gradient search or alternate & maximize schemes may find a local suboptimum design. As a possible solution, the application of the simulated annealing technique has been proposed, a powerful stochastic optimization tool able to find the global optimum design even when the problem is non-convex.
The errors in the available CSI may decrease importantly the system performance if they are not taken into account explicitly in the design. This degradation has been studied for the single-user MIMO-OFDM system. An analytical expression of an upper-bound on the maximum relative signal to noise plus interference ratio degradation has been found.
The system performance can be improved when exploiting an imperfect CSI by using adequate robustness strategies. Two robust approaches have been proposed: the Bayesian and the maximin solutions. The Bayesian approach is a full statistical solution that optimizes the mean value of the performance function averaged over the statistics of the actual channel and the errors in the CSI. On the other hand, the maximin approach provides a design that optimizes the worst system performance for any possible error in a predefined uncertainty region.
Two simple examples of Bayesian designs have been provided. First, a power allocation has been derived for an OFDM system with one transmit and one receive antenna minimizing the mean value of an upper-bound on the BER. Afterwards, a design of a multi-antenna transmitter with a bank of filters and a single-antenna receiver has been proposed, whose objective is either the maximization of the mean signal to noise ratio (SNR) or the minimization of the mean square error.
Finally, a robust maximin design has been proposed for a single-user MIMO system, in which the transmitter is based on the combination of an orthogonal space time block code (OSTBC), a power allocation stage, and a set of beamformers coupling the transmission through the estimated channel eigenmodes. The power allocation has been found according to a channel estimate and an uncertainty region for the error in this estimate, so that the worst SNR for any error in the uncertainty region is maximized. This design has been then extended and applied to adaptive modulation schemes and multicarrier modulations, showing that the performance is much better than that achieved by a pure OSTBC solution or a non-robust beamforming scheme.
Zheng, Jun. "Design and analysis of MIMO systems with practical channel state information assumptions". Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2006. http://wwwlib.umi.com/cr/ucsd/fullcit?p3215292.
Pełny tekst źródłaTitle from first page of PDF file (viewed July 24, 2006). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references (p. 221-228).
Zhao, Peiyue. "Radio Resource Management Algorithms for D2D Communications With Limited Channel State Information". Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-177494.
Pełny tekst źródłaZhang, Xi. "Transceiver Design for Multiple Antenna Communication Systems with Imperfect Channel State Information". Doctoral thesis, Stockholm : Elektrotekniska system, Electrical Engineering, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4679.
Pełny tekst źródłaZhao, Bo [Verfasser]. "Limited Feedback of Channel State Information in Wireless Communication Systems / Bo Zhao". Düren : Shaker, 2021. http://d-nb.info/1240853483/34.
Pełny tekst źródłaMuralidhar, Aditya. "Multiple-Input Multiple Output System on a Spinning Vehicle with Unknown Channel State Information". International Foundation for Telemetering, 2012. http://hdl.handle.net/10150/581828.
Pełny tekst źródłaHuang, Jinliang. "Adaptation in multiple input multiple output systems with channel state information at transmitter". Licentiate thesis, Stockholm : Institutionen för elektronik, dator- och programvarusystem, Kungliga tekniska högskolan, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4443.
Pełny tekst źródłaLiu, Moyu. "HUMAN BIOMETRIC SIGNALS MONITORING BASED ON WIFI CHANNEL STATE INFORMATION USING DEEP LEARNING". Thesis, The University of Sydney, 2022. https://hdl.handle.net/2123/27463.
Pełny tekst źródłaSharma, Maneesha. "Effective channel state information (CSI) feedback for MIMO systems in wireless broadband communications". Thesis, Queensland University of Technology, 2014. https://eprints.qut.edu.au/71549/2/Maneesha_Sharma_Thesis.pdf.
Pełny tekst źródłaPayaró, Llisterri Miquel. "IMPACT OF CHANNEL STATE INFORMATION ON THE ANALYSIS AND DESIGN OF MULTIANTENNA COMMUNICATION SYSTEMS". Doctoral thesis, Universitat Politècnica de Catalunya, 2007. http://hdl.handle.net/10803/6900.
