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Baby, Johnson. "LTE UPLINK MODELLING AND ANALYSIS OF CARRIER FREQUENCY OFFSET ON UPLINK TRANSMISSION INTERFERENCE". Thesis, Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-24015.
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This master thesis analyzes the effect of Carrier Frequency Offsets (CFO) on LTEuplink transmission, which is the main cause of ICI (Inter Carrier Interference) andMAI (Multiuser Access Interference). A model of the LTE uplink is required toconduct the study and is implemented in MATLAB, in compliance with 3GPPspecifications. The model can generate uplink signal as generated by the UE, (UserEquipment) and it supports multiple channel bandwidths described by the 3GPP.The channel estimation is done with the help of block type pilots. The model is usedto simulate the experimental conditions. The presence of CFO results in poor systemperformance. Therefore, many algorithms have been proposed for the CFOcancellation such as Successive Interference Cancellation (SIC), Parallel InterferenceCancellation (PIC) and Inverse Interference Matrix Cancellation. As the topic is verybroad, I investigate the performance of Inverse Interference Matrix Cancellationalgorithm. Compared with the other CFO cancellation algorithms this algorithm candirectly estimate the interference components from the inverse pilot matrix, thusthere is no need for CFO estimation. Simulation results show that the algorithm isvery effective in the presence of CFO. The channel estimation technique used is theLeast Square (LS) method and frequency selective channel is used for simulation.Performance graphs are plotted in terms of BER (Bit Error Rate) against differentvalues of SNR (Signal to Noise Ratio).
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Prasai, Sandesh. "Access control of NUTS uplink". Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for telematikk, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-19209.
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Mehari, Tariku Temesgen. "Frequency Hopping in LTE Uplink". Thesis, Blekinge Tekniska Högskola, Avdelningen för telekommunikationssystem, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-4232.
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In the 3GPP LTE, different radio resource management (RRM) techniques have been proposed in order to improve the uplink performance. Frequency hopping is one of the techniques that can be used to improve the uplink performance by providing frequency diversity and interference averaging. The hopping can be between subframes (inter-subframe) or within a subframe (intra-subframe). 3GPP specifies two types of frequency hopping for the LTE uplink, hopping based on explicit hopping information in the scheduling grant and sub-band based hopping according to cell-specific hopping and mirroring patterns. In this master’s thesis, theoretical discussion on the frequency hopping schemes is carried out followed by dynamic simulations in order to evaluate the performance gain of frequency hopping. Based on the theoretical analysis, the second type of hopping is selected for detailed study. As a baseline for comparison, dynamic frequency domain scheduling with random frequency resource allocation has been used. Single cell and multi-cell scenarios have been simulated with VoIP traffic model using user satisfaction as a performance metric. The simulation results show that frequency hopping improves the uplink performance by providing frequency diversity in the single cell scenario and both frequency diversity and interference averaging in the multi-cell scenario. The gains in using the hopping schemes were reflected as VoIP capacity (the number of satisfied users) improvement. In this study, the performance of the selected hopping schemes under different hopping parameters is also evaluated.ttma07@student.bth.se tariku.temesgen.mehari@ericsson.com
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Ho, Kenneth T. "Uplink channel estimation in WiMAX". College Park, Md. : University of Maryland, 2008. http://hdl.handle.net/1903/8214.
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Thesis (M.S.) -- University of Maryland, College Park, 2008.Thesis research directed by: Dept. of Electrical and Computer Engineering. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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Persson, Markus. "Uplink TDMA Potential in WCDMA Systems". Thesis, Linköping University, Department of Electrical Engineering, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-11399.
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The evolvement of the uplink in the third generation mobile telecommunication system is an ongoing process. The Enhanced Uplink (EUL) concept is being developed to meet the expected need from more advanced services, like video streaming and mobile broadband. One idea for further improvement in the EUL concept is to introduce Time Division Multiple Access (TDMA), which is studied in this master thesis.
The master thesis assignment is to study the consequences of introducing TDMA in EUL. The goal has been to identify the gains and problems, and how they can be handled. A derived theoretical framework and system simulations, using a radio network simulator, are used.
The overall conclusion is that there is a potentially large gain with an introduction of TDMA in EUL. Simulations in favorable conditions have shown that the system throughput can increase by 100% when there are only User Equipment (UE) that are using EUL in the system and by 50% when there is a mix of speech and EUL UE’s. When using TDMA the uplink load also shows improvements, the mean is generally higher but the variance is generally smaller.
Due to major differences in experienced interference between passive and active UE’s, the signal quality will vary a lot. The big variation in signal quality is identified as the main problem with introducing TDMA in EUL. It is shown that this problem can generate extreme high uplink load, which have a negative impact both on the resource efficiency and the coverage.
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Brännström, Nils. "Voice-over-IP over Enhanced Uplink". Thesis, Linköping University, Department of Electrical Engineering, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-8479.
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The traditional voice service in mobile networks is an important service that mobile users expect high quality from. With the convergence of mobile networks towards an all-IP network, an IP-based speech service becomes important which is referred to as Voice-over-IP (VoIP). The traditional voice service is highly optimized and a VoIP service must therefore fulfil strict quality requirements to provide the same speech service quality. The air interface technology, WCDMA, which is used in third generation communication systems in Europe is constantly developed. An improved concept for the mobile-to-network transmission, called the Enhanced Uplink (EUL) provides for higher uplink capacity for packet data services. It also includes features that may provide a sufficient VoIP service quality in mobile networks, when considering the uplink transmission.
The purpose of this thesis is to evaluate the VoIP capacity over EUL and identify crucial aspects of radio resource management in order to increase the capacity. This is done through dynamic system simulations, using a realistic VoIP traffic model. The VoIP capacity is also estimated by a derived theoretical framework.\newline
It is shown by simulation results and theoretical estimations, that power control is a vital mechanism in order to increase the capacity. Simulation results indicate that a VoIP over EUL capacity of 65\% of the traditional voice service capacity may be reached. The results also indicate that to improve the capacity for larger cells, the allowed VoIP packet delay must be increased.
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Ahmed, Mohsin Niaz. "LTE Uplink Modeling and Channel Estimation". Thesis, Linköpings universitet, Datorteknik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-69571.
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This master thesis investigates the uplink transmition from User Equipment (UE) to base station in LET (Long Term Evolution) and channel estimation using pilot symbols with parameter defined in 3GPP (3rd Generation Partnership Project) specifications. The purpose of the thesis was to implement a simulator which can generate uplink signal as it is generated by UE. The Third Generation (3G) mobile system was given the name LTE. This thesis focus on the uplink of LTE where single carrier frequency division multiple access (SC-FDMA) is utilized as a multiple access technique. The advantage over the orthogonal frequency division multiple access (OFDMA), which is used in downlink is to get better peak power characteristics. Because in uplink communication better peak power characteristic is necessary for better power efficiency in mobile terminals. To access the performance of uplink transmition realistic channel model for wireless communication system is essential. Channel models used are proposed by International Telecommunication Union (ITU) and the correct knowledge of these models is important for testing, optimization and performance improvements of signal processing algorithms. The channel estimation techniques used are Least Square (LS) and Least Minimum Mean Square Error (LMMSE) for different channel models. Performance of these algorithms has been measured in term of Bit Error Rate (BER) and Signal to Noise Ratio (SNR).
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Di, Shuang. "USB Attached Network Performance : Uplink Performance". Thesis, KTH, Kommunikationssystem, CoS, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-91529.
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More and more people all over the world are using a USB modem to connect to the Internet. This is especially true in Sweden- which has the highest 3G coverage in Europe. Comparable to fixed broadband access, using a 3G USB modem is a wonderful experience for the customer. Increasingly, anywhere we can use our cellular phone is a place that we are able to access the Internet, even if we are traveling in a train, walking in a park, or sitting on the beach. This makes working on the move much easier. However, customers do not know if the network throughput, delay, and the cost of connectivity match their needs. Additionally, there is also the question of the time to connect to the network when there has not been some traffic for a period of time. However, the throughput, delay, and "time to connect" when using such a modem to connect to a wireless network depend on several factors. In this thesis we will examine these factors. More specifically, the thesis will analyze in detail the effects of using a USB attached network interface, in order to gain greater understanding of such an interface’s network performance. We have chosen to focus on the uplink, as it was expected to have a low throughput and it has not had as much attention as the downlink performance.Fler och fler människor över hela världen använder ett USB-modem för att ansluta tillInternet. Detta gäller i synnerhet i Sverige, som har den största 3G-täckning i Europa.Jämförbar med fast bredband, med hjälp av ett 3G USB-modemet är en underbar upplevelseför kunden. Allt var som helst vi kan använda vår mobiltelefon är en plats som vi hartillgång till Internet, även om vi färdas i ett tåg, promenad i en park, eller sitter på stranden.Detta gör att arbeta på resande fot mycket enklare. Men kunderna inte vet om nätetgenomströmning, fördröjning, och kostnaden för anslutning passar deras behov. Dessutomfinns det också en fråga om tid att ansluta till nätverket när det inte har funnits några trafikför en tid. Men den genomströmning, fördröjning och "tid för att ansluta" när du använderett modem för att ansluta till ett trådlöst nätverk beror på flera faktorer. I denna avhandlingkommer vi att undersöka dessa faktorer. Mer specifikt avhandlingen analyserar i detaljeffekterna av att använda en USB bifogade nätverkskort, för att få större förståelse för ettsådant gränssnitt nätverk prestanda. Vi har valt att fokusera på upplänk, eftersom detförväntas ha låg kapacitet och det har inte fått lika mycket uppmärksamhet som denerlänkning prestanda.
