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Benner, Peter, and Sabine Hein. "Model predictive control based on an LQG design for time-varying linearizations." Universitätsbibliothek Chemnitz, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-201000221.
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We consider the solution of nonlinear optimal control problems subject to stochastic perturbations with incomplete observations. In particular, we generalize results obtained by Ito and Kunisch in [8] where they consider a receding horizon control (RHC) technique based on linearizing the problem on small intervals. The linear-quadratic optimal control problem for the resulting time-invariant (LTI) problem is then solved using the linear quadratic Gaussian (LQG) design. Here, we allow linearization about an instationary reference trajectory and thus obtain a linear time-varying (LTV) problem on each time horizon. Additionally, we apply a model predictive control (MPC) scheme which can be seen as a generalization of RHC and we allow covariance matrices of the noise processes not equal to the identity. We illustrate the MPC/LQG approach for a three dimensional reaction-diffusion system. In particular, we discuss the benefits of time-varying linearizations over time-invariant ones.
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ABDALLA, TALAL ALMUTAZ ALMANSI. "Recursive Algorithms for Set-Membership Estimation." Doctoral thesis, Politecnico di Torino, 2022. https://hdl.handle.net/11583/2972788.
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Sereni, Bruno. "Static output feedback control for LPV and uncertain LTI systems /." Ilha Solteira, 2019. http://hdl.handle.net/11449/180732.
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Orientador: Edvaldo AssunçãoResumo: Este trabalho aborda o controle via realimentação estática de saída aplicado à sistemas lineares com parâmetro variante (LPV) e lineares incertos invariantes no tempo (LIT). O projeto de ganhos de realimentação estática de saída apresentado neste trabalho é baseado no método dos dois estágios, o qual consiste em primeiramente obter um ganho de realimentação de estados, e então, utilizar esta informação no segundo estágio para obter-se o ganho de realimentação estática de saída desejado. As soluções para os problemas investigados são apresentadas na forma de desigualdades matriciais lineares (no inglês, linear matrix inequalities, LMIs), obtidas por meio da aplicação do Lema de Finsler. Baseado em resultados anteriores encontrados na literatura, este trabalho propõe uma estratégia de relaxação de forma a obter um método menos conservador para obtenção de ganhos robustos de realimentação estática de saída para sistemas incertos LTI. Na estratégia proposta, as variáveis adicionais do Lema de Finsler são consideradas como dependentes de parâmetro, juntamente com o uso de funções de Lyapunov dependentes de parâmetro (no inglês, parameter-dependent Lyapunov functions, PDLFs). É apresentado um estudo avaliando a eficácia da estratégia proposta em fornecer uma maior região de factibilidade para um dado problema. Os resultados foram utilizados em uma comparação com um método de relaxação baseado apenas no uso de PDLFs. Uma segunda contribuição deste trabalho consiste na proposta de um... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The static output feedback (SOF) control applied to linear parameter-varying (LPV) and uncertain linear time-invariant (LTI) systems are addressed in this work. The approach chosen for the design of SOF gains is based on the two-stage method, which consists in obtaining a state feedback gain at first, and then using that information for deriving the desired SOF gain at the second stage. The solutions for the investigated problems are presented in terms of linear matrix inequalities (LMIs), obtained by means of the application of the Finsler's Lemma. Based on previous papers found in literature, this work proposes a relaxation strategy in order to achieve a less conservative method for obtaining robust SOF gains for uncertain LTI systems. In the proposed strategy, the Finsler's Lemma additional variables are considered to be parameter-dependent along with the use of parameter-dependent Lyapunov functions (PDLFs). A study evaluating the effectiveness of the proposed strategy in providing a larger feasibility region for a given problem is presented. The results were used in a comparison with a relaxation method based only on PDLFs. Another contribution of this work lies in the proposal of a solution for the control of LPV systems via the design of a gain-scheduled SOF controller. The methods proposed for both control problems were applied on the design of controllers for an active suspension system. In the experiments, it was assumed that only one of its four system's states wer... (Complete abstract click electronic access below)
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Kounek, Milan. "Model fyzické vrstvy systému LTE." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2013. http://www.nusl.cz/ntk/nusl-220269.
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Master’s thesis deals with the signal processing in LTE system, specifically focuses on the physical layer. The first part describes in detail the signal processing at the physical layer of the LTE system. Based on the acquired knowledge of signal processing is created a block diagram that graphically describes the process of the signal processing. Next part deals with the created mathematical model, which is programmed in Matlab. This section describes the limitations of the model, configuration options and view simulation results. The last part shows the results of simulations and analyzed the results.
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Holmberg, Mattias, and Stefan Hen. "LTA kontra självfall : Ett långsiktigt perspektiv." Thesis, KTH, Byggteknik och design, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-127665.
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Detta arbete syftar till att göra en utvärdering av hur de två skilda spillvattensystemen LTA (Lätt TryckAvlopp) och konventionellt självfallsavlopp står sig mot varandra ur ett långtidsperspektiv. Aspekter så som investering, drift, underhåll, miljöpåverkan, teknik och anläggning har analyserats och sammanställs av denna rapport, samt ett program som beräknar den ekonomiska aspekten mellan respektive system. Programmet, där användaren ges möjligheten att specificera sitt eget område, ger en fingervisning om den lösning som ur ekonomisk aspekt är mest fördelaktig. Detta kombinerat med den kunskap som samlats i rapporten ska leda till ett mer medvetet val hos kommuner och andra VA-huvudmän i Sverige.The purpose of this report is to make a comparison between the two currently used sewage solutions, PSS (Pressure Sewage System) and the more conventional gravity based sewage-system during a vast period of time. Aspects such as investment, maintenance, upkeep, environmental, technology and terrain have been analyzed. The research has resulted in this report and an Excel-program which calculates an estimated economical difference between the two solutions, in a specific case chosen by the user, to determine which is more economically beneficial. This program, used hand in hand with the report, is suppose to increase the knowledgebase regarding the subject of sewage solutions among officials working with these kinds of matters in Sweden.
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Ellenbeck, Jan [Verfasser]. "Radio Resource Management and System Spectral Efficiency in LTE Multi-Cell Systems / Jan Ellenbeck." München : Verlag Dr. Hut, 2015. http://d-nb.info/1076437621/34.
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Ohera, Vlastimil. "Vysokorychlostní mobilní systém LTE." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2009. http://www.nusl.cz/ntk/nusl-218045.
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Aim of thesis was to acquaint with architecture and process of signal in systems using broadband LTE wireless technology. Thesis in detail is described physical layer of system. Next there is described comparison of LTE and WiMAX and table with all present systems. Thesis also is contained information about tested LTE system in real traffic. Next aim was created simulation of LTE system in downlink and uplink. Interface was created for easier configuration of each characteristics of transfer and type of interference of useful signal. This interface is contained control of whole simulation and presentation of measured values. Measured data were processed into graphs, which show dependence of error rate BER on C/N of useful and interference signal.
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Krasowski, Piotr, and Douglas Troha. "Wireless system design : NB-IoT downlink simulator." Thesis, Uppsala universitet, Signaler och System, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-317877.
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The newly defined NB-IoT standard currently lacks a toolkit and simulator. In order to develop algorithms for this new standard there is a need for channels and signals as reference during tests. MATLAB is commonly used for testing LTE signals and therefore the toolkit was developed in this environment. The toolkit focuses primarily on the Layer 1-relevant functionality of NB-IoT, the grid generation, encoding, rate-matching and modulation of channels. The simulator focuses on testing the developed toolkit in a virtual LTE NB-IoT environment. The virtual environment attempts to emulate a base station and a terminal. The path followed is scheduling, channel processing, grid generation, QPSK and OFDM modulation through a modeled channel, OFDM demodulation, channel estimation, equalisation, QPSK demodulation and reversal of channel processing. The simulator tests primarily the NPDSCH channel implementations. Measurements of bit error and block error rates were made and it was concluded that they follow the expected trends. More testing is required to validate the remaining channels. A sector equaliser and an interpolating equaliser were tested by measuring block error rate and checking constellation diagrams and it was concluded that the performance of the interpolation equaliser is more consistent. In order to improve the equalisation further the noise estimation must be reworked.
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Praveen, Vunnam. "Maximizing LTE performance with MIMO Systems." Thesis, Linnéuniversitetet, Institutionen för fysik och elektroteknik (IFE), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-58272.