Pełny tekst źródłaEl disseny adequat de sistemes de comunicació amb múltiples antenes per satisfer aquesta demanda no només depèn de la funció de mèrit (o de la mètrica de rendiment) escollida, sinó que també es veu afectat per la quantitat i la qualitat de la informació de l'estat del canal que es troba disponible als extrems de la comunicació. Aquesta tesi tracta sobre l'anàlisi i el disseny d'arquitectures per sistemes de comunicació amb múltiples antenes i amb diferents nivells de quantitat i qualitat de la informació de l'estat del canal. La secció d'anàlisi es centra en l'estudi de la capacitat i les taxes de transmissió assolibles per aquests tipus de sistemes de comunicació i la part de disseny queda més encarada a la síntesi de sistemes de comunicació pràctics amb l'objectiu de maximitzar el rendiment d'acord amb la mètrica de rendiment escollida.
Primerament, l'atenció es centra en sistemes de comunicació amb múltiples antenes per a un únic usuari amb informació perfecte de l'estat del canal, que suposa una idealització dels sistemes pràctics que s'empren en la realitat. En aquest context, es revisen resultats de capacitat que són ben coneguts, i es caracteritza, a més, un transmissor lineal dissenyat per tal de maximitzar la fiabilitat de l'enllaç sense fils amb múltiples antenes. Addicionalment, s'apunten una sèrie d'analogies entre el disseny del transmissor lineal òptim i la teoria de construcció de constel.lacions de símbols.
En segon lloc, es roman en un escenari de comunicacions amb un únic usuari i es considera el cas on la informació sobre l'estat del canal és incompleta. En aquest cas, es presenta un anàlisi detallat sobre la capacitat a través de les formulacions ergòdica i composta (compound), les quals prenen significat depenent del model utilitzat per caracteritzar el canal. Mentres que en canals ràpidament variants la capacitat ergòdica és la mesura clau de les taxes de transmissió assolibles per qualsevol sistema de comunicació, en canals fixos o de variació lenta, és la capacitat composta, la que mesura la mínima taxa de transmissió assolible de forma sostinguda durant la transmissió del missatge.
Seguidament, es considera el cas on la informació disponible sobre l'estat del canal és imperfecta. Precisament, es discorre sobre un sistema de comunicació pràctic anomentat Precodificador Espacial de Tomlinson i Harashima i s'estudien les seves potencialitats en termes de taxes de transmissió assolibles. Gràcies a l'arquitectura versàtil del Precodificador Espacial de Tomlinson i Harashima l'esmentat estudi es duu a terme tant per escenaris amb un únic usuari com per escenaris amb múltiples usuaris. Per aquests dos casos, es presenta així doncs un disseny que és robust a les incerteses de la informació de l'estat del canal i que té per objectiu minimitzar les pèrdues de taxa de transmissió d'informació.
Finalment, restant en un escenari amb múltiples usuaris amb coneixement imperfecte de l'estat del canal, es presenta una arquitectura de transmissió que és robusta a les incerteses de la informació sobre l'estat del canal disponible tant en el transmisor com en el receptor. La variable per al disseny robust és la distribució de potència entre els símbols d'informació destinats a cada usuari, i el criteri d'optimització és minimitzar la potència total transmesa, tot garantint una determinada qualitat de servei per cada usuari i per qualsevol possible realització del canal que sigui compatible amb la informació disponible sobre l'estat del canal.
During the last decade, there has been a steady increase in the demand of high data rates that are to be supported by wireless communication applications. Among the different solutions that have been proposed by the research community to cope with this new demand, the utilization of multiple antennas arises as one of the best candidates due to the fact that it provides both an increase in reliability and also in information transmission rate. Although the use of multiple antennas at the receiver side dates back from the sixties, the full potential of multiple antennas at both communication ends has been both theoretically and practically recognized in the last few years.
The design of proper multi-antenna communication systems to satisfy the high data rates demand depends not only on the chosen figure of merit or performance metric, but also on the quantity and the quality of the channel state information that is available at the communication ends. In this dissertation we deal with the analysis and design of different architectures for multiple-antenna communication systems for various degrees of quality and quantity of channel state information. The analysis section is devoted to the study of capacity and achievable rates and the part that deals with design is aimed at the synthesis of practical communication systems that maximize a certain performance measure.