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Manssour, Jawad. "Network Coding in Uplink Cellular Systems". Thesis, KTH, Kommunikationssystem, CoS, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-48936.
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Ever since its introduction, network coding has attracted a lot of interest from the research community. This interest is a result of two main factors: the simplicity of application of network coding and the possibility to apply it to a plethora of applications. Research in network coding started on wired networks for different types of traffic, mainly focusing on code design, content distribution and network security. However, researchers soon came to realize that the inherent properties of the wireless medium render it a fertile ground for the application of network coding. This has resulted in tremendous research efforts on wireless applications of network coding for wireless systems, both academically and industrially, with the majority of these works targeting bidirectional traffic scenarios. In this work, we focus on practical implementation issues for network coding when applied to uplink cellular traffic. We provide our own relaying scheme based on decode-and-forward relays and network coding with a specially designed method of decoding at the receiver. We complement this method with user grouping, relay selection diversity and time division among the transmitting nodes in order to achieve the gains promised by network coding in terms of throughput increase, while halving the power usage at the relay nodes. We show that these complements are necessary in order to translate the decrease in the number of transmissions offered by network coding into capacity gains; otherwise, random application of network coding would provide a worse performance compared to direct transmission or decode-and-forward relaying.
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Goran, Alan. "Reinforcement Learning for Uplink Power Control". Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-246043.
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Uplink power control is a resource management functionthat controls the signal’s transmit power from a userdevice, i.e. mobile phone, to a base-station tower. It isused to maximize the data-rates while reducing the generatedinterference.Reinforcement learning is a powerful learning techniquethat has the capability not only to teach an artificial agenthow to act, but also to create the possibility for the agentto learn through its own experiences by interacting with anenvironment.In this thesis we have applied reinforcement learningon uplink power control, enabling an intelligent softwareagent to dynamically adjust the user devices’ transmit powers.The agent learns to find suitable transmit power levelsfor the user devices by choosing a value for the closed-loopcorrection signal in uplink. The purpose is to investigatewhether or not reinforcement learning can improve the uplinkpower control in the new 5G communication system.The problem was formulated as a multi-armed banditat first, and then extended to a contextual bandit. We implementedthree different reinforcement learning algorithmsfor the agent to solve the problem. The performance ofthe agent using each of the three algorithms was evaluatedby comparing the performance of the uplink power controlwith and without the agent. With this approach we coulddiscover whether the agent is improving the performanceor not. From simulations, it was found out that the agentis in fact able to find a value for the correction signal thatimproves the data-rate, or throughput measured in Mbps,of the user devices average connections. However, it wasalso found that the agent does not have a significant contributionregarding the interference.Uplink effektstyrning är en funktion för resurshanteringsom styr signalens sändningseffekt från en användaranordning,det vill säga från en mobiltelefon, till ett bas-stationstorn.Det används för att maximera datahastigheterna samtidigtsom den genererade interferensen reduceras.Förstärkningsinlärning är en kraftfull inlärningsteknik.Den har förmågan att inte bara lära en artificiell agent hurman agerar utan också skapa möjligheten för agenten attlära sig själv, genom att samspela med en miljö och samlaegna erfarenheter.I detta examensarbete har vi tillämpat förstärkningsinlärningpå uplink effektstyrning, vilket möjliggör för enintelligent mjukvaruagent att dynamiskt anpassa effektenpå sändningssignalerna hos användarens enheter. Agentenlär sig att hitta lämpliga sändningseffekter för enheternagenom att välja ett värde för korrigeringssignalen med slutenslinga i uplinken. Syftet är att undersöka huruvida förstärkningsinlärningkan förbättra uplink effektstyrningen idet nya 5G-kommunikationssystemet.Problemet formulerades som en Multi-Armed banditförst och utvidgades sedan till en Contextual bandit. Viimplementerade tre olika förstärkningsinlärning algoritmerför agenten att lösa problemet. Utförandet av agenten medanvändning av var och en av de tre algoritmerna utvärderadesgenom att jämföra prestanda för uplink effektstyrningenmed och utan agenten. Med detta tillvägagångssättkunde vi upptäcka om agenten förbättrar prestanda eller inte.Från våra simuleringar upptäcktes att agenten faktisktkan hitta ett värde för korrigeringssignalen som förbättrardatahastigheten, genomflödet mätt i Mbps, av genomsnittligaanslutningar för användarenheterna. Det har däremotockså visat sig att agenten inte har ett betydande bidragavseende interferensstörningarna.
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Lindén, Erik. "Iterative Channel Estimation in LTE Uplink". Thesis, KTH, Kommunikationsteori, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-147128.
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An algorithm for iterative channel estimation using soft feedback for LTE uplink is proposed. The algorithm has low complexity compared to MMSE estimation and does not require knowledge of the channel statistics. A simple polynomial model is used for noise suppression across OFDM symbols and a DCT-based filter is used for noise suppression across subcarriers. The algorithm has been tested on several channel models and has been shown to provide a gain of about 0:5 dB with two estimation stages, compared to the no-feedback case. Further, the algorithm has been applied to a MIMO case. A comparison has been made between the proposed algorithm and turbo equalization.En algoritm for iterativ kanalestimering i LTE-upplank foreslas. Algoritmen harlag komplexitet jamfort med MMSE-estimering. En enkel polynomiell modellanvands for att undertrycka brus over OFDM-symboler och ett DCT-baseratlter anvands for att undertrycka brus over sub-barvagor.Algoritmen har testats med era kanalmodeller och visats ge en vinst pa cirka0:5 dB med tva estimeringsitrationer, jamfort med en icke-iterativ mottagare.Algoritmen har ocksa applicerats till en MIMO-situation.En jamforelse mellan den foreslagna algoritmen och turboutjamning hargjorts.
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Suárez, Real Alberto. "Resource allocation for multiuser uplink systems". Nice, 2010. http://www.theses.fr/2010NICE4077.
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Dans cette thèse nous étudierons l’allocation de puissance optimale pour des systèmes de communication multi utilisateur en lien ascendant. L’ordre de décodage et l’allocation de puissance optimaux pour minimiser la consommation totale de puissance sont déterminés lorsque les utilisateurs ont des contraintes de débit et que la suppression d’interférence est utilisée dans la station de base. De plus, nous chercherons à déterminer dans quelles conditions il est possible de faire une allocation distribuée en ne se basant que sur les connaissances statistiques du système. Par la suite nous considérerons les systèmes a entrées multiples sorties multiples, afin d’obtenir les matrices de précodage optimales pour que chaque utilisateur maximise son taux de transmission ergodique avec la seule connaissance des statistiques des canaux. Les bénéfices de l’utilisation d’un signal de coordination et de décodages successifs sont analysés. Ensuite, nous considérerons un scénario dans lequel les terminaux mobiles ont la possibilité de se connecter simultanément à plusieurs stations de base en utilisant des bandes de fréquence non superposées. L’allocation de puissance optimale est dérivée pour différents types de récepteurs et un algorithme itératif est proposé pour obtenir l’allocation optimale. Finalement, nous considérerons les contrôles d’accès au canal décentralisé entre utilisateurs choisis aléatoirement parmi une population nombreuse, avec de nombreuses interactions entre paires d’utilisateurs où les utilisateurs sont en concurrence pour une opportunité d’accès. Le choix du niveau de puissance est fait par chaque utilisateur, et nous analyserons à la fois les scénarios d’équipe et non coopératifsIn this thesis we study the subject of resource allocation for uplink communication systems. When users have target rate constraints and interference cancelation is used at the base station we provide the optimal decoding order and power allocation in order to minimize the power consumption. In addition conditions are derived under which the allocation can be done in a distributed way, with only some knowledge of the statistics of the system. We then proceed to consider multiple-input multiple-output (MIMO) systems, and obtain the optimal precoding matrices such that each user maximizes its own ergodic transmission rate from the sole knowledge of the overall channel statistics. The benefits of using a coordination signal and successive decoding are analyzed. Next, a scenario in which mobile terminals can be simultaneously connected to several base stations, using non-overlapping frequency bands is considered. The optimal power allocation in terms of sum rate is derived for different receiver types and an iterative algorithm proposed to achieve the optimal allocation. Finally, we consider decentralized medium-access control in which many pairwise interactions, where users compete for a medium access opportunity, occur between randomly selected users that belong to a large population. The choice of power level is done by each user, and both team and noncooperative scenarios are analyzed
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Yao, Xuefeng. "Performance analysis of massive MIMO networks". Thesis, The University of Sydney, 2018. http://hdl.handle.net/2123/18847.