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The project explains Long Term Evolution (LTE) systems when used with Multiple-Input, MultipleOutput (MIMO) fulfill the growing demands in throughput and system robustness for the user. This is investigated by understanding the throughput capacity of LTE down-links in both spatial multiplexing and transmission diversity mode. The performance downgrades in LTE frame is analyzed. All the simulations are done in MATLAB. The simulations include Bit Error Rate (BER) being verified for values of Signal to Noise Ratio (SNR). MIMO systems use more than one antenna configuration for sending and receiving radio signals of the same frequency. The concept of beam forming may be utilized by MIMO systems. This is done by employing more than one antenna at both the ends namely transmitter (Tx) and receiver (Rx). The use of multiple antennas will achieve higher capacity and better cell coverage. MIMO technologies, when used in LTE, provide better down-link peak rates, cell coverage, and enhanced average cell throughput. LTE offers increased capacity while using standard antenna technique. This technique provides two vital aspects namely, spatial multiplexing (SM) and transmits diversity (TD). The project also explores the effect of different parameters namely, the speed of mobile station, the number of Multipath, Rician factor (K) on throughput is discussed and reported. The report evaluates the performance of LTE using MIMO in order to explain LTE system capacity, average cell throughput of LTE at different bandwidths and BER performance against SNR. The simulation outputs are shown as graphs and discussed.
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Al-Dulaimi, Anwer. "Cognitive radio systems in LTE networks." Thesis, Brunel University, 2012. http://bura.brunel.ac.uk/handle/2438/11544.
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The most important fact in the mobile industry at the moment is that demand for wireless services will continue to expand in the coming years. Therefore, it is vital to find more spectrums through cognitive radios for the growing numbers of services and users. However, the spectrum reallocations, enhanced receivers, shared use, or secondary markets-will not likely, by themselves or in combination, meet the real exponential increases in demand for wireless resources. Network operators will also need to re-examine network architecture, and consider integrating the fibre and wireless networks to address this issue. This thesis involves driving fibre deeper into cognitive networks, deploying microcells connected through fibre infrastructure to the backbone LTE networks, and developing the algorithms for diverting calls between the wireless and fibre systems, introducing new coexistence models, and mobility management. This research addresses the network deployment scenarios to a microcell-aided cognitive network, specifically slicing the spectrum spatially and providing reliable coverage at either tier. The goal of this research is to propose new method of decentralized-to-distributed management techniques that overcomes the spectrum unavailability barrier overhead in ongoing and future deployments of multi-tiered cognitive network architectures. Such adjustments will propose new opportunities in cognitive radio-to-fibre systematic investment strategies. Specific contributions include: 1) Identifying the radio access technologies and radio over fibre solution for cognitive network infrastructure to increase the uplink capacity analysis in two-tier networks. 2) Coexistence of macro and microcells are studied to propose a roadmap for optimising the deployment of cognitive microcells inside LTE macrocells in the case of considering radio over fibre access systems. 3) New method for roaming mobiles moving between microcells and macrocell coverage areas is proposed for managing spectrum handover, operator database, authentication and accounting by introducing the channel assigning agent entity. The ultimate goal is to reduce unnecessary channel adaptations.
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Abdulhameed, Abbas Abdulazeez. "Combining SysML and SystemC to Simulate and Verify Complex Systems." Thesis, Besançon, 2016. http://www.theses.fr/2016BESA2045/document.
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De nombreux systèmes hétérogènes sont complexes et critiques. Ces systèmes intègrent du logiciel et des composants matériels avec des interactions fortes entre ces composants. Dans ce contexte, il est devenu absolument nécessaire de développer des méthodologies et des techniques pour spéciier et valider ces systèmes.Dans l'ingénierie des systèmes, les exigences sont l'expression des besoins qu'un produit spécifique ou un service doit réaliser. Elles sont définies formellement à de nombreuses occasions dans l'ingénierie des systèmes complexes. Dans ce type de système, deux catégories d'exigence sont présentes : les exigences non-fonctionnelles telles que la performance et la fiabilité, les exigences fonctionnelles telles que la vivacité. Pour valider ces exigences, un environnement permettant de simuler et vérifier ces propriétés est essentiel.Dans notre travail, nous proposons une méthodologie basée sur SysML et combinée avec SystemC et Promela/SPIN pour spéciier et valider des systèmes complexes. Cette approche est basée sur l'ingénierie dirigée par les modèles pour premièrement traduire des modèles SysML en SystemC afin de réaliser des simulations et deuxièmement traduire des diagrammes d'état SysML en Promela/SPINain de vérifier des propriétés temporelles extraites des exigences. Cette approche est expérimentée sur une étude de cas pour démontrer sa faisabilitéHeterogeneous Systems are complex and become very critical. These systems integrate software andhardware components with intensive interaction between them. In this context, there is a strongnecessity to develop methodologies and techniques to specify and validate these systems.In engineering, the requirements are the expression of needs on what a particular product or a serviceshould be or to make. They are used most of the time in a formal sense in the systems engineering.In this kind of systems, several types of requirements are present: non-functional requirements suchas the performance and the reliability and functional requirements such as the liveliness. To validatethese requirements of a system, an environment to simulate and to check the properties is essential.In our work, we propose a methodology based on SysML combined with SystemC and Promela/SPINto specify and validate complex systems. This approach is based on Model Driven Engineeringtechniques to irstly translate SysML models to systemC with the aim of simulation and to mapSysML behavioral diagrams to Promela/SPIN in order to verify temporal properties extracted fromthe requirements. The approach is experimented on case studies to demonstrate its feasibility
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Hu, Yiran. "Identification and State Estimation for Linear Parameter Varying Systems with Application to Battery Management System Design." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1281368350.
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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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Li, Wei. "Performance enhancement for LTE and beyond systems." Thesis, University of Bedfordshire, 2014. http://hdl.handle.net/10547/576455.
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Wireless communication systems have undergone fast development in recent years. Based on GSM/EDGE and UMTS/HSPA, the 3rd Generation Partnership Project (3GPP) specified the Long Term Evolution (LTE) standard to cope with rapidly increasing demands, including capacity, coverage, and data rate. To achieve this goal, several key techniques have been adopted by LTE, such as Multiple-Input and Multiple-Output (MIMO), Orthogonal Frequency-Division Multiplexing (OFDM), and heterogeneous network (HetNet). However, there are some inherent drawbacks regarding these techniques. Direct conversion architecture is adopted to provide a simple, low cost transmitter solution. The problem of I/Q imbalance arises due to the imperfection of circuit components; the orthogonality of OFDM is vulnerable to carrier frequency offset (CFO) and sampling frequency offset (SFO). The doubly selective channel can also severely deteriorate the receiver performance. In addition, the deployment of Heterogeneous Network (HetNet), which permits the co-existence of macro and pico cells, incurs inter-cell interference for cell edge users. The impact of these factors then results in significant degradation in relation to system performance. This dissertation aims to investigate the key techniques which can be used to mitigate the above problems. First, I/Q imbalance for the wideband transmitter is studied and a self-IQ-demodulation based compensation scheme for frequency-dependent (FD) I/Q imbalance is proposed. This combats the FD I/Q imbalance by using the internal diode of the transmitter and a specially designed test signal without any external calibration instruments or internal low-IF feedback path. The instrument test results show that the proposed scheme can enhance signal quality by 10 dB in terms of image rejection ratio (IRR). In addition to the I/Q imbalance, the system suffers from CFO, SFO and frequency-time selective channel. To mitigate this, a hybrid optimum OFDM receiver with decision feedback equalizer (DFE) to cope with the CFO, SFO and doubly selective channel. The algorithm firstly estimates the CFO and channel frequency response (CFR) in the coarse estimation, with the help of hybrid classical timing and frequency synchronization algorithms. Afterwards, a pilot-aided polynomial interpolation channel estimation, combined with a low complexity DFE scheme, based on minimum mean squared error (MMSE) criteria, is developed to alleviate the impact of the residual SFO, CFO, and Doppler effect. A subspace-based signal-to-noise ratio (SNR) estimation algorithm is proposed to estimate the SNR in the doubly selective channel. This provides prior knowledge for MMSE-DFE and automatic modulation and coding (AMC). Simulation results show that this proposed estimation algorithm significantly improves the system performance. In order to speed up algorithm verification process, an FPGA based co-simulation is developed. Inter-cell interference caused by the co-existence of macro and pico cells has a big impact on system performance. Although an almost blank subframe (ABS) is proposed to mitigate this problem, the residual control signal in the ABS still inevitably causes interference. Hence, a cell-specific reference signal (CRS) interference cancellation algorithm, utilizing the information in the ABS, is proposed. First, the timing and carrier frequency offset of the interference signal is compensated by utilizing the cross-correlation properties of the synchronization signal. Afterwards, the reference signal is generated locally and channel response is estimated by making use of channel statistics. Then, the interference signal is reconstructed based on the previous estimate of the channel, timing and carrier frequency offset. The interference is mitigated by subtracting the estimation of the interference signal and LLR puncturing. The block error rate (BLER) performance of the signal is notably improved by this algorithm, according to the simulation results of different channel scenarios. The proposed techniques provide low cost, low complexity solutions for LTE and beyond systems. The simulation and measurements show good overall system performance can be achieved.