Firstly, we focus our attention on multiple antenna single-user communication systems with perfect channel state information, which is an idealization of actual practical systems. In this context, we review well known capacity results and deal with the practical characterization of a linear transmitter that is designed to maximize the reliability of the wireless multi-antenna link. Some analogies between the optimal linear transmitter design and the theory of constellation construction are also pointed out.
Secondly, we stay in a single-user scenario and we move onto the case where the channel state information is incomplete. In this case, a detailed capacity analysis is presented dealing with the ergodic and compound capacity formulations, which arise depending on the model utilized to characterize the channel. While in rapidly varying channels the ergodic capacity is a key measure of the rates that can be achieved by any communication system, in slow varying or fixed channels the compound capacity measures the minimum transmission rate that can be sustained during the transmission of the message.
Next, we shift to the case where the available channel state information is imperfect. Precisely, we deal with a practical communication system called spatial Tomlinson-Harashima precoder and study its achievable rate capabilities. Due to the versatile architecture of the spatial Tomlinson-Harashima precoder we are able to perform the study for the single and multi-user scenarios. For both cases, a design is presented which is robust to the uncertainties of the channel state information and which is aimed at maximizing the transmission rate.
Finally, staying in the multi-user scenario with imperfect channel state information, we present a transmission architecture that is robust to the uncertainties of the side information that is available at both the transmitter and the receiver. The robustness criterion is to minimize the transmitted power while guaranteeing a certain quality of service per user for every possible realization of the channel that is compatible with the available channel state information.
Buzuverov, Alexey [Verfasser], Anja [Akademischer Betreuer] Klein i Bruno [Akademischer Betreuer] Clerckx. "Multi-User Networks with Outdated Channel State Information / Alexey Buzuverov ; Anja Klein, Bruno Clerckx". Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2019. http://d-nb.info/1183911513/34.
Pełny tekst źródłaEngelmann, Sabrina. "Beamforming and Protection Strategies in Gaussian MISO Wiretap Systems with Partial Channel State Information". Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-172869.
Pełny tekst źródłaIn dieser Arbeit wird das Leistungsvermögen der Sicherheit auf der physikalischen Schicht anhand von zwei speziellen Systemmodellen untersucht. Im Detail werden Beamforming- und Absicherungsstrategien im gaußschen Multiple-Input Single-Output (MISO) Wiretap Channel (WTC) und dem gaußschen Two-hop Relay WTC mit mehreren Antennen am Sender und Empfänger studiert. In beiden Systemmodellen wird der Einfluss von partieller Kanalkenntnis zum Abhörer betrachtet und die so erreichbaren Sicherheitsraten mit denen verglichen, die bei voller Kanalkenntnis erreichbar sind. Für den MISO WTC kann gezeigt werden, dass für Kanäle mit schnellem Schwund der Beamforming-Vektor in Hinblick auf die ergodische Sicherheitsrate unter Berücksichtigung des Grades der Kanalkenntnis optimiert werden kann. Zudem kann durch die intelligente Verwendung von künstlichem Rauschen (Artificial Noise, AN) die ergodische Sicherheitsrate signifikant erhöht werden. Hierbei nimmt der Grad der Kanalkenntnis direkt Einfluss auf die Aufteilung der Leistung zwischen Daten- und AN-Signal am Sender sowie auch auf die Richtung, in der das AN-Signal gesendet wird. Zudem kann gezeigt werden, dass dieselben Beamforming- und Absicherungsstrategien ebenfalls die Sicherheitsausfallwahrscheinlichkeit für Kanäle mit langsamem Schwund minimieren. Im gaußschen Two-hop Relay WTC wird Information Leakage Neutralization (IN) als neuartige Absicherungsstrategie eingeführt. Diese Absicherungsstrategie erreicht nahezu dieselben instantanen Raten wie ein friedvolles System ohne Abhörer, wenn es bei voller Kanalkenntnis am Sender eingesetzt wird. Weiterhin sind durch die IN-Absicherungsstrategie höhere Raten erreichbar als durch den Einsatz von AN. Zusätzlich kann im Fall von voller Kanalkenntnis auf den Einsatz von Wiretap-Codes verzichtet werden. Auch im Fall partieller Kanalkenntnis, wo der Sender nur eine veraltete Schätzung des Kanals zwischen Relay und Abhörer besitzt, kann gezeigt werden, dass die IN-Absicherungsstrategie angewendet werden kann. Hierbei hängt es jedoch stark von den Kanalrealisierungen und dem Alter der Kanalschätzung ab, ob die IN- oder die AN-Absicherungsstrategie bessere Ergebnisse bringt und daher angewandt werden sollte
Ding, Minhua. "Multiple-input multiple-output wireless system designs with imperfect channel knowledge". Thesis, Kingston, Ont. : [s.n.], 2008. http://hdl.handle.net/1974/1335.