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Mobile data tra_c is predicted to grow 1000x from now until 2030 [1, 2], and dense small cell networks (SCNs) and massive multiple input multiple output (mMIMO) are considered the major pilar technologies to meet this ever-increasing capacity demand in the years to come. Dense SCNs which is comprised of picocells, femtocells, metrocells, etc are considered to be one of the main approaches to signi_cantly increase the network capacity and meet the capacity demand in 5G network. Indeed, the orthogonal deployment of SCNs with existing macrocells has already been applied as one solution in 4thgeneration and 5-th generation networks by the 3rd Generation Partnership Project (3GPP). SCNs are able to enhance the network capacity because of the high spatial reuse, eg, network capacity could potentially grow linearly with the number of small cells. In this thesis, We _rst discuss the performance analysis of dense SCNs using stochastic geometry. On the other hand, massive multiple input and multiple output (mMIMO) is also considered as one of the most important candidate technologies to meet the everincreasing capacity demand in the years to come [2]. By exploiting its many antennas and thus degrees of freedom in the spatial domain, mMIMO can increase the per-cell and the area spectral e_ciency (ASE) through spatial multiplexing. The larger the number of antennas, the larger the number of degrees of freedom, and thus the more multiplexing opportunities. However, when a time division duplex (TDD) system is considered, the performance of mMIMO may be limited by inaccurate channel state information (CSI). Pilot contamination is one of the major bottlenecks, and occurs when the same set of uplink (UL) pilot sequences is reused across neighbouring cells. Other channel estimation impairments also play a role. In this thesis, we _rstly introduce the performance evaluation of dense SCNs using stochastic. Previously, performance analysis of cellular networks is under the assumption that the base stations(BSs) and user equipments(UEs) are placed randomly or deterministically. The models under these assumptions are highly idealized. Stochastic geometry is introduced as a very tractable approach to analyze the networks performance of cellular networks. However, it is notable that the results are base on considerable simpli_cation on network scenarios. In this thesis, more realworld features of SCNs are considered. The BSs are activated when there is UE connected to them which is called Idle Mode. moreover, Both piece-wise path loss function and probabilistic line-of-sight (LoS) and non-line-of-sight (NLoS) transmission are further considered. The analysis demonstrates that when the activated BS density is larger than a threshold, the coverage is su_er a decrease, which results in a slow growth or a decrease in ASE. Since LoS and NLoS transmission are considered, the probability of an interference path changing from NLoS to LoS becomes larger. As a result, the deployment of SCNs should be paid more attention as increasing BS density will probably lead to a small improvement of network performance or even a worse result. In addition to dense SCNs, mMIMO, considered as a scaled-up version of multiuser MIMO (MU-MIMO), it is important to note that the larger the number of antennas, the larger the number of degrees of freedom, and thus the more multiplexing opportunities. However, when time division duplex (TDD) systems are considered, due to a _nite channel coherent time, the performance of mMIMO systems may be limited by inaccurate channel state information (CSI). Pilot contamination is considered as a major bottleneck, which occurs when the same set of uplink training sequences is reused across neighbouring cells [3]. Other channel estimation impairments also play a role. In this thesis, we conduct performance analysis for uplink (UL) massive multiple input and multiple output (mMIMO) networks using stochastic geometry. With the consideration of practical system assumptions, such as sophisticated path loss model incorporating both LoS and NLoS transmissions and a _nite user equipment (UE) density, we derive the coverage probability and the area spectral e_ciency (ASE) performance.
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Arkhipov, Alexander. "IFDMA for uplink mobile radio communication systems". München Utz, 2010. http://deposit.d-nb.de/cgi-bin/dokserv?id=3440635&prov=M&dokv̲ar=1&doke̲xt=htm.
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Geijer, Lundin Erik. "Uplink Load in CDMA Cellular Radio Systems". Doctoral thesis, Linköpings universitet, Reglerteknik, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-16299.
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The uplink of code division multiple access (CDMA) cellular radio systems is often interference limited. The interference originates from many users whose transmission powers are not observable for the system. This thesis introduces uplink load and applies means of explicitly considering the users’ radio environment when approximating and controlling the load. A desirable property of all cellular radio systems is uplink feasibility, i.e., existence of finite user transmission powers to support the allocated services. Uplink load can be considered as a measure of how far from infeasibility the system is. The performed characterization of uplink load lead to two concrete definitions related to the amount of received and transmitted power, respectively. An important part of the total load is the intercell load which is caused by users connected to neighboring base stations. If not carefully handled, the intercell load can jeopardize uplink feasibility. Conversely, knowledge of a lower intercell load can be used to increase the resource assignments. A common denominator in all the work in this thesis is that the intercell load is explicitly considered. When approximating uplink load, a centralized approach is adopted to study information gathered in several base stations. This yields good approximations of the average load. However, centralized approximations can not detect momentarily peaks in the load. A number of resource allocation algorithms making control decisions in the local base stations are proposed based on experience from characterizing uplink load. As the algorithms study the intercell load, yet without measuring the interference power, they are robust in the sense that they will never assign resources yielding an infeasible system. A straightforward way of controlling the uplink load is to use measurements of the received interference power. This approach, just as the proposed load approximations, can gain from knowing the background noise power. The same framework used for designing robust resource allocation algorithms, is also used for estimating the background noise power.
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Li, Xinyun. "LTE uplink scheduling in multi-core systems". Thesis, KTH, Kommunikationsnät, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-99190.
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With the goal to achieve higher and higher performance with the next-generation of Long Term Evolution (LTE) equipment, multi-core processors are implemented more and more inside LTE eNodeB. The development and increasing use of multi-core processors system raises a challenge to the current scheduling algorithm. The intuitive way of scheduling is a serial process, by which users are scheduled one after another within one cell. It becomes very inefficient in a multi core system, since the parallelism provided by the multi core platform is not fully utilised. The goal of this study is to investigate how the uplink scheduler algorithm can be parallelised efficiently over several DSPs in a multi-core environment. In this thesis, a three-phase algorithm is presented. For each phase, two solutions are provided and evaluated against each other in terms of throughput, time efficiency and fairness, the result is compared with serial scheduling process. The simulation result indicates that the parallel scheduling algorithm is able to achieve higher time efficiency than serial scheduling algorithm, while keeping the same throughput performance. The time improvement depends on the number of schedulable UEs in the system, processors number, the solution used in each phase and the throughput trade-off.
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Tiwari, K. (Kushal). "PAPR aware power allocation in OFDMA uplink". Master's thesis, University of Oulu, 2015. http://urn.fi/URN:NBN:fi:oulu-201505281714.
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This thesis investigates the power allocation scheme and essential design constraints to be considered in multicarrier systems particularly in the case of orthogonal frequency division multiple access (OFDMA) system in multiuser (MU) scenario. The compatibility between multicarrier system and multiple input multiple output (MIMO) system is exploited in designing the power allocation algorithm for a cellular network with multiusers. The multicarrier MIMO system facilitates dynamic resource allocation due to the decomposition of physical resources into multiple domains. The energy efficiency and interference management are the crucial aspects especially in uplink (UL) transmission. Limiting the power consumption of mobile terminals (MT) in uplink (UL) is inevitable due to the limited amount of available energy. Furthermore, the traditional multicarrier system introduces a dynamic peak power variation with respect to average power causing erroneous circuit behavior. This phenomenon is usually quantified as peak to average power ratio (PAPR). High PAPR drives the high power amplifier (HPA) into non-linear region to result in significant degradation in the system performance in terms of power efficiency. In this thesis an iterative power allocation algorithm is proposed to minimize the sum power and PAPR.
This thesis presents the power allocation strategy such that the PAPR is controlled during the power allocation (minimization) stage in frequency domain. The optimal power allocation is achieved by joint optimization of transmit power and receive beamformers (TX-RX) using convex optimization technique. The original problem is not jointly convex with respect to TX-RX. Therefore an iterative algorithm is proposed to optimize TX and RX alternatingly such that by calculating TX for given fixed set of RX and vice versa until convergence. The statistical approach is adopted to reduce the PAPR by actually minimizing the signal power variance (SPV) due to the fact that the large number of independent and identically distributed complex OFDMA symbols tends to follow Gaussian probability density function characterized by certain mean and variance. The non-convex constraints in the formulation are transformed into convex form using the successive convex approximation (SCA) with required change of variable (COV). The algorithm guarantees to maintain the user-specific quality of service (QoS) defined by the rate constraint.
Hence, equipped with the potentials of future generation technologies and using convex optimization as a tool, this thesis offers a sum power and PAPR minimization scheme for MU SIMO-OFDMA UL transmission.
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Conde, Eduardo Manuel Diogo. "Detection techniques for the uplink of LTE". Master's thesis, Universidade de Aveiro, 2012. http://hdl.handle.net/10773/10181.
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Mestrado em Engenharia Electrónica e TelecomunicaçõesNos dias de hoje a internet móvel está em rápida expansão devido aos smart- phones e outros dispositivos móveis. Cada vez mais o acesso á Internet á feito por ligações sem fios, permitindo que os utilizadores se liguem á Internet em qualquer lugar. Devido ao aumento do número de utilizadores e de serviços e por consequente o aumento de largura de banda, é necessário implementar novas arquitecturas que consigam acomodar essas taxas de transmissão e que também sejam rentáveis para as operadoras de telecomunicações. O LTE é assim uma das tecnologias promissoras para o aumento de tráfego verificado nestes últimos anos nas redes celulares. Por detrás da tecnologia LTE estão sistemas de acesso múltiplo que usam múltiplas portadoras ortogonais baseadas no OFDM, sendo o OFDMA usado para o downlink e o SC-FDMA para o uplink. Outro conceito usado pelo LTE são os sistemas MIMO que aumentam a eficiência espectral e a taxa de transmissão de dados. Esta dissertação tem por base a camada física do LTE (camada 1 do modelo OSI), nomeadamente a comunicação de dados no sentido ascendente baseada na técnica de acesso múltiplo SC-FDMA. Foi implementada numa plataforma de simulação um receptor com um equalizador no domínio da frequência iterativo, onde foram usadas várias configurações MIMO com o meio partilhado por vários utilizadores. Os resultados obtidos permitem comparar a eficácia deste tipo de equalizadores versus os equalizadores lineares como o ZF e MMSE tanto na eliminação das interferências como na atenuação do efeito near-far. Os resultados obtidos mostraram-se bastante satisfatórios conseguindo-se remover grande parte dos efeitos da interferências entre símbolos e/ou de múltiplo acesso obtendo-se um desempenho muito próximo do obtido considerando um filtro adaptado. Para além disso a diferença de potência entre os utilizadores não afectou o desempenho do equalizador.