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Bawab, Hiba. "Power allocation in overlaid DVB-LTE systems." Thesis, Rennes, INSA, 2015. http://www.theses.fr/2015ISAR0038/document.
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L'avènement de terminaux avancés permet l'accès à des services toujours plus gourmands en bande passante, avec notamment le déploiement de services de vidéo mobile sans couture offert par le mode diffusion mobile intégré standardisé par le 3GPP. Dans le même temps, la communauté << broadcast » s'est adaptée aux nouveaux usages de télévision mobile avec la norme DVB-NGH (Digital Video Broadcasting - Next Generation Handheld). Dans ce contexte, l'objectif de cette thèse est d'étudier la convergence spectrale entre les deux réseaux DVB et LTE en déployant une petite cellule LTE au sein d'une grande cellule DVB. Les deux technologies utilisent une forme d'onde OFDM (Orthogonal Frequency Division Multiplexing), en liaison descendante pour le LTE, ct possèdent donc quelques similarités tout en étant assez différentes par leurs caractéristiques. Dans ces travaux, nous nous intéressons aux performances atteignables lorsque les deux systèmes se recouvrent spectralement sans coopération. Le problème considéré étant analogue à un problème d’utilisateur secondaire opérant en mode recouvrement avec un utilisateur primaire, on commence par étudier le problème de la capacité ergodique du système secondaire, i.e. utilisateur LTE, sous contraintes de puissance moyenne générée par le secondaire sur le primaire, i.e LTE sur DVB, et de puissance crête au secondaire lorsque l'utilisateur primaire interfère sur le secondaire. Le problème est résolu analytiquement dans le cas général du canal croisé avec évanouissements de Rayleigh. Dans un deuxième temps nous étendons cette étude préliminaire au cas où la forme d'onde des deux systèmes primaire et secondaire est effectivement de type OFDM. En considérant d'abord un modèle simple de recouvrement total des sous-porteuses, nous délivrons la capacité ergodique globale ce qui nous permet d'évaluer l'influence des paramètres des systèmes, comme le nombre de sous-porteuses de chaque système ou les puissances interférentes, sur les capacités globales et individuelles. Nous nous intéressons ensuite à l'optimisation de la capacité globale où deux stratégies sont étudiées. D'une part, la capacité globale étant la somme de deux fonctions convexe et concave respectivement, la solution obtenue conduit au minimum de capacité globale mais mène à une situation d'équilibre entre les systèmes DVB et LTE. D'autre part, la maximisation de la capacité globale sous contrainte conduit à favoriser largement un système sur l'autre. Enfin, une étude fine de l'interférence causée par un système sur l'autre par recouvrement partiel est menée. L'effet de la variation du taux de recouvrement spectral entre les bandes du DVB et du LTE sur l'efficacité spectrale globale est étudié. On suppose ensuite que le récepteur possède une capacité de réjection de l'interférence permettant de déterminer le recouvrement optimal maximisant la capacité globale. Les différentes contributions de ces travaux ont permis d'avoir une approche théorique sur la modalité d'allocation de puissance des deux systèmes DVB et LTE co-existants et sur le taux de recouvrement approprié entre leurs spectres respectifs. Cette étude pourrait être ut le pour les opérateurs intéressés par un scénario de déploiement dense afin de choisir les configurations optimales des ressources dans une perspective de réutilisation agressive des fréquencesSince the launch of the first numerical mobile telecommunications networks in the nineties, the quantity of the transmitted data over the networks is increasing year by year. Advanced user equipments enable to implement more and more bandwidth consuming services such as mobile T and multimedia internet, available in the integreted mobile broadcast mode recently standardized by the 3GPP group. In the meanwhile, the digital vide broadcasting - next generation handled (DVB-NGH) has been released in order to satisfy the increasing demand for mobile TV. These technologies compete for a more and more constrained spectral resource leading to question the possibility to deploy DVB and Long Term Evolution (LTE) service in a spectral overlay mode as it has been investigated by the Ml project funded by the National Research Agency. In this context, this thesis aims at studying the spectral convergence between DVB and LTE networks by deploying a small LTE cell in a large DVB cell. Both technologies present some similarities, i.e. both use orthogonal frequency division multiplexing (OFDM) waveform (in downlink for LTE), but technical characteristics remain rather different between those. In this work, we deal with achievable performance when DVB and LTE spectrally overlap without cooperation. The considered problem being analog to the Seconda1y User (SU) - Primary User (PU) coexistence in overlay scenario, the SU ergodic capacity under average power generated on PU and peak power at SU constaints is investigated. An analytic solution is proposed in X-Channel with Rayleigh fading. In a second time, SU and PU are considered to be LTE and DVB respectively with their particular OFDM signal characteristics. With a first model of overlapping subcarriers, LTE and DVB ergodic capacities and global capacity as well are derived in closed form allowing to study the influence of several system parameters on ergodic capacities. The global capacity is then optimized using a convex-concave procedure leading to the minimum on the global capacity but to balanced capacity on individual links. On a second hand, global capacity maximization leads to favor one system over the other. Last but not least, a careful study of the interference caused by one system over the other by partial overlay is led. The effect of spectral overlap ratio between DVB and LTE systems over the global spectral efficiency is investigated. Advanced interference rejection ability is then assumed at receivers and the optimal spectral overlap, i.e. maximizing the global capacity, is then derived in that case. The different contributions in this work give a theoretical approach on the power allocation modality of two coexisting DVB and LTE systems and on the appropriate spectral overlap ratio between their respective spectrums. This study can be useful for operators interested in dense network deployment scenarios to decide the operating point of allocated resources in a very aggressive frequency reuse pattern
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Defibaugh, June, and Norman Anderson. "National Guard Data Relay and the LAV Sensor System." International Foundation for Telemetering, 1996. http://hdl.handle.net/10150/611416.
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International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, CaliforniaThe Defense Evaluation Support Activity (DESA) is an independent Office of the Secretary of Defense (OSD) activity that provides tailored evaluation support to government organizations. DESA provides quick-response support capabilities and performs activities ranging from studies to large-scale field activities that include deployment, instrumentation, site setup, event execution, analysis and report writing. The National Guard Bureau requested DESA's assistance in the development and field testing of the Light Armored Vehicle (LAV) Sensor Suite (LSS). LSS was integrated by DESA to provide a multi-sensor suite that detects and identifies ground targets on foot or in vehicles with minimal operator workload. The LSS was designed primarily for deployment in high density drug trafficking areas along the northern and southern borders using primarily commercial-off-the-shelf and government-off-the-shelf equipment. Field testing of the system prototype in summer of 1995 indicates that the LSS will provide a significant new data collection and transfer capability to the National Guard in control of illegal drug transfer across the U.S. borders.
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Khwandah, Sinan. "System optimisation and radio planning for future LTE-advanced." Thesis, Brunel University, 2015. http://bura.brunel.ac.uk/handle/2438/13822.
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This work is related to wireless communication. In this Thesis three main issues are addressed for future cellular networks: power consumption, interference and mobility. These issues continue to be a burden on the system’s performance as long as technology keeps evolving. In the presented chapters, the focus was to introduce greater intelligence to the LTE system algorithms and bring to them a dynamic and self-organizing approach. The first approach concerns power consumption in wireless terminals. The currently applied solution to save energy is the DRX mechanism. It organizes the time when the terminal wakes up and starts receiving data, and when it goes into sleep mode in order to save its battery power. The current DRX is described as static or fixed which makes its parameters unsuitable for the nature of the bursty traffic. In this work an adaptive DRX mechanism is proposed and evaluated as the wireless terminal battery saving algorithm. The second approach is co-channel interference mitigation. To increase the system’s capacity and avoid spectrum scarcity, small cells such as Femtocells are deployed and operate on the same frequency bands as the Macrocell. Although these small nodes increase the system capacity, however, the challenges will be in the femtocells planning and management in addition to the interference issues. Here a dynamic interference cancellation approach is presented to enable the Femtocell to track the allocated resources to the Macro-users, and to avoid using them. The third approach concerns mobility management in heterogeneous networks. The wireless terminal may have different mobility levels during handover which increases the handover failures due to failure in handover commands and aging of the reported parameters. This issue is presented in detail with the aim to avoid performance degradation and improve the reporting mechanisms during fast mobility levels. For this regard the presented method proposes more cooperation between the serving cell and the end-user so that the large amount of overhead and measurement are reduced. Simulations with different configurations are conducted to present the results of the proposed models. Results show that the proposed models bring improvements to the LTE system. The enhanced self-organized architecture in the three presented approaches performs well in terms of power saving, dynamic spectrum utilization by Femtocells, and mitigation of sudden throughput degradation due to the serving cell’s downlink signal outage during mobility.