Pełny tekst źródłaTran, Tuyen X. "Achievable Rate and Capacity of Amplify-and-Forward Multi-Relay Networks with Channel State Information". University of Akron / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=akron1376743091.
Pełny tekst źródłaZhao, Bo [Verfasser], i Andreas [Akademischer Betreuer] Czylwik. "Limited Feedback of Channel State Information in Wireless Communication Systems / Bo Zhao ; Betreuer: Andreas Czylwik". Duisburg, 2021. http://d-nb.info/1239048777/34.
Pełny tekst źródłaCooper, Reginald Larenzo. "Sensing and Learning Channel State Information in a Dynamic Wireless Environment with Cognitive Radios and Networks". Research Showcase @ CMU, 2012. http://repository.cmu.edu/dissertations/211.
Pełny tekst źródłaYu, Zehao. "Towards location-awareness in next generation wireless networks : a new approach based on channel state information". Thesis, Massachusetts Institute of Technology, 2020. https://hdl.handle.net/1721.1/127117.
Pełny tekst źródłaCataloged from the official PDF of thesis.
Includes bibliographical references (pages 69-78).
Location-awareness in next generation wireless networks will be a key enabler for numerous emerging applications. Recently, a novel approach to localization based on soft information (SI), exploiting all positional information inherent in measurement and contextual data, has been proposed. This thesis further develops SI-based localization by establishing a new approach relying on channel state information (CSI) measurements. In particular, we design an efficient joint message-passing (MP) localization algorithm, which consists of two layers: the transformation layer and the estimation layer. The transformation layer extracts SI of the channel impulse response (CIR) from CSI measurements using a sparsity promoting prior model, which addresses the difficulty of unknown number of multipath in estimating the CIR. The estimation layer infers node positions based on the SI of the CIR using a delay-origin uncertainty model, which describes the conditional distribution of the delays in the CIR given node positions. Simulation results using QuaDriGa channel simulator show that our localization algorithm achieves decimeter-level localization accuracy for both Wi-Fi and mmWave signals, which outperforms conventional algorithms.
by Zehao Yu.
S.M.
S.M. Massachusetts Institute of Technology, Department of Aeronautics and Astronautics
Rey, Micolau Francesc. "Feedback-Channel and adaptative mimo coded-modulations". Doctoral thesis, Universitat Politècnica de Catalunya, 2006. http://hdl.handle.net/10803/6899.
Pełny tekst źródłaEn aquest context, aquesta tesi estudia dos problemes diferents però alhora estretament relacionats: el disseny d'un esquema pràctic de seguiment del canal en transmissió per canals variants en temps, i el disseny d'esquemes lineals de precodificació que siguin robustos a la incertesa del canal.
La primera part de la tesi proposa el disseny d'un esquema de seguiment de canal que, mitjançant un enllaç de retorn de baixa capacitat, proporcioni al transmissor una informació acurada sobre el seu estat. Històricament, aquest tipus d'esquemes han rebut fortes crítiques degut a la gran quantitat d'informació que és necessari transmetre des del receptor cap el transmissor. Aquesta tesi, doncs, posa especial èmfasi en el disseny d'aquest canal de retorn. La solució que es proposa, basada en el filtre de Kalman, utilitza un esquema que recorda al transmissor DPCM. Les variacions del canal són tractades mitjançant dos predictors lineals idèntics situats en el transmissor i en el receptor, i un canal de retorn que assisteix el transmissor amb l'error de predicció. L'interès d'aquest esquema diferencial és que permet seguir les variacions del canal amb només dos o quatre bits per coeficient complex, fins i tot en canals ràpidament variants.