Nowadays, the mobile web is in an accelerated expansion brought by the introduction of smartphones and other mobile devices. Access to the Internet by wireless networks is more and more used because it allows the users to connect to the Internet anywhere. Thus, with the increase of the number of users and services whose by consequence increase the used bandwidth, there is the need to implement new architectures to cope with the demanded transmission rates while being rentable for mobile network carriers. LTE is one of the most relevant technologies to the observed increase of traffic in the last years in cellular networks. Behind this technology, multiple access systems which use multiple orthogonal subcarriers based on OFDM are used, being OFDMA used for the downlink and SC-FDMA for the uplink. Another concept used by LTE is the MIMO systems which increase the spectral efficiency and the data rate. This thesis work is based on the physical layer of LTE (layer 1 of OSI model), namely the uplink communication with its multiple access technique SC-FDMA. It was implemented in a simulation platform an iterative frequency-domain receiver where multiple MIMO configurations were used in a multiple access environment. The obtained results allows comparison of the efficacy in removing interference and also the attenuation of the nearfar effect between linear frequency domain receivers such as ZF and MMSE and iterative frequency domain receivers. The results were successful in the cancellation of inter-symbol interference and multiple access interference. The obtained performance is very close to the one obtained by the matched filter. Moreover, the difference of power between the users did not affect the performance of the equalizer.
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Cunha, Rodrigo Lopes da. "Uplink video traffic determination and network optimization". Master's thesis, Universidade de Aveiro, 2017. http://hdl.handle.net/10773/23487.
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Mestrado em Engenharia de Computadores e TelemáticaCom o aumento do número de plataformas de transmissão de vídeo, as operadoras têm sofrido uma maior sobrecarga nas suas redes. De forma a fornecer uma melhor gestão dessas mesmas redes, garantindo qualidade de serviço a todos os clientes, torna-se necessário dar prioridade ao tráfego correspondente a vídeo aplicando novos conveitos na área das telecomunicações, como é o caso de Software-Defined Networking. Esta dissertação procura, numa primeira fase, apresentar uma revisão de vários temas relacionados com a determinação de tráfego de vídeo, Software-Defined Networking e qualidade de serviço. Posteriormente, é apresentada uma solução de uma aplicação de monitorização, que tem como objetivo, a deteção de tráfego de vídeo, de forma a ajudar na priorização de tráfego e na otimização da rede. A solução é validada através de uma implementação, baseada na performance e na baixa latência do sistema, que procura responder o mais rápido possível com informação sobre um determinado fluxo de pacotes na rede. São ainda apresentados resultados relativos a esta implementação.
With the increase of live streaming platforms, service providers have been experiencing a overhead on their networks. In order to provide a better management of these networks, ensuring quality of service to all customers, it is necessary to prioritize video traffic using new concepts being introduced into the telecommunications field, such as Software-Defined Networking. Firstly, this dissertation aims to present a review of several topics related with video traffic determination, Software-Defned Networking and quality of service. Secondly, a monitoring application solution is presented, which aims to detect video traffic in order to help the prioritization of traffic and network optimization. The solution is validated through an implementation, based on the system’s performance and low latency, which tries to reply as quickly as possible with information about a certain flow of network packets. Results related with this implementation are also presented
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Jersenius, Kristina. "Uplink Channel Dependent Scheduling for Future Cellular Systems". Thesis, Linköping University, Department of Electrical Engineering, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-8213.
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One goal in the development of future cellular systems is to increase performance. Channel dependent scheduling can possibly contribute to a performance enhancement. It requires channel qualityinformation and uplink channel knowledge is often incomplete. This master thesis work compares channel dependent scheduling and channel independent scheduling for a Single Carrier Frequency Division Multiple Access-based uplink in time domain and time and frequencydomain assuming continuous channel quality information updates. It also evaluates different methods for providing channel quality information by investigating how the limited channel knowledge they supply affects the performance of channel dependent scheduling.
Single-cell simulations with perfect channel knowledge indicate small gains for channel dependent scheduling. Large gains are seen when performing frequency and time domain scheduling instead of only time domain scheduling. Limited channel knowledge causes performance loss for channel dependent scheduling. The performance is only slightly decreased if a method with sufficiently frequent providing of channel quality information updates is applied.
More realistic multi-cell simulations show large gains for channel dependent scheduling. It is possible that these results are influenced by link adaptation and scheduling problems due to non predictable interference when performing dynamic scheduling. In the comparison between channel dependent and channel independent scheduling the channel dependent scheduling can benefit from the fact that the selected channel dependent scheduling algorithms result in a more static scheduling than the selected channel independent scheduling algorithms do.
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Shateri, Majid. "Uplink transmit beam-forming for mobile cellular networks". Thesis, University of Surrey, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.538043.
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Karpinsky, Christopher J. (Christopher John) 1972. "Uplink multiple access techniques for satellite communication systems". Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/49644.
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Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1998.Includes bibliographical references (leaves 90-92).
by Christopher J. Karpinsky.
M.S.
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Kedia, Namrata Rajiv. "GUCCI: Ground station Uplink Command and Control Interpreter". Thesis, Virginia Tech, 2016. http://hdl.handle.net/10919/71885.
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For a successful CubeSat mission, it is imperative to schedule events in a fashion that will generate maximum useful science data. Intuitive uplink commanding software is required for the Lower Atmosphere/Ionosphere Coupling Experiment (LAICE) CubeSat to ensure best results. The ground station up-link software is created with this aim in mind. This will make the operation center for the LAICE project efficient. This will also help in evaluating the effect of a particular schedule on LAICE instrument interface board (LIIB) before sending the commands to it. The interactive User Interface (UI) that makes the entire process intuitive guides the user to create an uplink schedule without any human error. The control software creates the command sequence taking in to account all the limitations and specification of the systems and instruments on LAICE. These data are backed up in an efficient format in Virginia Tech’s database for future processing. This web-based application ensures a smooth scheduling process without any errors. Assistive flight-ready software is provided on the flight computer on the LAICE CubeSat to upload the correct uplink sequence to the LIIB.Master of Science
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TAVAKOLI, SANIJ MOHAMAD. "Uplink CoMP Capability Improvements In Heterogeneous Cellular Networks". Doctoral thesis, Politecnico di Torino, 2016. http://hdl.handle.net/11583/2644436.
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LTE-Advanced meets the challenge raised by powerful, mobile devices and bandwidth-hungry applications by investing in solutions such as carrier aggregation, higher order MIMO, relay nodes and Coordinated Multipoint (CoMP) transmission/reception. The latter, in particular, is envisioned to be one of the most important techniques in LTE-Advanced to improve the throughput and functionality of cell borders. CoMP allows users to have multiple data transmission and reception from/toward multiple cooperating eNodeBs (eNBs), increasing the utilization factor of the network. Resource allocation in the uplink is especially beneficial because more sophisticated algorithms can leverage the availability of additional connection points where the signal from the User Equipment (UE) is processed, ultimately providing UEs with increased throughput. Additionally, a significant part of the interference caused by neighboring cells can be seen as a useful received signal thanks to CoMP, provided those cells are part of the Coordinated Reception Point (CRP) set. This is especially important in critical regions, in terms of interference, like cell edges. Finally, in the case of joint multi-cell scheduling, CoMP introduces a reduction in the backhaul load by requiring only scheduling data to be transferred between coordinated eNBs.
Arguably, CoMP is most appealing in the uplink direction since it does not require UE modifications: indeed, users need not be aware that there is any kind of cooperation among receiving eNBs. UEs are merely scheduled for transmission on a set of frequencies that happens to be split among different eNBs, although they still retain standard signaling channels through only one of these eNBs, usually referred to as the serving cell.
In this work we focus on uplink CoMP from a system point of view. Specifically, we are interested in comparing through simulation the performance of uplink CoMP in various scenarios with different user participation to CoMP transmissions and CoMP margins. Some works have already investigated uplink CoMP both in simulation and through field trials. Our contribution confirms the findings of previous works as far as the throughput gain for edge users is concerned, but introduces three novel observations that can spur future investigations on CoMP systems, in both downlink and uplink regime, and lead to the design of new resource allocation algorithms:
• We look at Heterogeneous scenario where there is no restriction in the type of cells that can be in the CRP set, but simultaneously we introduce clustering option included limited number of Macro and small cells to be acted independently from other clusters in CoMP process.
• We introduce a parameter called CoMP Pool Percentage (CPP), which quantifies the fraction of PRBs that are reserved for UEs using a specific eNB as CRP (out of the resources nominally available to that eNB). Our algorithm show that the setting of CPP must be carefully gauged depending on the number of CoMP users and the scenario.
• We proposed an innovative dynamic algorithm to make decision of the CPP value in order to improve the gain for CoMP users while considering the whole network gain.