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Dias, Pedro António Figueiredo. "Processing techniques with multiple antennas for the LTE system." Master's thesis, Universidade de Aveiro, 2012. http://hdl.handle.net/10773/10917.
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Mestrado em Engenharia Electrónica e TelecomunicaçõesPerformance, mobilidade e partilha podem ser consideras como as três palavras-chave nas comunicações móveis de hoje em dia. Uma das necessidades fundamentais do ser humano é a partilha de experiencias e informação. Com a evolução ao nível do hardware móvel, a crescente popularidade de smartphones, tablets e outros dispositivos moveis, fez com que a exigência em termos de capacidade e taxa de transferência por parte das redes móveis não parasse de crescer. As limitações das redes 3G fizeram com que não conseguissem corresponder a tais exigências e como tal, a transição para uma tecnologia mais robusta e eficiente passou a ser inevitável. A resposta escolhida como solução a longo prazo é a rede designada por LTE, desenvolvida pela organização 3GPP é assumido que será a rede de telecomunicações predominante no futuro. As vantagens mais sonantes são, naturalmente, elevadas taxas de transmissão, maior eficiência espectral, redução da latência e de custos de operação. As principais tecnologias em que o LTE se baseia, são o OFDM e sua variante para múltiplo acesso, OFDMA, usado para o downlink e o SC-FDMA para o uplink. Além disso, usa sistemas com múltiplas antenas para impulsionar a eficiência espectral. Apesar de já implementado em alguns países por diversas operadoras, constantes pesquisas continuam a ser realizadas com o intuito de melhorar a sua performance. Nesta dissertação é proposto um esquema duplo de codificação na frequência e no espaço (D-SFBC) para um cenário baseado em OFDM com 4 antenas de transmissão e duas antenas de recepção (4 × 2 D-SFBC) para o downlink. No cenário considerado, 4 símbolos de dados são transmitidos utilizando unicamente 2 sub-portadoras, fazendo com que, este sistema seja limitado pela interferência. Para de forma eficiente descodificar os símbolos de dados transmitidos, foi desenvolvido um equalizador iterativo no domínio da frequência. Duas abordagens são consideradas: cancelamento da interferência em paralelo (PIC) e sucessivo cancelamento de interferência (SIC). Uma vez que apenas 2 sub-portadoras são usadas para transmitir quatro símbolos de dados em paralelo, o esquema desenvolvido duplica a taxa de dados quando comparado com o esquema 2 × 2 SFBC, especificado no standard do LTE. Os esquemas desenvolvidos foram avaliados sob as especificações para LTE e usando codificação de canal. Os resultados mostram que os esquemas implementados neste trabalho utilizando um equalizador iterativo supera os convencionais equalizadores lineares na eliminação da interferência adicional introduzida, em apenas 2 ou 3 iterações.
Performance, mobility and sharing can be assumed as the three keywords in the mobile communications nowadays. One of the fundamental needs of human beings is to share experiences and information. With the evolution of mobile hardware level, the growing popularity of smartphones, tablets and other mobile devices, has made that the demand in terms of capacity and throughput by mobile networks did not stop growing. Thus, the limitations of 3G stops it of being the answer of such demand, and a transition to a powerful technology has become unavoidable. The answer chosen is LTE, developed by the 3GPP organization is assumed to be the predominant telecommunications network in the future. The most relevant advantages are high transmission rates, higher spectral efficiency, reducing latency and operating costs. The key technologies in which LTE is based, are OFDM and its variant schemes for multiple access, OFDMA, used for downlink, and SC-FDMA for the uplink. It also uses multiple antennas systems in order to improve spectral efficiency. Although already implemented in some countries by several operators, continuous research is conducted in order to improve their performance. In this dissertation it is proposed a double space-frequency block coding (D-SFBC) scheme for an OFDM based scenario with 4 transmit antennas and 2 receive antennas (4×2 D-SFBC) for the downlink. In the considered scenario, 4 data symbols are transmitted by using only 2 subcarriers and thus the system is interference limited. To efficiently decode the transmitted data symbols an iterative equalizer designed in frequency domain is developed. Two approaches are considered: parallel interference cancellation (PIC) and successive interference cancellation (SIC). Since only 2 subcarriers are used to transmit 4 data symbols in parallel the developed scheme achieve the double data rate when compared with the 2×2 SFBC, specified in the LTE standard. The developed schemes were evaluated under the main LTE specifications and using channel coding. The results have show that the schemes implemented in this work using an interactive equalizer outperforms the conventional linear equalizers in the interference removal, just by using 2 or 3 iterations.
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Lehtisalo, V. (Ville). "Average power tracking optimization system for LTE power amplifiers." Master's thesis, University of Oulu, 2014. http://jultika.oulu.fi/Record/nbnfioulu-201409171871.
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Abstract. This thesis introduces the design and implementation of an optimization system for average power tracking, used in the RF power amplifier of LTE mobile device. Average power tracking adjusts the supplied voltage of the power amplifier according to output power level so that the linearity of the power amplifier is maintained while the efficiency is improved. The optimization system is implemented with computer controlled measurement equipment setup. The setup consists of an RF signal generator, a power meter and a spectrum analyzer.
Performance measurements are performed to the device under test with different bias voltages of the PA and various output power levels, separately for two different power modes of the power amplifier. The performance measurements focus on the ratio of transmission channel power and adjacent channel power. Total efficiency and gain of the device and the current consumption of the power amplifier were also measured.
Based on the measurement results, the most suitable voltage for the power amplifier can be selected for each power level with a voltage table optimizing algorithm. The algorithm compares the measured adjacent channel leakage ratio to a predetermined target value and selects the lowest linearity requirements fulfilling a voltage value for the power amplifier. The effects of output power and supplied voltage on the linearity, gain and efficiency of the device are observed. The results show that the performance of the device under test is greatly dependent on the bias voltage of the power amplifier.
In addition, the effect of ambient temperature and different frequency channels on the linearity and gain are observed. The measurements show that the temperature affects marginally the gain whereas linearity is more dependent on the used frequency channel.
Finally the suitability of the optimized bias voltage table is verified by using it to adjust the power amplifier of a separate test board. The linearity of the product is verified by measuring the adjacent channel leakage ratio and comparing it to official requirements.
The voltage table generated with the optimizing algorithm based on the results obtained with the measurement setup is well suited for improving the power amplifier efficiency with average power tracking. It is a fast method to obtain a wide range of measurement results of the performance of a power amplifier with various output power levels and bias voltages.Keskimääräisen tehonseurannan optimointisysteemi LTE-tehovahvistimille. Tiivistelmä. Tässä diplomityössä esitellään LTE-tiedonsiirtotekniikkaa tukevassa matkapuhelimessa käytettävän RF-tehovahvistimen keskimääräisen tehonseurannan optimointisysteemin suunnittelu ja toteutus. Keskimääräinen tehonseuranta säätää tehovahvistimen käyttöjännitettä lähtötehon perusteella niin, että tehovahvistimen lineaarisuus säilytetään ja hyötysuhde paranee. Optimointisysteemi toteutettiin tietokone-ohjatulla mittalaitekokoonpanolla sekä tulostenkäsittelyalgoritmilla. Mittalaitekokoonpano koostuu RF-signaaligeneraattorista, tehomittarista ja spektrianalysaattorista.
Testilaitteelle suoritetaan suorituskykymittauksia eri tehovahvistimen jännitearvoilla ja usealla lähtötehotasolla, erikseen kahdelle eri vahvistimen tehotilalle. Suorituskykymittaukset keskittyvät lähetyskanavan sekä viereisen kanavan tehon suhteen mittaukseen. Myös hyötysuhde, kokonaisvahvistus sekä testilaitteen tehovahvistimen virrankulutus mitataan suorituskykymittausten yhteydessä.