La resta de la tesi cobreix el segon objectiu, l'estudi de diferents esquemes d'assignació de potències quan el coneixement del canal en transmissió no és perfecte. El problema es planteja per a un sistema MIMO OFDM com a formulació més general, incloent els casos d'una sola antena, de l'esquema beamforming i del canal multiplicatiu com a casos particulars.
Primerament s'ha plantejat l'optimització dels criteris de mínim error quadràtic mig (MMSE) i mínima BER sense codificar. La innovació en el treball presentat a la tesi, respecte a altres treballs que segueixen els mateixos criteris de disseny, ha estat la formulació Bayesiana del problema per al disseny dels algoritmes robustos.
La tesi continua amb el plantejament d'estratègies robustes d'assignació de potència destinades a minimitzar la BER codificada. Per aquesta tasca s'han utilitzat criteris de teoria de la informació. Possiblement una de les principals contribucions d'aquesta tesi ha estat el plantejament del cut-off rate com a paràmetre de disseny. Aquest criteri s'introdueix com alternativa a la capacitat de canal o a la informació mutual per al disseny del transmissor quan s'inclou codificació de canal.
La ultima part de la tesi proposa un interleaver adaptatiu de baixa complexitat que, utilitzant el coneixement del canal disponible en el transmissor, assigna estratègicament els bits no només per combatre les ràfegues d'errors, sinó també per lluitar contra els esvaïments que puguin presentar les diferents portadores del canal per a una realització concreta. El disseny d'aquest interleaver, anomenat "interleaver RCPC" està basat en els codis Rate-Compatible Punctured Convolutional Codes. Com s'il·lustra a partir del resultats numèrics, l'ús d'aquest interleaver millora les prestacions dels algoritmes quan es comparen amb les que s'obtindrien si s'utilitzes un interleaver de bloc o un interleaver pseudo-aleatori.
When the transmitter of a communication system disposes of some Channel State Information (CSI), it is possible to design linear precoders that optimally allocate the power inducing high gains either in terms of capacity or in terms of reliable communications. In practical scenarios, this channel knowledge is not perfect and thus the transmitted signal suffers from the mismatch between the CSI at the transmitter and the real channel.
In that context, this thesis deals with two different, but related, topics: the design of a feasible transmitter channel tracker for time varying channels, and the design of optimal linear precoders robust to imperfect channel estimates.
The first part of the thesis proposes the design of a channel tracker that provides an accurate CSI at the transmitter by means of a low capacity feedback link. Historically, those schemes have been criticized because of the large amount of information to be transmitted from the receiver to the transmitter. This thesis focuses, thus, the attention in an accurate design of the return link. The proposed solution is based on the Kalman filter and follows a scheme that reminds the well known DPCM transmitter. The channel variability is processed by two identical linear predictors located at the transmitter and at the receiver, and a feedback link that assists the transmitter with the prediction error. The interest of this differential scheme is that allows to track the channel variations with only two or four bits per complex channel coefficient even in fast time-varying channels.
The rest of the thesis covers the second topic, studying different robust power allocation algorithms when the CSI is not perfectly known at the transmitter. For the sake of generality, the problem is formulated for the general MIMO OFDM case, encompassing the single antenna transmission, the beamforming schemes and the frequency-flat fading channels as particular cases.
First, the minimum MSE and the minimum uncoded BER parameters are chosen to be optimized, evaluating the performance of the algorithms in terms of uncoded BER. The basic novelty with respect to previous works that considers the same strategies of design is the proposal of a Bayesian approach for the design of the robust algorithms.
Next the study is extended by proposing robust power allocation strategies focused on the minimization of the coded BER. For this purpose, information-theoretic criteria are used. Probably, one of the main contributions in the thesis is the proposal of the cut-off rate as a parameter of design whose maximization is directly related to the coded BER. This criterion is introduced as an alternative to the channel capacity and the mutual information for the design of optimal transceivers in the presence of any channel coding stage.
The last part of the thesis proposes a low complexity adaptive interleaver that, making use of the CSI available at the transmitter, reallocates the bits not only to combat the bursty channel errors but also to combat the specific distribution of the faded subcarriers as a function of the channel response. The design of this interleaver, named as "RCPC interleaver", is based on the Rate-Compatible Punctured Convolutional Codes. As shown by numerical results, the use of this interleaver improves the performance of the algorithms when they are compared with the classical block interleavers and pseudo-random interleavers.