Combination of the three above mentioned routine and algorithms, according to simulations, confirms an average gain of at least 20% percent for the CoMP users, (average over various population) locating in cell boarder, while the whole network benefits by average of 5% gain for all the users (see results section). The algorithm also guarantees more gain for more values of CoMP margin. In other words, the more the population of CoMP users locating in cell borders the more would be the achievable gain.
Objectives of this PhD thesis are concluded as follows:
• Design a Network-level simulator whose features are close to a real LTE network, including advanced capabilities and innovations
• Observe the response of the network to parameters changes
• Increase the throughput gain (using CoMP vs. non using it) and the quality of service
• Design and evaluate the Novel Scheduling Algorithm
• Compare the obtained results with real cases
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Hearn, Christian W. "Electrical Design and Testing of an Uplink Antenna for Nanosatellite Applications". Thesis, Virginia Tech, 2001. http://hdl.handle.net/10919/35286.
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Virginia Tech, Utah State University, and the University of Washington were teamed to form the Ionospheric Observation Nanosat Formation to investigate formation-flying requirements for multiple spacecraft missions. A communication subsystem for the mission will comprise an uplink, downlink and a satellite-to-satellite crosslink.
A linearly polarized resonant loop antenna mounted above the bottom surface of the spacecraft was selected for a possible satellite uplink receive antenna. The resonant loop was chosen to satisfy the physical requirements of the spacecraft whild still achieving efficient operation for a UHF signal.
A full-scale prototype was fabricated to measure frequency dependent characteristics of the antenna. A gamma match and a quarter-wave sleeve balun transformer were integrated to the system to minimize the power reflected at the antenna input and to isolate the antenna from the feed line.
The uplink antenna demonstrated sufficient performance; however, the final bandwidth of less than one percent will require additional tuning as other subsystems are integrated into the final flight-ready prototype.Master of Science
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Ha, J. Y. "WDM/SCM PON incorporating a novel CWDM uplink combiner". Thesis, University of Cambridge, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.599814.
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There is currently much interest in the use of passive optical networks (PONs) for applications such as fibre to the home, fibre to the curb and fibre to the building. Some of these schemes use time division multiple access (TDMA), this enabling many users to share an optical channel with a bandwidth of typically up to 10-Gb/s. However, high speed implementations involve high bandwidth components at the customers’ premises, and require ranging and scheduling on the uplink to avoid interference induced by multiple users simultaneously transmitting in the same optical channel. Leveraging recent advances in high speed RF technologies, subcarrier multiplexing (SCM) has been proposed as an alternative to time division multiplexing and code division multiplexing access technologies for PON applications. The proponents of SCM have cited advantages of flexible protocol transmission (where different channels can therefore be used for different services), easy upgradeability of present access networks and good fibre transmission performance. However, significant disadvantages have been acknowledged including in particular the generation of optical beat interference (OBI) between uplink sources. In this PhD dissertation, therefore, a bandwidth symmetric wavelength division multiplexed (WDM)/SCM-PON architecture incorporating a novel uplink combiner as a solution to remove OBI and provide large bandwidths (> 1-GB/s) to the home is proposed. Here, the virtually-passive uplink combiner allows the simple and linear combination of SCM channels from multiple local users and inexpensive user components. In the proposed scheme, binary phase shift keying (BPSK), quadrature phase shift keying (QPSK) and 16 quadrature amplitude (16QAM) modulations are used as base-band modulation schemes respectively. In order to enable a spectrally efficient (> 1-bit/s/Hz) multi optical user network, the QPSK and 16QAM SCM PON are studied in detail. A proof-of-principle experimental demonstration of a dual channel multi-user optical network using SCM-QPSK and 16 QAM modulation for high spectral efficiency is reported. In order to show the potential of feasibility of a 1-Gb/s BPSK, QPSK, and 16QAM SCM PON, computer simulation using a time domain model is performed, showing that each optical channel is respectively capable of supporting 10 x 1-Gb/s QPSK and 20 x 1-Gb/s 16QAM dedicated links, and so serving 400 users and 800 users simultaneously when using 40 dense WDM (DWDM) channels.
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Sayin, Alp. "VHF/UHF Uplink Solutions for Remote Wireless Sensor Networks". Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-123514.
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The purpose of this thesis was to compare alternative wireless links for transfer of data from sink motes of remote wireless sensor networks to a central repository. A few different protocol stacks to be implemented in the WSN (Wireless Sensor Network) uplink gateway and along with them a few implementation environments based on open source software and low-power hardware were discussed. To facilitate measurements and experimental validation, some of the alternatives have been implemented. Experiments have been made using two of the amateur radio bands, the 144 MHz band (VHF) and the 433 MHz band (UHF). The parameters studied include throughput, range, power-requirements, portability and compatibility with standards. Using different protocol stacks, different bands and sometimes different hardware 5 solutions were designed, implemented, tested and experimented with. Namely these solutions are called Radiotftp, Radiotftp_process, Radiotunnel, Soundmodem and APRX in this thesis. After the implementation phase, there was an open-field experimentation to measure the aforementioned parameters. The tests were conducted in Riddarholmen, Stockholm of Sweden. These open-field experiments helped us obtain real-life measurements about power, throughput, stability etc. Experiments were conducted in a range of from a minimum of 2 meters to a maximum of 2.1 kilometers with some of the solutions. In the end, some of these solutions proved themselves to be viable for the purpose of data communications for remote wireless sensor networks. Radiotftp gave the best throughput in both bands where it proved itself to be difficult to develop further applications. Radiotftp_process removed the necessity for a Linux running gateway machine but it was unable to work with faster baud rates. Radiotunnel opened up the path for a range of network applications to use radio links, but it also proved that it was unstable. On the other hand Soundmodem and APRX which were based on standard and open-source software proved that they were stable but rather slow. It was proven that every approach to problem has its advantages and disadvantages from different aspects such as throughput, range, power-requirements, portability and compatibility.
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Aziz, Babar. "Frequency synchronization for carrier allocation in uplink OFDMA systems". Phd thesis, Université de Cergy Pontoise, 2011. http://tel.archives-ouvertes.fr/tel-00767906.
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La mise en oeuvre de systèmes basés OFDMA nécessite une synchronisation de la fréquence très fine en raison de l'extrème sensibilité de l'OFDMA aux décalages en fréquence porteuse (CFO). La synchronisation en fréquence devient plus difficile dans les systèmes OFDMA en liaison montante. Nos objectifs comprennent l'étude et l'analyse des problèmes résultant de décalages de fréquence et la proposition de solutions pour lutter contre ces problèmes. Nous examinons d'abord les interférences résultant de décalages de fréquence porteuse présents dans l'oscillateur du terminal utilisateur. Nous démontrons que l'on doit prendre en compte le préfixe cyclique tout en analysant les interférences résultant du CFO. Ensuite, nous montrons qu'il existe une contradiction entre la diversité de fréquence de canal et la robustesse contre le CFO. Nous proposons un compromis sous la forme d'une taille de bloc de seuil, afin de permettre un bon compromis entre la diversité des canaux et de robustesse pour les CFO pour le cas où aucune connaissances du canal n'est disponible. Quand le canal est connu, nous proposons une allocation optimale par bloc grâce à laquelle la robustesse aux CFO et à la diversité de fréquence de canal peut être réalisée en utilisant une petite taille de bloc petit pour des CFO de petite valeur. Nous proposons également une valeur CFO critique, en dessous de laquelle l'allocation optimal par bloc est très performant. Ensuite, nous proposons des solutions pour deux problèmes importants rencontrés dans un système OFDMA en liaison montante. Premièrement, nous proposons une méthode efficace pour l'estimation conjointe des réponses impulsionnelles des canaux et fréquences porteuses basée sur l'approximation polynomiale. Notre méthode d'estimation conjointe est plus simple que les méthodes existantes, sans aucune dégradation de performance. Ensuite, nous proposons une méthode de compensation de CFO basée sur l'annulation des interférences successives (SIC). La méthode d'annulation proposée réduit la complexité de mise en oeuvre quand le nombre de porteuses est important.
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Jiang, Ming. "Hybrid multi-user OFDM uplink systems using multiple antennas". Thesis, University of Southampton, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.427404.
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Brandão, Maria João Pinho. "Behavioral modeling of the NB-IoT Uplink physical laye". Master's thesis, Universidade de Aveiro, 2017. http://hdl.handle.net/10773/23759.
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Mestrado em Engenharia Eletrónica e TelecomunicaçõesA Internet das Coisas (IoT) consiste numa rede sem fios de sensores/atuadores ligados entre si e que têm a capacidade de recolher dados. Devido ao crescimento rápido do mercado IoT, as redes de longa distância e baixa potência (LPWAN) tornaram-se populares. O NarrowBand-IoT (NB-IoT), desenvolvido pela 3rd Generation Partnership Project (3GPP), é um desses protocolos. O principal objectivo desta dissertação é a implementação de uma simulação comportamental em MATLAB do NB-IoT no uplink, que será disponibilizada abertamente. Esta será focada, primariamente, na camada física e nas suas respetivas funcionalidades, nomeadamente turbo coding, modulação SC-FDMA, modelos de simulação de canal, desmodulação SC-FDMA, estimação de canal, equalizador e turbo decoding. A estimação de canal é feita usando símbolos piloto previamente conhecidos. Os modelos de canal utilizados são baseados nas especificações oficiais da 3GPP. A taxa de bits errados (BER) é calculada e usada de forma a avaliar a performance do turbo encoder e do equalizador zero forcing (ZF). Serve também como comparação quando a implementação usa esquemas de modulação diferentes (Binary Phase-Shift Keying (BPSK) e Quadrature Phase-Shift Keying (QPSK)). Além disso, os sinais gerados em MATLAB são transmitidos usando como front-end de radio-frequência (RF) uma Universal Software Radio Peripheral (USRP). Posteriormente, são recebidos, desmodulados e descodificados. Finalmente, é obtida a constelação do sinal, a BER é calculada e os resultados são analisados.