Mittaustulosten perusteella jännitetaulukon optimointialgoritmilla saadaan valittua sopivin tehovahvistimelle syötettävä jännite kullekin lähtötehotasolle. Algoritmi vertaa viereisen kanavan vuototehon suuruutta asetettuun tavoitearvoon ja valitsee tehovahvistimelle matalimman lineaarisuusvaatimukset täyttävän jännitteen. Havaintoja tehdään testilaitteen tehovahvistimen lineaarisuuden, vahvistuskertoimen ja hyötysuhteen riippuvuudesta lähtötehoon sekä käyttöjännitteeseen. Tuloksista nähdään syötettävän jännitteen vaikuttavan voimakkaasti testilaitteen suorituskykyyn.
Myös ympäröivän lämpötilan sekä taajuuskanavan vaikutusta tehovahvistimen lineaarisuuteen ja vahvistuskertoimeen tutkitaan. Mittaukset osoittavat lämpötilan vaikuttavan tehovahvistimen vahvistuskertoimeen marginaalisesti. Sen sijaan lineaarisuuteen vaikuttaa enemmän käytettävä taajuuskanava.
Lopuksi optimoidun jännitetaulukon soveltuvuus varmistetaan käyttämällä sitä erillisellä testilevyllä tehovahvistimen jännitteen säätämiseen. Varmistusmittauksissa lineaarisuus testataan mittaamalla viereisen kanavan vuototehon suuruus ja vertaamalla sitä asetettuihin virallisiin vaatimuksiin.
Mittalaitekokoonpanolla saatujen mittaustulosten sekä optimointialgoritmin perusteella luotu jännitetaulukko soveltuu hyvin tehovahvistimen hyötysuhteen parantamiseen keskimääräisen tehonseurannan avulla. Se on nopea tapa saada mittaustuloksia tehovahvistimen suorituskyvystä laajalta lähtötehoalueelta eri jännitearvoilla.
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Langlais, Valentin. "Contrôle de l'activité des récepteurs NMDA par la D-sérine : rôle des récepteurs astrocytaires EphB3 et CB1." Thesis, Bordeaux, 2016. http://www.theses.fr/2016BORD0211/document.
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Les astrocytes sont des partenaires clés des neurones. Dans l’hippocampe, et tout particulièrement au niveau des synapses CA3-CA1, en libérant la D-sérine, ces cellules gliales régulent l’activité des récepteurs glutamatergiques de type N-methyl-D-aspartate (NMDA) et de ce fait la mémoire synaptique, aussi connue sous le nom de plasticité synaptique à long terme. Cependant, le signal synaptique à l’origine de la libération de la D-sérine par les astrocytes reste à ce jour méconnu. De par des données rapportées dans la littérature nous nous sommes tout particulièrement intéressés aux récepteurs astrocytaires aux ephrins de type B3 (EphB3) et aux endocannabinoïdes de type 1 (CB1). Pour ce faire nous avons principalement utilisé une approche électrophysiologique sur des tranches aiguës d’hippocampe de souris adulte. Dans une première étude, nos données indiquent que l’activation des récepteurs EphB3 augmente la présence de D-sérine synaptique et en conséquence l’activité des récepteurs NMDA synaptiques. A l’inverse, leur inhibition diminue à la fois l’activité des récepteurs NMDA synaptiques et la potentialisation à long-terme qui en dépend (LTP ; une forme de plasticité synaptique à long terme). L’interaction EphB3-ephrinB3 contrôle donc la LTP en contrôlant la disponibilité en D-sérine synaptique. Dans une seconde étude, nous avons utilisé un modèle transgénique permettant d’inhiber l’expression des récepteurs CB1 astrocytaires (souris GFAP-CB1-KO). Nous avons découvert que la suppression de ces récepteurs diminue la disponibilité en D-sérine synaptique. De plus, nos travaux montrent que les récepteurs CB1 astrocytaires sont nécessaires à l’induction de la LTP via la D-serine. En conclusion, ces travaux de Thèse révèlent que les récepteurs astrocytaires EphB3 et CB1 régulent les fonctions dépendantes des récepteurs NMDA via le contrôle qu’ils exercent sur la disponibilité en D-sérineAstrocytes are key partners of neurons. In the hippocampus, and more particularly at CA3-CA1 synapses, by releasing D-serine, these glial cells regulate the activity of synaptic Nmethyl-D-aspartate (NMDA) receptors and thus synaptic memory, also known as long-term synaptic plasticity. Yet, the synaptic signal inducing D-serine release by astrocytes is still unknown. Based on interesting data from the literature we have investigated the role of the astrocytic receptors for ephrinB3 (EphB3) and endocannabinoids (CB1). To this end we used electrophysiological approaches on acute hippocampal slices of adult mice. In a first study, our data indicate on one hand that the activation of EphB3 receptors increases synaptic D-serine availability and in consequences the activity of synaptic NMDA receptor activity. On the other hand, inhibition of EphB3 receptors induces a decrease of synaptic NMDA receptor activity as well as the induction of the long-term potentiation (LTP; a form of long-term plasticity). Thus, EphB3-ephrinB3 interaction controls LTP induction through the availability of synaptic D-serine. In a second study, we used a transgenic model allowing the inhibition of CB1 receptors expression in astrocytes (GFAP-CB1-KO mice). We discovered that their deletion reduced synaptic D-serine availability. Our work shows that astrocytic CB1 receptors are necessary for LTP induction via this D-serine. All together, this PhD work reveals that astrocytic EphB3 and CB1 receptors regulate synaptic NMDA receptor functions through the control of D-serine availability
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Babun, Leonardo. "Extended Coverage for Public Safety and Critical Communications Using Multi-hop and D2D Communications." FIU Digital Commons, 2015. http://digitalcommons.fiu.edu/etd/1920.
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In this thesis, we proposed the use of device-to-device (D2D) communications for extending the coverage area of active base stations, for public safety communications with partial coverage. A 3GPP standard compliant D2D system level simulator is developed for HetNets and public safety scenarios and used to evaluate the performance of D2D discovery and communications underlying cellular networks. For D2D discovery, the benefits of time-domain inter-cell interference coordi- nation (ICIC) approaches by using almost blank subframes were evaluated. Also, the use of multi-hop is proposed to improve, even further, the performance of the D2D discovery process. Finally, the possibility of using multi-hop D2D communications for extending the coverage area of active base stations was evaluated. Improvements in energy and spectral efficiency, when compared with the case of direct UE-eNB communi- cations, were demonstrated. Moreover, UE power control techniques were applied to reduce the effects of interference from neighboring D2D links.
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Fuentes, Jose L. S. M. Massachusetts Institute of Technology. "Commercial Aircraft Corporation of China (Comac) attempts to break the Airbus-Boeing duopoly, will it succeed? : an industry analysis framework applied." Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/70829.
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Thesis (S.M. in Engineering and Management)--Massachusetts Institute of Technology, Engineering Systems Division, System Design and Management Program, 2011.Page 88 blank. Cataloged from PDF version of thesis.
Includes bibliographical references (p. 82-87).
Using an industry analysis framework, this thesis analyzes whether the recently established Commercial Aircraft Corporation of China (Comac) is likely to break the Boeing-Airbus duopoly in the industry of large commercial airplanes. The selected framework for this thesis is comprised by the following two principles: 1) "The nature and degree of competition in an industry hinge on five forces, one of these being the Threat of New Entrants, which depends on the height of Entry Barriers." (Porter 1979, 1) 2) "In order to cope with the competitive forces in an industry, there are three potentially successful generic strategic approaches to outperforming other firms in the industry: overall cost leadership, differentiation, and focus." (Porter 1980, 35) The results from the barriers of entry analysis suggest that Comac enjoys full unconditional support from the Chinese government as the development of an aerospace industry is deemed as national interest. However, the firm faces a high barrier of entry derived from the advantages the incumbent companies have in terms of their learning and experience curves, which allow them to effectively conduct research and development and innovate. In the long run, as the companies seek sustained competitive advantage (Porter 1984, 34), I find that Comac will mainly rely on generic strategy 'cost', while the incumbents counteract by adopting mainly generic strategy 'differentiation' and 'focus'. This thesis claims the chances of success for Comac largely depend not only on finding the right strategy for a proper balance between 'cost' and 'differentiation', but mainly on the Chinese government being able to maintain protectionist policies in place. In other words, the Chinese government must continue to decide for the domestic airlines what airplanes they should buy. This conclusion is reached by analyzing the history of all previous attempts by China to develop a national jet-which have all been unsuccessful- and the recent history of high-tech industries where China represented the world's largest market and there was a national interest for technology transfer.
by Jose L. Fuentes.
S.M.in Engineering and Management
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Veloso, de Aguiar Guilherme, and Mark Anderson Woolard. "Estimating carbon emissions from less-than-truckload (LTL) shipments." Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/92121.