Duong, Duc Van. "Analysis and optimization of pilot-aided adaptive coded modulation under noisy channel state information and antenna diversity". Doctoral thesis, Norwegian University of Science and Technology, Faculty of Information Technology, Mathematics and Electrical Engineering, 2006. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-987.
Pełny tekst źródłaThe thesis is largely built on a collection of published and submitted papers where the main focus is to analyze and optimize single-carrier adaptive coded modulation systems with and without antenna diversity. Multidimensional trellis codes are used as component codes. The majority of the analysis is done with both estimation and prediction errors being incorporated. Both channel estimation and prediction are performed using a pilot-symbol-assisted modulation scheme. Thus, known pilot symbols (overhead information) must be transmitted; which consumes power and also degrades system spectral efficiency. Both power consumption and pilot insertion frequency are optimized such that they are kept at necessary values to maximize system throughput without sacrificing the error rate performance. The results show that efficient and reliable system performance can be achieved over a wide range of the considered average channel quality. Going from a single-input single-output system to both spatially uncorrelated and correlated single-input multiple-ouput (SIMO) systems, and further to an uncorrelated multiple-input multiple-output (MIMO) diversity system, is the evolution of the thesis. In the SIMO case, maximum ratio combining is used to combine the incoming signals, whereas the signals are space-time combined in the MIMO diversity system. The multiple-input single-output system comes out as a special case of a MIMO system. Besides the spatially uncorrelated antenna array, the effect of spatial correlation is also considered in the SIMO case. In this case, only prediction error is considered and channel estimation is assumed to be perfect. At first, the impact of spatial correlation in a predicted system originally designed to operate on uncorrelated channels is quanitifed. Then, a maximum a posteriori (MAP)-optimal “space-time predictor” is derived to take spatial correlation into account. As expected, the results show that the throughput is still lower than the uncorrelated system, but the degradation is decreased when the MAP-optimal space-time predictor is used. Thus, by exploiting the correlation properly, the degradation can be reduced. By numerical examples, we demonstrate the potential effect of limiting the predictor complexity, of fixing the pilot spacing, as well as of assuming perfect estimation. The two first simplifications imply lower system complexity and feedback rate, whereas the last assumption is usually made to ease the mathematical analysis. The numerical examples indicate that all the simplifications can be done without serious impact on the predicted system performance.
Chiang, Hsiao-Lan [Verfasser], Gerhard [Gutachter] Fettweis i Volker [Gutachter] Kühn. "Millimeter-Wave Hybrid Beamforming Based on Implicit Channel State Information / Hsiao-Lan Chiang ; Gutachter: Gerhard Fettweis, Volker Kühn". Dresden : Technische Universität Dresden, 2019. http://d-nb.info/1230578064/34.
Pełny tekst źródłaXie, Yongzhe. "On adaptive transmission, signal detection and channel estimation for multiple antenna systems". Diss., Texas A&M University, 2004. http://hdl.handle.net/1969.1/1058.
Pełny tekst źródłaGiese, Jochen. "Constellation Design under Channel Uncertainty". Doctoral thesis, KTH, School of Electrical Engineering (EES), 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-454.
Pełny tekst źródłaThe topic of this thesis is signaling design for data transmission through wireless channels between a transmitter and a receiver that can both be equipped with one or more antennas. In particular, the focus is on channels where the propagation coefficients between each transmitter--receiver antenna pair are only partially known or completetly unknown to the receiver and unknown to the transmitter.
A standard signal design approach for this scenario is based on separate training for the acquisition of channel knowledge at the receiver and subsequent error-control coding for data detection over channels that are known or at least approximately known at the receiver. If the number of parameters to estimate in the acquisition phase is high as, e.g., in a frequency-selective multiple-input multiple-output channel, the required amount of training symbols can be substantial. It is therefore of interest to study signaling schemes that minimize the overhead of training or avoid a training sequence altogether.
Several approaches for the design of such schemes are considered in this thesis. Two different design methods are investigated based on a signal representation in the time domain. In the first approach, the symbol alphabet is preselected, the design problem is formulated as an integer optimization problem and solutions are found using simulated annealing. The second design method is targeted towards general complex-valued signaling and applies a constrained gradient-search algorithm. Both approaches result in signaling schemes with excellent detection performance, albeit at the cost of significant complexity requirements.