The Internet of Things (IoT) refers to a wireless network of interconnected sensors/actuators with data-collecting technologies. Low Power Wide Area Networks (LPWAN) have become popular due to the rapid growth of the IoT market. Narrowband-IoT (NB-IoT), developed by 3rd Generation Partnership Project (3GPP), is one of these protocols. The main objective of this thesis is the implementation of an open-source uplink behavioral simulator based on MATLAB. Its focus is primarily on Layer 1 (physical layer) relevant functionalities, namely turbo coding, Single-Carrier Frequency-Division Multiple Access (SC-FDMA) modulation, channel modeling, SC-FDMA demodulation, channel estimation, equalization and turbo decoding. Channel estimation is performed using known pilot symbols. The used channel models are based on the 3GPP o cial release specs. The Bit Error Rate (BER) is calculated in order to evaluate the turbo encoder and the Zero Forcing (ZF) equalizer performance, and to compare Binary Phase-Shift Keying (BPSK) and Quadrature Phase-Shift Keying (QPSK) implementations. Furthermore, the MATLAB generated signal is transmitted using a radio-frequency (RF) front-end consisting of an Universal Software Radio Peripheral (USRP). Afterwards, the signal is received, demodulated and decoded. A constellation is obtained, the BER is calculated and the results are analyzed.
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chu-hen, chiou y 邱祖恆. "A DSP-based uplink WCDMA". Thesis, 2004. http://ndltd.ncl.edu.tw/handle/39177314510345128529.
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碩士國立臺灣大學
電信工程學研究所
92
With the advance of integrated circuits and communication technology, mobile communication has been widely used in daily life. The service and contents also become more and more diversified. Therefore, third generation mobile communication service has emerged to become the future of telecommunication. To meet the massive requirements of bandwidth and avoid signal interference and noise, researchers around the world work hard with the focus on channeling characteristics. The purpose of using equalizer, rake receiver, and smart antenna technology is to reduce the influence of channeling effect and hence maintain certain quality of service. However, such technologies necessitate complex circuits. It is a mammoth challenge to design with new signal processing technology without increasing volume and power consumption of circuits at the same time. In this research, the transceiver of a third generation mobile communication system is analyzed and studied. Several concerns are brought up in the fabrication process of wideband code division multiple access transceiver. Programmable logic array chipsets are also used to test and verify signal transmission in the real world. Through extensive experiments it is expected to understand the function of whole system and the application model of channel measurement data
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Paramatmuni, P. K. "LTE Baseband Algorithms for Uplink". Thesis, 2013. http://raiith.iith.ac.in/721/1/EE11M1009.pdf.
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LTE is a next generation mobile system from the 3GPP with a focus on wireless broadband.The aim of LTE is to achieve high data rates in both uplink & downlink, and to achieve high spectral efficiencies.The main focus of the work is to develop baseband algorithms in the uplink in order to achieve uplinksynchronization between the user and the base station and also for the detection of the control data that is transmitted.
For the base station to obtain the knowledge of the presence of the user and also about its position, the user has to transmit synchronization signals to the base station, which are transmitted on the Physical Random Access CHannel (PRACH) in LTE. These signals are used to obtain the uplink timing correction and hence synchronize with the base station.
It is very important for the base station to detect the control data that has been transmitted by the user on Physical Uplink Control CHannel (PUCCH). The control data may consist of the response of the UE to the data packets that were transmitted by the base station, request for resource allocation etc.So efficient algorithms are necessary for the accurate detection of the control data at the base station.
The current work presents algorithms that are essential for obtaining uplink synchronization and also for efficient detection of the control channel data.
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Chang, Li-Yen y 張立言. "Uplink-Downlink Beamforming Design for Full-duplex Cloud Radio Access Network with Wyner-Ziv uplink Compression". Thesis, 2019. http://ndltd.ncl.edu.tw/handle/568rk9.
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碩士國立臺灣科技大學
電子工程系
107
In this thesis, we consider a cloud radio acess network (CRAN) with nite fronthaul capacity architecture, which includes a centralized baseband unit (BBU) pool and a set of full-duplex (FD) remote radio heads (RRHs) serving a set of half-duplex (HD) downlink and uplink mobile users. Our goal is to minimize total transmit power of RRHs and uplink mobile users under each SINR and fronthaul capacity constraints. First, we consider a per-base-station successive interference cancellation (SIC) scheme that performs Wyner-Ziv compress-and-forward at RRHs, we use half-duplex system model at RRHs and derive achievable rate for uplink users under nite fronthaul link. Further we use full-duplex system model at RRHs, compared to half-duplex model, now we have to manage the interference such as self-interference, inter- RRH interference and uplink to downlink interference. Secondorder cone program (SOCP) based algorithm is proposed to solve power minimization problem and Uplink-Downlink Duality strategies is proposed to reduce calculation complexity. Simulation results are presented to evaluate the proposed algorithms.
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Huang, Yi-Shan y 黃義珊. "Channel Estimation for Uplink WCDMA System". Thesis, 2000. http://ndltd.ncl.edu.tw/handle/41067972043122808842.
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碩士國立交通大學
電子工程系
88
In this thesis, the channel estimation methods for next generation wideband code-division multiple-access (WCDMA) system were studied. Coherent WCDMA reverse link periodically transmitting pilot symbols in front of every control channel slot to estimate the fading channel is considered. For the WCDMA reverse link, fast transmit power control (TPC) and power saving of mobile station are the important issues. We proposed moving average method and sliding window methods to overcome the decision delay of the control symbols. We also proposed a low-complexity channel estimation method based on both control and data channels to reduce the required power of a control channel. After investigation and simulation in this thesis, we conclude that the sliding window type-VI channel estimation based on both control and data channels is better than other methods in the overall performance of BER, delay time and power reduction.
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Ho, Hsin-Che y 何欣哲. "Pilot Design in Uplink OFDMA Systems". Thesis, 2008. http://ndltd.ncl.edu.tw/handle/94795720010942199866.
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碩士國立中山大學
通訊工程研究所
96
In this thesis, One of the difficulties in the orthogonal frequency division multiple access (OFDMA) systems is the multi-user interference (MUI) induced by the carrier frequency offset (CFO). In sub-band OFDMA systems, each user occupies a consecutive and non-overlapping frequency sub-band. The pilots are usually placed at the edges of a sub-band for frequency synchronization and channel estimation. However, the both frequency synchronization and channel estimation performance are influenced seriously by the multi-user interference (MUI) induced by CFO of other users. The MUI can be reduced by inserting the guard sub-carrier between adjacent users. In this paper, a novel pilot architecture is investigated, which has the same bandwidth efficiency as the conventional guard sub-carrier insertion scheme. In addition, the proposed pilot architecture provides better carrier frequency synchronization and channel estimation performance than conventional pilot assignment. Moreover, this new pilot architecture also has MUI reduction utility.
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TU, BO-HAO y 凃柏豪. "Uplink Access Control in Narrowband IoT". Thesis, 2019. http://ndltd.ncl.edu.tw/handle/7e7x32.
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碩士國立中正大學
資訊工程研究所
107
In order to provide low-power wide area network (LPWAN) services, 3GPP adopted the Narrow-Band IoT (NB-IoT) core protocol standard in June 2016, expecting NB-IoT to become the transmission communication standard used in future service networking applications, with the goal of providing a large number of IoT devices. These IoT devices will connect to NB-IoT base stations, providing a wider range of coverage with low power consumption and a better sleep mechanism to extend better battery life. In the development of the Internet of Things, the development of the NB-IoT network has encountered some challenges. First, the design of NB-IoT is used for machine type transmission. Generally, delay time is not the primary consideration for this type of transmission. However, different types of IoT devices or applications may have different tolerances for delay time. For example, for life-threatening or life-saving devices, such as emergency medical care, they would require very low latency transmission for emergency messages and thus need special treatments. Secondly, when the user equipment starts to enter the NB-IoT network, it must synchronize with the regional base station through the random access channel (RACH) procedure. The future 5G network is expected to accommodate a density of one million IoT devices per square kilometer, which will accompany with the large number of random access requirements and causes a big challenge to the random access procedure. Therefore, how to improve the random access process to handle a large number of IoT devices without affecting the transmission of emergent messages is the focus of this thesis. In this thesis, we proposed Dynamic RACH Resource Allocation (DRRA) scheme which integrates with resource allocation scheme and ACB scheme to improve the random access process. Our simulation results show that the proposed DRRA scheme is able to achieve higher access success rate and low delay of emergent message transmission type as compared to the original standard RACH procedure.
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Vijayan, Divya. "Adaptive channel estimation for LTE uplink". Thesis, 2013. http://ethesis.nitrkl.ac.in/4644/1/211EC4112.pdf.