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Thesis: M. Eng. in Logistics, Massachusetts Institute of Technology, Engineering Systems Division, 2014.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 86-88).
Less-than-truckload (LTL) is a $32-billion sector of the trucking industry that focuses on moving smaller shipments, typically with weights between 100 and 10,000 pounds, that do not require a full trailer to be moved. Currently, there are no widely accepted methods to estimate carbon emissions from LTL shipments which take into account all the complexities of a typical LTL network. This thesis seeks to address this issue by suggesting a methodology that allows different parties to estimate the emissions of individual LTL shipments with minimal input information. Throughout this research, we worked with C. H. Robinson, a Third-Party Logistics Provider (3PL), and Estes Express Lines, a privately-owned freight transportation company, and analyzed more than 1.5 million shipments. We developed two calculation tools: a detailed model, specifically designed for and based on Estes Express' network and operations, and a lower-precision generic model, adapted from the detailed one so that it could be applied to carriers whose network characteristics are unknown. We also assessed current estimation methods and found that they tend to underestimate the emissions from LTL shipments primarily because (1) they rely on direct over-the-road distances as opposed to actual shipped distances, which must include the intermediate stops, and (2) they fail to factor in the pick-up and delivery (P&D) sections, focusing solely on line haul operations. Therefore, while existing initiatives such as the GHG Protocol and the EPA SmartWay program provide guidance on how to estimate carbon emissions from transportation in general, the LTL industry still needs a specific approach that takes into account all of its unique characteristics. This thesis provides a contribution in that direction by suggesting a methodology to better estimate the carbon emissions of individual LTL shipments.
by Guilherme Veloso de Aguiar and Mark Anderson Woolard.
M. Eng. in Logistics
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Machinek, Marian. ""Das Gesetz des Lebens ?" : die Auslegung der Bergpredigt bei L. N. Tolstoj im Kontext seines ethisch-Religiösen Systems /." Sankt-Ottilien : Eos Verlag, 1998. http://catalogue.bnf.fr/ark:/12148/cb39004163r.
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Zhang, Sina. "Inter-cell Interference Coordination in Indoor LTE Systems." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-91849.
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Inter-cell interference coordination in 3GPP Long Term Evolution system received much attention in recent years. However, most of the studies are based on ideal system with regular hexagon-shaped cell. The indoor environment has special characteristics that the building shape and BS locations are irregular; the traffic load has great variation compared to urban and rural area. So, conventional ICIC scheme may not be used in indoor situation directly. In this thesis, ICIC scheme is employed for indoor environment. Based on different quality of backhaul, static and dynamic schemes will be proposed. The performances of proposed schemes and the performance of system without ICIC will be simulated and compared. At last, how much the improvement of the system can acquire after applying ICIC schemes will be analyzed, and the question about whether it is good to apply ICIC scheme in indoor environment will be answered.
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Al-Rubaye, Saba. "Radio network management in cognitive LTE-femtocell Systems." Thesis, Brunel University, 2013. http://bura.brunel.ac.uk/handle/2438/11827.
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There is a strong uptake of femtocell deployment as small cell application platforms in the upcoming LTE networks. In such two-tier networks of LTE-femtocell base stations, a large portion of the assigned spectrum is used sporadically leading to underutilisation of valuable frequency resources. Novel spectrum access techniques are necessary to solve these current spectrum inefficiency problems. Therefore, spectrum management solutions should have the features to improve spectrum access in both temporal and spatial manner. Cognitive Radio (CR) with the Dynamic Spectrum Access (DSA) is considered to be the key technology in this research in order to increase the spectrum efficiency. This is an effective solution to allow a group of Secondary Users (SUs) to share the radio spectrum initially allocated to the Primary User (PUs) at no interference. The core aim of this thesis is to develop new cognitive LTE-femtocell systems that offer a 4G vision, to facilitate the radio network management in order to increase the network capacity and further improve spectrum access probabilities. In this thesis, a new spectrum management model for cognitive radio networks is considered to enable a seamless integration of multi-access technology with existing networks. This involves the design of efficient resource allocation algorithms that are able to respond to the rapid changes in the dynamic wireless environment and primary users activities. Throughout this thesis a variety of network upgraded functions are developed using application simulation scenarios. Therefore, the proposed algorithms, mechanisms, methods, and system models are not restricted in the considered networks, but rather have a wider applicability to be used in other technologies. This thesis mainly investigates three aspects of research issues relating to the efficient management of cognitive networks: First, novel spectrum resource management modules are proposed to maximise the spectrum access by rapidly detecting the available transmission opportunities. Secondly, a developed pilot power controlling algorithm is introduced to minimise the power consumption by considering mobile position and application requirements. Also, there is investigation on the impact of deploying different numbers of femtocell base stations in LTE domain to identify the optimum cell size for future networks. Finally, a novel call admission control mechanism for mobility management is proposed to support seamless handover between LTE and femtocell domains. This is performed by assigning high speed mobile users to the LTE system to avoid unnecessary handovers. The proposed solutions were examined by simulation and numerical analysis to show the strength of cognitive femtocell deployment for the required applications. The results show that the new system design based on cognitive radio configuration enable an efficient resource management in terms of spectrum allocation, adaptive pilot power control, and mobile handover. The proposed framework and algorithms offer a novel spectrum management for self organised LTE-femtocell architecture. Eventually, this research shows that certain architectures fulfilling spectrum management requirements are implementable in practice and display good performance in dynamic wireless environments which recommends the consideration of CR systems in LTE and femtocell networks.
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Vemuri, Krishna Karthik. "A Multi-User Coordination Scheme for LTE Indoor Positioning System." University of Cincinnati / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1601993204475943.
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Pandey, Preetanshu. "Application evaluation of a prototype backscatter imaging LDV system (BILS)." Morgantown, W. Va. : [West Virginia University Libraries], 2002. http://etd.wvu.edu/templates/showETD.cfm?recnum=2660.
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Thesis (M.S.)--West Virginia University, 2002.Title from document title page. Document formatted into pages; contains xi, 100 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 83-86).
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Sparks, Christopher A. "Investigations of neuronal network responses to electrical stimulation in murine spinal cultures." Thesis, University of North Texas, 2001. https://digital.library.unt.edu/ark:/67531/metadc3027/.
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Spontaneous activity in neuronal networks in vitro is common and has been well documented. However, alteration of spontaneous activity in such networks via conditioning electrical stimulation has received much less experimental attention. Two different patterns of electrical stimulation were used to enhance or depress the level of spontaneous activity in spinal cord cultures. High-frequency stimulation (HFS), a method routinely shown to increase the efficacy of synaptic transmission, was employed to augment spontaneous activity. Low-frequency stimulation (LFS), the technique often applied to depress synaptic efficacy, was employed to decrease spontaneous activity. In addition, LFS was used to reverse the effect of HFS on spontaneous activity. Likewise, HFS was applied to counter the effect of LFS. Because these networks were grown on multi-microelectrode plates (MMEPs), this allowed the simultaneous stimulation of any combination of the 64 electrodes in the array. Thus, the possible differences in response to single versus multi-electrode stimulation were also addressed. Finally, test-pulses were delivered before and after the conditioning stimulation on the same stimulation electrode(s) in order to assess the change in mean evoked action potentials (MEAPs). Dissociated spinal tissue from embryonic mice was allowed to mature into self-organized networks that exhibited spontaneous bursting activity after two weeks of incubation. Spontaneous activity was monitored from up to 14 recording channels simultaneously. Although uniform responses to stimulation across all recording electrodes were rarely observed, a large majority of the recording channels had similar responses. Spontaneous activity was increased in 52% of 89 HFS trials, whereas activity was decreased in 35% of 75 LFS trials. The duration of most of these increases was less than 5 minutes. When there were substantial and long-term (> 15 min) changes in spontaneous activity, the opposing stimulation pattern successfully reversed the effect of the previous stimulation. The percent change in MEAPs following conditioning stimulation suggested that synaptic modification had taken place in 75% of all test-pulse stimulation trials.
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Dautbegovic, Dino. "Convex Optimization Methods for System Identification." Thesis, Linnéuniversitetet, Institutionen för fysik och elektroteknik (IFE), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-34808.