A third approach is based on a signal representation in the frequency domain. A low-complexity signaling scheme performing differential space--frequency modulation and detection is described, analyzed in detail and evaluated by simulation examples.
The mentioned design approaches assumed that the receiver has no knowledge about the value of the channel coefficients. However, we also investigate a scenario where the receiver has access to an estimate of the channel coefficients with known error statistics. In the case of a frequency-flat fading channel, a design criterion allowing for a smooth transition between the corresponding criteria for known and unknown channel is derived and used to design signaling schemes matched to the quality of the channel estimate. In particular, a constellation design is proposed that offers a high level of flexibility to accomodate various levels of channel knowledge at the receiver.
Juntti, J. (Juhani). "Performance analysis of suboptimal soft decision DS/BPSK receivers in pulsed noise and CW jamming utilizing jammer state information". Doctoral thesis, University of Oulu, 2004. http://urn.fi/urn:isbn:9514273869.
Pełny tekst źródłaChari, Shreya Krishnama. "Link blockage modelling for channel state prediction in high-frequencies using deep learning". Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-287458.
Pełny tekst źródłaMed tillgängligheten till generöst spektrum och utveckling av antennmatriser med hög förstärkning har trådlös kommunikation i högre frekvensband som ger multi-gigabit kortdistans trådlös åtkomst blivit verklighet. Riktningsantennerna har visat sig minska förluster på grund av störande signaler men är fortfarande utsatta för blockeringshändelser. Dessa händelser hindrar den övergripande användaranslutningen och genomströmningen. En mobil blockerare såsom ett fordon i rörelse förstärker blockeringseffekten. Modellering av blockeringseffekter hjälper till att förstå dessa händelser på djupet och bibehålla användaranslutningen. Denna avhandling föreslår användning av en fyrstatskanalmodell för att beskriva blockeringshändelser i högfrekvent kommunikation. Två djupinlärningsarkitekturer designas och utvärderas för två möjliga uppgifter, förutsägelsen av signalstyrkan och klassificeringen av kanalstatusen. Utvärderingarna baserade på simulerade spår visar hög noggrannhet och föreslår att de föreslagna modellerna har potential att utökas för distribution i verkliga system.
Ngo, Minh Hanh. "Cross-layer adaptive transmission scheduling in wireless networks". Thesis, University of British Columbia, 2007. http://hdl.handle.net/2429/432.
Pełny tekst źródłaBothenna, Hasitha Imantha. "Approximation of Information Rates in Non-Coherent MISO wireless channels with finite input signals". University of Akron / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=akron1516369758012866.
Pełny tekst źródłaGerman, Gus Ryan. "A Ray-Based Investigation of the Statistical Characteristics and Efficient Representation of Multi-Antenna Communication Channels". BYU ScholarsArchive, 2004. https://scholarsarchive.byu.edu/etd/145.
Pełny tekst źródłaZhang, Lili. "Interference Channel with State Information". Thesis, 2012. http://hdl.handle.net/1969.1/ETD-TAMU-2012-08-11427.
Pełny tekst źródłaAubry, Augusto. "MIMO Multiple Access Channels with Partial Channel State Information". Tesi di dottorato, 2010. http://www.fedoa.unina.it/8135/1/Aubry_Augusto_23.pdf.
Pełny tekst źródłaPerera, Ranjana. "On capacity of fading channels with no channel state information". Phd thesis, 2006. http://hdl.handle.net/1885/10354.
Pełny tekst źródłaHuang, Kaibin. "MIMO networking with imperfect channel state information". Thesis, 2008. http://hdl.handle.net/2152/4007.
Pełny tekst źródłatext
CHEN, LI-YONG, i 陳力永. "Compressing Channel State Feedback Information Using Autoencoder". Thesis, 2019. http://ndltd.ncl.edu.tw/handle/996z7t.