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Third generation partnership project (3GPP) long term evolution (LTE) uses single carrier frequency division multiple access (SC-FDMA) in uplink transmission and orthogonal frequency division multiple access (OFDMA) scheme for the downlink. A variable step size based least mean squares (LMS) algorithm is formulated for a single carrier frequency division multiple access (SC-FDMA) system, in its channel estimation (CE). The weighting coefficients on the channel condition can be updated using this unbiased CE method. Channel and noise statistics information are not essential. Rather, it uses a phase weighting scheme to eliminate the signal fluctuations due to noise and decision errors. The convergence towards the true channel coefficient is guaranteed. The proposed algorithm is compared with the existing algorithms for BER and MSE performance in different channel environments.
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Wang, Xin-Jie y 王信傑. "Differential Modulation in Uplink Massive MIMO Systems". Thesis, 2017. http://ndltd.ncl.edu.tw/handle/89375510090922085336.
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碩士國立中央大學
通訊工程學系
105
Massive MIMO systems are popular studies in recent years. Differential encoding scheme is not required to transmit pilot sequence for channel estimation, so it does not cause pilot contamination. A differentially encoded QAM (quadrature amplitude modulation) scheme for uplink massive MIMO was proposed recently which outperforms conventional differential APSK (amplitude-phase shift keying) scheme for 1000 receiver antennas. In this letter, we raise and try to resolve some questions about this differential QAM scheme. We construct new tables for differentially encoded 16-QAM. We compare differential 16-QAM with differential 16-APSK for the same detector, and compare the detector with a conventional detector for the same transmitter. Simulation results show that differential 16-APSK has the best error performance for any number of receiver antennas. Besides, we propose a new scheme for uplink coherent massive MIMO. This scheme uses transmitted data signal as pilot sequences, and we also design the pilot sequences to make it orthogonal to each other, which can shorten the time of transmission of the pilot sequence.
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SALAH, Mohamed. "Comparative Performance Study of LTE Uplink Schedulers". Thesis, 2011. http://hdl.handle.net/1974/6509.
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Long Term Evolution (LTE) constitutes a significant milestone in the evolution of 3G systems towards fourth generation (4G) technologies. The performance targets promised by LTE makes it an ideal solution to accommodate the ever increasing demand for wireless broadband. LTE's promised performance targets were made possible due to improvements such as a simplified system access architecture and a fully IP-based platform. LTE has also great enhancements in its enabling radio technologies by introducing Orthogonal Frequency Division Multiplexing (OFDM) and advanced antenna technologies. In addition, LTE capabilities are further improved with enhanced Quality of Service (QoS) support for multiple data services, such as voice and other multimedia applications.
LTE packet scheduling plays an essential role as part of LTE's Radio Resource Management (RRM) to enhance the system's data rate and to support the diverse QoS requirements of mobile services. LTE packet scheduler should intelligently allocate radio resources to mobile User Equipments (UEs) such that the LTE network adheres to its performance requirements. In our work, we perform a performance evaluation of multiple LTE scheduling algorithms proposed for LTE uplink transmission. The evaluation takes place in single and mixed traffic scenarios to exploit the strengths and weaknesses of proposed algorithms. Simulation results illustrated the importance of a scheduler's awareness of uplink channel conditions and QoS requirements in the presence of single and multiple traffic scenarios. Accordingly, we provide recommendations for future scheduling algorithm proposals, and ways to enhance the existing schedulers.Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2011-05-07 12:43:54.983
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Peng, Chun-Chen y 彭崇禎. "Uplink Scheduling Schemes in EPON Access Network". Thesis, 2004. http://ndltd.ncl.edu.tw/handle/q82kx3.
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碩士國立交通大學
電信工程系所
92
Rapid deployment of broadband services in the residential and small business area has played an important role in the evolution of access networks. Currently, Ethernet passive optical networks (EPON) are being considered as a promising solution for the next generation access network, due to the convergence of low-cost Ethernet equipment and low-cost of fiber infrastructure. In addition, the growing demand of broadband services such as IP telephony, video on demand has urged the network operator to accelerate the deployment of full-service access networks. In this thesis, we proposed a delay-considered scheduling scheme for real-time services, i.e. voice and video service, and two fairness-considered scheduling schemes, i.e. Hybrid LQF-QLP scheme and Hybrid EQL-QLP scheme, to support non-real-time data service. The goal of the scheduling algorithm is to meet the delay bound of voice service, and to simultaneously maintain the fairness of both packet delay and packet blocking probability for non-real-time data service. Simulation results show that the proposed scheduling method can meet our goal. In addition, we proposed a prediction-based scheduling method, in which we adopt a Moving Average technique. We find that by implementing a predictor, the maximum cycle time can be extended and the system throughput can be improved. Simulation results show that the proposed scenario can improve performance well.
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Chang, Shu-Hao y 張書豪. "Physical Layer of LTE-Advanced Uplink Transmission". Thesis, 2014. http://ndltd.ncl.edu.tw/handle/745575.
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碩士國立臺北科技大學
電腦與通訊研究所
102
LTE-A (Long-Term Evolution Advanced) is specified criterion for fourth generation mobile communication at present, all of fourth generation''s version are definition by Third Generation Partnership Project (3GPP). This thesis is discuss about the data bits from Transport Channels to Physical Channels for transmission process, First, Time Division Duplexing (TDD) of the LTE-A system began to introduce and explain the Frame Structure. Since the LTE-A uplink slot structure and physical resources, we introduce the uplink transmit of data bits from Transport Channels to Physical Channels for transmission process basic system architecture, and in the process of the basic architecture of each block in detail above classification. Finally, the LTE-A uplink of the Physical uplink share channel and basic system architecture is described.
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Tseng, Ping-Yi y 曾平一. "Throughput Analysis of TDD/CDMA Uplink Systems". Thesis, 2006. http://ndltd.ncl.edu.tw/handle/96962607201581838924.
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碩士大葉大學
電信工程學系碩士班
94
The interference time ratio and multiple access interference from both base stations (BSs) and mobile stations (MSs) are analyzed for TDD/CDMA uplink systems, and the uplink throughput is evaluated according to a required outage probability. Only the path loss and shadowing effect in the mobile radio channel are considered in our investigating, while the effect of multi-path fading is assumed to be compensated by signal processing and channel coding. In regarding to the interference time ratio, we find that the interference time ratio increases as the cell radius increases for the interfering BSs. For the interfering MSs, the interference time ratio increases as the distance between the MS and the interfered BS decreases. In regarding to the capacity loss due to the cell size, for a 50% down-link cell coverage, when the cell radius increases from 100 m to 5,000 m and 10,000 m, the capacity loss is 45.1% and 87% respectively. For a 85% down-link cell, the loss is 37.5% and 93.7% respectively. While for a 95% down-link cell, the loss is 53.8% and 92.3% respectively. We find that the capacity loss increases as the cell radius and the cell coverage increase. Therefore it is a better choice to deploy TDD/CDMA systems in the micro-cells. Because the BSs tend to transmit more power for a higher downlink cell coverage, the associate interference also increased, and the capacity decreases accordingly. As a result, the downlink power control should be used to reduce the BSs transmitted power.
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Huang, Ding-Yu y 黃鼎御. "Hybrid Uplink Scheduling for Discontinuous Realtime Traffic". Thesis, 2012. http://ndltd.ncl.edu.tw/handle/53495308222300323856.
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碩士國立暨南國際大學
電機工程學系
101
Taking the advantage of silence suppression, the communication systems need not to allocate radio resources for the users in silence state. By doing so, the system capacity can be significantly improved. The main issue for the systems with discontinuous re- altime traffic is how to immediately allocate resources, while the users reactivate and transit from the silence state to active state. Traditionally, there are two typical band- width request (BR) methods: the unicast-polling and the multicast-polling methods. The unicast-polling BR method can guarantee the bandwidth request delay, but at the cost of much more resources allocated for bandwidth requests. The multicast-polling method has lower resource overhead needed for bandwidth requests, whereas cannot ensure the bandwidth request delay because of contention collisions. In this thesis, we propose the hybrid-multicast/unicast-polling method, which combines the multicast polling and unicast polling. In the proposed hybrid BR method, we can adopt longer period for the unicast-polling to lower resource overhead used for polling, and shorter period for the multicast-polling to reduce the bandwidth request delay. To compare the hybrid-polling, unicast-polling, multicast-polling methods, we develop analytical models to evaluate bandwidth request delay, delay variance, bandwidth request failure probability, and resource overhead for BR polling. On the top of analytical mod- els, we formulate the optimization problem to determine the period of polling, and resource units in a multicast-polling contention window, aiming to minimize the re- source overhead for BR polling, under the requirements of bandwidth request delay and bandwidth request failure probability. Numerical results show that the proposed hybrid-polling method achieves comparable resource overhead for bandwidth request as the multicast-polling method, with a guaranteed bandwidth request delay. We have also performed extensive simulations to verify the analytical models. The analytical models can provide important insights for network planning to ensure the bandwidth request delay and lower resource overhead for bandwidth request.
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Kuo, Sheng-Chung y 郭勝中. "Carrier Frequency Offset Estimation for OFDMA Uplink". Thesis, 2010. http://ndltd.ncl.edu.tw/handle/80684360018419579289.