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The extensive use of a least-squares problem formulation in many fields is partly motivated by the existence of an analytic solution formula which makes the theory comprehensible and readily applicable, but also easily embedded in computer-aided design or analysis tools. While the mathematics behind convex optimization has been studied for about a century, several recent researches have stimulated a new interest in the topic. Convex optimization, being a special class of mathematical optimization problems, can be considered as generalization of both least-squares and linear programming. As in the case of a linear programming problem there is in general no simple analytical formula that can be used to find the solution of a convex optimization problem. There exists however efficient methods or software implementations for solving a large class of convex problems. The challenge and the state of the art in using convex optimization comes from the difficulty in recognizing and formulating the problem. The main goal of this thesis is to investigate the potential advantages and benefits of convex optimization techniques in the field of system identification. The primary work focuses on parametric discrete-time system identification models in which we assume or choose a specific model structure and try to estimate the model parameters for best fit using experimental input-output (IO) data. By developing a working knowledge of convex optimization and treating the system identification problem as a convex optimization problem will allow us to reduce the uncertainties in the parameter estimation. This is achieved by reecting prior knowledge about the system in terms of constraint functions in the least-squares formulation.
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Hanzaz, Zakaria [Verfasser]. "Optimization of the Link-to-System Interface for the System Level Evaluation based on the LTE System / Zakaria Hanzaz." München : Verlag Dr. Hut, 2017. http://d-nb.info/1135596824/34.
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Rai, Anurag. "Analysis and Design Tools for Structured Feedback Systems." BYU ScholarsArchive, 2012. https://scholarsarchive.byu.edu/etd/3270.
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As we begin to analyze and construct extremely complex systems, a theory for understanding and designing the underlying architecture becomes very important. To move in the direction of a precise theory of architecture, this thesis will provide some concrete tools to analyze and design complex systems with a given network structure. The first main result of this thesis analyzes the vulnerability of a system and shows that a system's vulnerability depends on its network structure. We will consider destabilization attacks acting on a single link in a system's logical interconnection structure. The concept of a vulnerable link is characterized and necessary and sufficient conditions for identifying these links are provided. The vulnerability of various system architectures are then characterized by the vulnerability of their weakest link, and it is shown that every transfer function has a completely secure architecture with no vulnerable links. The second part of this thesis focuses on synthesizing controllers with a specified network structure. It presents a new approach to distributed controller design that exploits the dynamical structure function representation of linear time invariant systems to characterize the structure of a system. The design technique sequentially constructs each link in an arbitrary controller signal structure, and the main theorem proves that either the resulting controller is stabilizing or that no controller with the desired structure can stabilize the system.
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Škúci, Michal. "Aktivní tlumení hlavy obráběcího stroje." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2013. http://www.nusl.cz/ntk/nusl-230467.
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The master’s thesis deals with building mechatronics model of machine tool head delivered by company TOSHULIN,a.s. for purpose of damping vibration. Mechanical part of the model is based on modeling of system of flexible bodies. Components are modeled in FEM program ANSYS and subsequently reduced using Craig-Bampton method. The system of flexible bo-dies is created in MBS program ADAMS. Model is linearized and subsequently reduced. As a element of active damping is used linearized model of magnetic bearing. For control is desig-ned PID controller. The comparison of damped and undamped model is conducted in the end.
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Xu, Ziwei. "LTL Motion Planning with Collision Avoidance for A Team of Quadrotors." Thesis, KTH, Skolan för elektro- och systemteknik (EES), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-196904.
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Linear Temporal Logic (LTL), as one of the temporal logic, can generate a fully automated correct-by-design controller synthesis approach for single or multiple autonomous vehicles, under much more complex missions than the traditional point-to-point navigation.In this master thesis, a framework which combines model- checking-based robot motion planning with action planning is proposed based on LTL for-mulas. The specifications implicitly require both sequential regions for multi-agent to visit and the desired actions to perform at these regions while avoid-ing collision with each other and fixed obstacles. The high level motion and task planning and low level navigation function based collision avoidance controller are verified by nontrivial simulation and implementation on real quadcopter in Smart Mobility Lab.
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Dragan, Rastovac. "Analiza energetske efikasnosti isporuke multimedijalnih servisa u mobilnim ćelijskim sistemima četvrte generacije (LTE/LTE-A)." Phd thesis, Univerzitet u Novom Sadu, Fakultet tehničkih nauka u Novom Sadu, 2016. http://www.cris.uns.ac.rs/record.jsf?recordId=101087&source=NDLTD&language=en.
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U ovoj disertaciji razvijeni su analitički alati za izračunavanje protoka servisa, propusnog opsega i uštede energije zahtevanim u različitim eMBMS LTE/LTE-A servisnim strukturama. Takođe, mi smo analizirali protok podataka i optimalnu dodelu parametara za prenos na fizičkom sloju za eMBMS baziran video servis u 2-klasnoj heterogenoj mreži primenom stohastičke geometrije.In this dissertation we develop simple analytical tools for evaluation of average service data rates, bandwidth and energy consumption requirements in dierent eMBMS LTE/LTE-A service congurations. Also, we consider a simple approach to estimate achievable rates and optimally assign the physical layer transmission parameters for eMBMS based video service in the two-tier heterogeneous cellular systems.
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DURBHA, SRIRAM. "A METHODOLOGY FOR ANALYZING HARDWARE ACCELERATED CONTINUOUS-TIME METHODS FOR MIXED SIGNAL SIMULATION." University of Cincinnati / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1091060658.
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Kogiantis, Achilles, Kiran Rege, and Anthony A. Triolo. "LTE SYSTEM ARCHITECTURE FOR COVERAGE AND DOPPLER REDUCTION IN RANGE TELEMETRY." International Foundation for Telemetering, 2017. http://hdl.handle.net/10150/626975.
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A novel approach employing 4G LTE Cellular Technology for Test Range Telemetry is presented. Providing aeronautical mobile telemetry using commercial off the shelf (COTS) cellular equipment poses many challenges, including: Three-dimensional (3D) coverage, need for uninterrupted high data throughputs, and very high Doppler speeds of the Test Articles (TA). Each of these requirements is difficult to meet with a standard cellular approach. We present a novel architecture that provides 3D coverage over the span of a test range, allowing the TA to establish a radio link with base stations that have a manageable Doppler due to the reduced projected TA speed on the radio link line. Preliminary results illustrate that a variety of flight plans can be accommodated with commercial LTE technology by employing LTE’s mobility mechanisms and adding centralized control. The resulting network architecture and Radio Access Network topology allow very high throughputs to be delivered throughout the test range with a judicious placement of base stations.
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Kalalas, Charalampos. "Enabling LTE for Control System Applications in a Smart Grid Context." Thesis, KTH, Reglerteknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-150344.
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The next generation electric power system, known as Smart Grid, is expected to alleviate the energy shortage problem by exploiting renewable energy resources. The Smart Grid communication network, with its diverse structure, constitutes an indispensable component in the new power system. In terms of power industry standards, the International Electrotechnical Commission (IEC) 61850 framework is of particular note. Originally defined to cover the stringent requirements for automation within the substation, IEC 61850 is proving to be a versatile standard that can also be applied to the medium- and low-voltage networks while facilitating control applications. Long Term Evolution (LTE) appears as a remarkable candidate for supporting remote automation tasks in the electricity grid, offering low latency, high throughput and quality of service differentiation in a single radio access technology. In the context of the thesis, a performance evaluation of the integration of LTE technology with IEC 61850 communication services is carried out. A characterization of the network architecture and the performance requirements for intelligent power system management is performed and an analytical model for the scheduling framework is proposed. Emphasis is given on the development of optimal prioritization schemes and techniques in order to ensure control data scheduling in situations when LTE background traffic coexists in the network. In addition, realistic communication scenarios specifically designed to emulate real network operations are considered and extensive simulations are performed with the use of Ericsson’s radio system simulator platform. The results have demonstrated that LTE networks successfully meet the performance requirements for wide-area automation tasks within a Smart Grid context. Given the size of the LTE ecosystem, such an evolution constitutes an attractive path for future wireless communication.
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"GNSS-LTE/LTE-A interference mitigation : the adjacent channel rejection ratio approach." Thesis, 2015. http://hdl.handle.net/10210/14525.
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M.Ing.The increase of interest in the development of radio communications, both terrestrial and satellite is reaching far and beyond the most optimistic expectations. There has been an accelerated emergence of newer technologies, all claiming highly coveted radio frequency spectrum resources. With the push for the development of location based services, utilizing satellite com- communications for military purposes and later for civilian use; there has been a parallel development in terrestrial communications technology making it possible to implement cost efficient reliable user systems for voice and data services ...
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Yu, Hong-Kai, and 游宏凱. "LEV suspension system design and development." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/00507224970244250818.