Pełny tekst źródła國立臺北科技大學
電子工程系
107
Channel State Information (CSI) refers to the property of the wireless communication link. CSI can be used to know the effect of the overall fading procedure of the signal from the transmitter to the receiver. In the traditional wireless communication, CSI obtained by the channel estimation is used to restore the distortion of the signal amplitude and phase caused by the channel fading. Nowadays, the application of CSI is becoming more and more diverse, such as: communication scenario identification, user behavior identification, adaptive transmission, channel selection, etc. However, if CSI is directly transmitted back to the base station, a large amount of transmission resources will be consumed. Therefore, how to efficiently transmit CSI to the base station is an important issue. This paper will use deep learning autoencoder to effectively compress and restore the CSI. To verify the effects of autoencoder, this paper use real measurement data from the Software Defined Radio (SDR) device and simulation data from MATLAB, and we will use four different channel state feedback information autoencoder. The result shows that the channel state feedback information can be ffectively compressed and restored by autoencoder. The NMSE of the LOS scenario is as low as 0.0027. The result also shows that the same autoencoder can be used by multiple points. Besides, compared to codebook,the signal strength autoencoder’s NMSE is smaller ,and it can save 30% of the transmission data.
Khoshnevis, Behrouz. "Multiple-antenna Communications with Limited Channel State Information". Thesis, 2011. http://hdl.handle.net/1807/30036.
Pełny tekst źródłaYazdan, Panah Ali. "Relay-aided communications with partial channel state information". Thesis, 2011. http://hdl.handle.net/2152/ETD-UT-2011-08-4264.
Pełny tekst źródłatext
Buzuverov, Alexey. "Multi-User Networks with Outdated Channel State Information". Phd thesis, 2019. http://tuprints.ulb.tu-darmstadt.de/8571/1/2019_01_21_Buzuverov_Alexey.pdf.
Pełny tekst źródłaLi-YuanChen i 陳立遠. "Channel State Information (CSI) Reductionfor Cooperative OFDM Systems". Thesis, 2016. http://ndltd.ncl.edu.tw/handle/z43kje.
Pełny tekst źródła國立成功大學
電腦與通信工程研究所
104
In recent years, cooperative communications have received much attention. The concept of cooperative communications is to let un-used mobile units help the transmission of other users. Through the neighbor nodes, the transmitted signal can be relayed to the destination. Cooperative communications can reinforce the point-to-point transmission channel. Based on the cooperative communications, we attain a scenario that is like there are several transmit antennas at the transmitter, and this achieves the effect of multiple-input multiple-output (MIMO) system. In fact, the transmitter needs the forward channel state information (CSI) to improve the performance of system. Sometimes, the transmitter needs to estimate the channel responses (CRs) and/or channel amplitude, and forward these CRs to the receiver, and this increases the forward load. In order to efficiently forward the CSI, we propose an efficient method that forward the estimated channel responses (CRs) to the receiver based on the Karhunen-Loève Expansion (KLE). The coefficients of the KLE are used as the parameters for rebuilding the CRs. The number of coefficients of the KLE is much fewer than the size of the original block of CRs, and the KLE leads to efficient compression. These coefficients are Gaussian distribution and nearly uncorrelated. To efficiently forward the coefficients for the cooperative OFDM system, we use the Gaussian quantization (GQ) to reduce the quantization error. The simulation results show that the proposed algorithms can attain good error performance for the cooperative OFDM systems with low forward load in time-varying and frequency-selective channels.
Liu, Chi-Tang, i 劉啟堂. "Exploiting Decentralized Channel State Information for Slotted ALOHA". Thesis, 2011. http://ndltd.ncl.edu.tw/handle/56388979156402692810.
Pełny tekst źródła國立臺灣大學
電信工程學研究所
99
Conventional Slotted ALOHA is a random access protocol designed for collision channels. In this thesis, we consider a cross layer design that exploits decentralized channel state information (D-CSI) for the Medium Access Control (MAC) layer protocol such as slotted ALOHA under the SINR capture model. In view of the inferior performance of the threshold based transmission, we first propose a single-region based channel aware ALOHA strategy that can reduce the multiple access interference (MAI). The system throughput is analyzed and optimized for a wireless network with homogeneous fading. We then propose a two-region extension. Both strategies have a significant gain over other common used protocols. We conclude that the Single-Region strategy is preferable when the SINR capture ratio is smaller than one and the Two-Region strategy is better when the SINR capture ratio is large than one.