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碩士國立中央大學
通訊工程研究所
98
In OFDMA uplink systems, carrier frequency offset (CFO) would cause inter carrier interference (ICI) and multiple access interference (MAI), and would degrade the system performance. Blind CFO estimation algorithms have been proposed in lot of papers, and [1] proposed the MUSIC algorithm with excellent performance, but the MUSIC algorithm includes two operation that are hard for hardware to implement, to acquire the noise subspace and grid search procedure that depends on search resolution, besides, the wireless communication system transmission unit is frame, but the channel and CFO will change along the symbols, so if we estimate the CFO per symbol isn’t efficiency, so in this paper, we applied a fast data projection method (FDPM) to get the noise subspace and proposed a iterative MUSIC scheme to estimate the CFO over frame rapidly.
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Lu, Chih-Yuan y 盧志遠. "Initial Uplink Synchronization for the IEEE 802.16e". Thesis, 2008. http://ndltd.ncl.edu.tw/handle/24277906341120785334.
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碩士國立中正大學
通訊工程研究所
96
IEEE wireless MAN standard IEEE 802.16 has been considered for the next generation wireless communication system. Orthogonal frequency division multiple access (OFDMA) has recently received significant interest and has been adopted as one of the physical layer modes in the IEEE wireless MAN 802.16 standard. In the mutiuser OFDMA environment, each user is allocated with a group of subcarriers. To maintain the orthogonality among the subcarriers in the uplink of OFDMA system, the signals transmitted by all subscriber stations (SS) must arrive at the base station (BS) synchronously. This work is accomplished by an initial uplink synchronization. At the initial uplink synchronization, subscriber stations obtain the base station parameters from downlink broadcast channel. According to these parameters, each SS generates its initial ranging code and transmits two repeated initial ranging symbols to the BS. The BS then determines the ranging code under multipath fading channel for further use. In this thesis, we study the processing procedure at the BS for determining the ranging code. This procedure includes energy detection, frequency synchronization, timing synchronization, and ranging code detection.
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Yin, Wei-Cheng y 尹唯丞. "Robust Channel Estimation in LTE Uplink Transmission". Thesis, 2014. http://ndltd.ncl.edu.tw/handle/59183133871554119116.
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碩士國立交通大學
電子工程學系 電子研究所
103
Wireless communication will play an important role in the evolution of communication in the future, especially basing on WiMAX (IEEE) and LTE (3GPP) to develop individually. The major difference between the two systems is that LTE using single carrier frequency division multiple access(SC-FDMA)technique in uplink transmission, while WiMAX using orthogonal frequency division multiple access(OFDMA).The advantage of using SC-FDMA is to reduce the peak-to-average power ratio (PAPR) which saves the power consumption of user equipment (UEs). This thesis will introduce the subjects of channel estimation problems, algorithms, analysis of multi-path transmission in SC-FDMA. In channel estimation, we first use the least square estimator, then use two different methods to estimate the channel frequency response. The first method is to estimate the correlation matrix of channel by the frequency response of reference signals estimated by least square estimator. Then smooth the channel response of reference signals by linear minimum-mean square error (LMMSE) matrix derived by correlation matrix. The second method is using Gaussian distribution window (GWD) to make reference signal smoother. After estimating frequency response of reference signals, we use linear interpolation to get frequency response of data subcarriers. In simulation, we test and verify the simulate model which we proposed in additive white Gaussian noise(AWGN) channel. Then we simulate in multi-path channel. We find that LMMSE has similar performance as Gaussian distribution window in low SNR, but Gaussian distribution window has lower complexity than LMMSE.
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Shen, Wei-Liang y 沈威良. "MAC Designs for Uplink Multiuser MIMO Systems". Thesis, 2015. http://ndltd.ncl.edu.tw/handle/28868789709454722719.
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博士國立臺灣大學
電機工程學研究所
103
With the popularity of mobile devices and data-intensive applications, the amount of traffic generated by existing wireless networks has been tremendously increasing. This phenomenon introduces the urgent requirement for high speed wireless transmissions. One predominate approach is Multiuser MIMO (MU-MIMO) systems, which exploit multiple antennas equipped at a phyiscal access point or a virtual access point connected by backhaul networks to enable several users to communicate simultaneously. These strategies introduce several new challenges: 1) The optimal ransmission bitrate of a user will change with the concurrent transmitters on a per packet basis.Therefore, traditional historical-based bitrate selection algorithms cannot work in MU-MIMO systems. 2) In a uplink MU-MIMO system, every single error caused by hidden terminals or collisions will corrupt the whole packets.Therefore, MU-MIMO systems are especially more vulnerable to errors than single-user networks. Simply retransmitting collided packets will take away the performance gains provided by multiple concurrent transmissions. 3) A system can further combine multiple access points as a multi-antenna virtual access point. However, in such a ``network MU-MIMO system'', arbitrarily forming several antennas as an access point could increase the probability of inter-cell interference and further decrease channel utilization. How to form practically-sized virtual access points becomes a critical problem in network MIMO systems. This dissertation tries to solve the above problems. First, this dissertation focuses on a single access point scenario, and proposes a MAC protocol for each user to properly select their bitrates based on the channels of concurrent transmitters such that the performance gain provided by MU-MIMO can be fully utilized. To address the error vulnerability problem of MU-MIMO,this dissertation proposes a packet recovery strategy for MU-MIMO systems to repair collided packets without significant overhead. Finally, this dissertation introduces a new structure for network MIMO systems, which adaptively forms practically-size virtual access points based on dynamic client distributions and traffic demands to reduce inter-cell interference and enhance antenna utilization. The above designs have been implemented on software defined radio platforms and analyzed through simulations. In both testbed experiments and simulations, the proposed systems can achieve a significant performance gain, as compared to the traditional wireless network and existing MU-MIMO systems.
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Liao, Yen-Kai y 廖彥凱. "Uplink Scheduling for LTE Video Surveillance Systems". Thesis, 2014. http://ndltd.ncl.edu.tw/handle/20378530724742582097.
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碩士國立清華大學
資訊工程學系
103
Due to the proliferation of applications for the Internet of Things, an increasing number of machine to machine (M2M) devices are being deployed. In particular, one of the M2M applications, video surveillance, has been widely discussed. Long Term Evolution (LTE), which can provide a high rate of data transmission and wide range of coverage, is a promising standard to serve as an M2M video surveillance system. In this thesis, we studied a performance maximization problem in an LTE video surveillance system. Given a set of objects and a set of cameras, each camera has its own performance grade and its own coverage. The goal is to maximize the performance of the system by allocating limited resources to cameras while all objects should be monitored by the selected cameras. We propose a heuristic method to select the cameras and allocate resources to them to solve the problem. Moreover, to reduce the load of the LTE system, a dynamic adjustment method is also proposed.
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Jiun-ShiangChang y 張俊翔. "The Research of WiMAX Uplink Scheduling Algorithm". Thesis, 2010. http://ndltd.ncl.edu.tw/handle/99945582810912080184.
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碩士國立成功大學
電信管理研究所
98
Because of the rapid development of broadband applications in recent years, the quality of service for transmission speed and quality is increased. Hence, the QoS requirement is added in WiMAX standard. Transmission priority depends on service types that users subscribe. This priority arrangement is to ensure data transmission and to meet the application service quality. To meet the demand for QoS, IEEE 802.16e proposes five different scheduling services. When the data streams start to enter the scheduling queue, they will first be classified according to the service requirements. The purpose of classification is to provide different QoS parameters. In the Uplink scheduling algorithms, when a SS establish a connection with BS, BS will implement CAC to check whether enough bandwidth to use. Once the connection is established, BS scheduler will allocate appropriate bandwidth to users. However, the bandwidth assigned to the user may not be able to meet the scheduling service, so users need to re-allocate bandwidth to the schedule services. The goal of this study is to allocate available bandwidth to the schedule for uploading services to meet the non-real-time scheduling service. The proposed schedule method can prevent the non-real-time service from hungry and can enhance its existing bandwidth efficiency. Based on the exist schedule method, this study attempts to propose a new algorithm to improve transmission efficiency. The NS-2 simulator is employed to verify our method. A comparison of network performance between the proposed method and exist schedule method is also given in this thesis
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Deng, Zhi-Hong y 鄧治泓. "Performance analysis in uplink of 3GPP LTE". Thesis, 2010. http://ndltd.ncl.edu.tw/handle/24578982715099904988.
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碩士雲林科技大學
通訊工程研究所碩士班
98
ABSTRACT The cellular technologies specified by 3GPP are the most widely deployed in the world, with more than 2.6 billion users in 2009. 3GPP LTE is the name given to a project within the 3GPP to improve the mobile phone standard to cope with future requirements. In this thesis, we investigate uplink technologies of 3GPP LTE, which is a transmission technique that utilizes single carrier modulation. Single carrier frequency division multiple access (SC-FDMA), a modified form of Orthogonal FDMA (OFDMA), is a promising technique for high data rate uplink communications in future cellular systems. SC-FDMA has similar throughput performance and essentially the same overall complexity as OFDMA. A principal advantage of SC-FDMA is the peak-to-average power ratio (PAPR), which is lower than that of OFDMA. SC-FDMA is currently a strong candidate for the uplink multiple access scheme in the Long Term Evolution of cellular systems under consideration by the Third Generation Partnership Project (3GPP). In our research, We investigate the 3GPP LTE using multiple-input multiple-output (MIMO) and single carrier frequency division multiple access (SC-FDMA) in different carrier mapping schemes to upload technology. We observe MIMO SC-FDMA uses different carrier mapping schemes have different performance. Therefore, We desired that the analysis of MIMO SC-FDMA uses a different carrier mapping schemes, which the best performance of mapping schemes.