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碩士國立屏東科技大學
車輛工程系所
101
In this study, the vehicle suspension systems design and analysis procedure have been proposed for the Light-weight Electric Vehicles. The contents including the static load analysis, kinematic analysis, mechanical motion and force analysis, component stresses analysis, and vehicle dynamics simulation and test. In the static load analysis, different axle load conditions have been calculated. The loads can be important boundary conditions for the analysis of each component, which can be used to make sure the strength in different force conditions. In the analysis of mechanism, the changes of the suspension parameters improved the performance according to the design procedure. In the vehicle dynamic test and simulations, the kinematic model was compared with the real road test. And different road conditions are came in to find out the critical parameter for avoid the dangerous driving and can be used as judgment parameters for active warring systems.
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Wang, Chuan, and 王銓. "MIMO Precoder Selection for 3GPP-LTE/LTE-A Systems." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/79141216008839178147.
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碩士國立中央大學
電機工程學系
101
Precoder Selection Under MIMO Detection for 3GPP-LTE/LTE-A Systems Abstract Precoding by using a finite-set codebook at transmitters is an effective approach to improve the performance of multiple-input multiple-output (MIMO) systems with reduced feedback overhead. K-Best sphere decoders are popular for high-throughput spatially-multiplexed MIMO signal detection at receivers. In this paper, we propose a precoding-matrix-index (PMI) selection criterion suitable for K-best MIMO detectors by minimizing the trace of the upper triangular matrix after QR decomposition (QRD). To further improve the system performance, fully-sorted QRD, per-layer sorted QRD and partially-sorted QRD are also proposed to be incorporated in the minimum-trace PMI selection criterion. Simulation results based on the MIMO codebooks of 3GPP-LTE/LTE-A systems show the improvements of the proposed scheme compared to the non-precoding MIMO schemes and the precoding schemes using the conventional PMI selection criterions. Considering the fading channel in time/frequency domain of LTE system, we propose a group solution, which not only provide much lower computation, but also avoid more degradating. As to the hardware implementation, we use a scalable design of high throughput 8×8 Sorted QRD. It can compute three sets of 4×4 Sorted QRD simultaneously. Various numbers of sorting layers are supported for our proposed precoding criterion.
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Zheng, Qian. "Saturation control of LTI systems." 2005. http://www.lib.ncsu.edu/theses/available/etd-09212005-114354/unrestricted/etd.pdf.
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邱中玓. "Internet Traffic Identification Mechanism in LTE System." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/04318941884578497728.
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碩士國立交通大學
電信工程研究所
101
Discontinuous reception (DRX) Cycle mechanism is adopted in Long Term Evolution (LTE) system to minimize the power consumption of user equipment (UE). DRX Cycle must be set to suit the Internet traffic to obtain the optimum performance for power saving. If there is no packet to transmit/receive, UE will turn off the transmitter/receiver based on DRX Cycle to reduce the power of UE. In this thesis, we proposed a mechanism to identify Internet traffic in LTE system. First, we adopted Support Vector Machine (SVM) algorithm for traffic classification. Then, we modeled Background traffic with a simplified bursty packet data distribution and defined a value to detect the use of Instant Message traffic. Finally, we proposed a method of calculation to recognize the characteristics of Background traffic and Instant Message traffic. Simulation results show the numerical parameters to represent on-line traffic. With these constantly updating parameters from the packets we captured, we can recognize the situation and characteristics of the traffic we are using. It provides a guideline for DRX researchers.
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Tsao, Bo-Jhong, and 曹伯仲. "Cell Search for 3GPP LTE Communication System." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/50232537438347064689.
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碩士國立中央大學
通訊工程研究所
98
LTE（long term evolution）wireless communication downlink system uses OFDMA. This system uses the primary synchronization signal (P-SCH) and the secondary synchronization signal(S-SCH) for synchronization and cell identities solving problems. However, it is well known that OFDM systems are sensitive to time and frequency synchronization error. Hence we require accurate synchronization techniques. Furthermore, user equipment (UE) operates in a cellular system, and there are 504 cell-ID in LTE, it needs to establish connection as fast as possible with the best serving base station, i.e. to identify the operating sector and cell. The proposed cell search procedure in this paper contains three steps: The first step, using the delay auto-correlation to find frame timing and the primary synchronization signal, and then use this sequence to start estimate the symbol timing and fractional frequency. And in the estimation we use the average method to improve the accuracy of fractional frequency. The second step, we use method of the phase difference between each signal with synchronization to confirm sector and the integer frequency. And the outcome shows that it can effectively withstand the error of channel effect and symbol timing. The third step, confirm cell-ID. The proposed algorithm confirms the sector and cell ID by phase difference, it can resist the channel effect, and it is more stabilize than matched filter.
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Liu, Hsiun-Fu, and 劉訓甫. "Relay Assignment Strategy in LTE-Advanced System." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/14127471096161345574.
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碩士國立臺灣大學
電機工程學研究所
99
There were many works on the research of relay assignment issue. Relay network, in the form of keeping each its own antennas and having a node exploit a relay node’s antennas, is shown to be a promising approach to enhance spatial diversity. Moreover, improving the spatial diversity of transmission could achieve the main purpose of increasing performance in data transmission. In this work, we pay our attention to the multiple-users-multiple-relays relay assignment on LTE-Advanced (4G) , the future communication technology, because relay transmission is an important concept in LTE-Advanced system. We will proposed a strategy called RIMM for assignment of multiple relay nodes (RN) to multiple users (UE): We want to maximize UEsawareness of performance improvement overall system after introducing the relay nodes (RN). Instead of maximizing the aggregate performance, we want to take our main purpose on maximizing the relative improvement of users (UE) overall system, that is a ratio of performance improvement to the corresponding original performance value and achieve the max-min feature simultaneously. By that relay strategy, it will take advantage of increasing the spatial diversity and the performance of transmission to achieve the perspective of improving the inferior users’ (UE) transmission performance. Then we will transform the relay assignment problem with this relay strategy into bipartite matching problem and introduce the Hungarian algorithm to get the optimal solutions.
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Li, Chi-Ming, and 李啓銘. "Location Recommendation Algorithm in LTE Communication System." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/68s392.
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碩士國立臺灣師範大學
電機工程學系
105
In this thesis, we propose a user location recommendation algorithm in the Long Term Evolution (LTE) Downlink communication. The proposed location recommendation algorithm is further combined with Modified Largest Weighted Delay First (MLWDF) to improve system performances such as throughput, packet delay and packet loss rate. From the simulation results, we find that the Quality of Services (QoS) including throughput and packet loss rates of Voice over IP (VoIP) and video in LTE Downlink communications can be improved by using the proposed user recommendation algorithm. . Keywords— Long Term Evolution (LTE), Location Recommendation, Resource Allocation, QoS (Quality of Service).
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Lin, Chia-wei, and 林家葳. "Study on Channel Estimation and System Implement for LTE MIMO System." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/90740301663411257166.
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碩士國立中山大學
通訊工程研究所
104
Long term evolution (LTE) has become the fourth generation of mobile phone mobile communication technology standards (4G). Orthogonal frequency division multiplexing and MIMO technology has been used in the downlink channel because this technique can serve the huge demand due to the explosive growth of the large number of data sent by users. The system studied in this thesis is based on LTE. To perform the channel estimation, the transmitters send a pre-defined signal called pilot signal and then the channel can be estimated based on the pilot signal. Based on the estimated channel, the data symbols distorted by the propagation channel can be recovered by the channel information. This thesis aims to examine the LTE downlink channel estimation methods including the least squares and the minimum mean square error approaches, and then we compare the performance by mean square error. In addition, signal-to-noise ratio of the system can be estimated precisely based on the estimated channel information. The results of this thesis are implemented in the LTE multi-antenna measurement software radio platform.
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Yu, Sheng-Wen, and 余聖文. "Implementation of LTE RF receiver systems." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/39204177357185317374.
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碩士國立勤益科技大學
電子工程系
102
The trend in wireless technology prevails globally, and new technologies are developed and advanced rapidly. Wireless communication systems have evolved from the use of analog signals to digital signals, and fixed equipment has been developed into portable equipment for users. Thus, people are benefiting from achievements in the surge of wireless equipment development. Smart phones and tablet computers have promoted the use of mobile Internet. According to the development of the global mobile communications market, this study was divided into two sections. In the first section, the evolution of 1G to 4G wireless communications was sequentially examined. Numerous industry analyses and data comparisons were used to explore the 4G wireless communications market and industry structure both domestically (in Taiwan) and globally. Because long-term evolution (LTE) is a mainstream standard of 4G wireless communications, in the second section, radio frequency (RF) front-end circuits that can be applied in LTE systems were proposed. The direct-conversion receiver framework was employed. LT5500 chips developed by Linear Technology were selected for this study. Regarding the circuit design and layout, electromagnetic compatibility (EMC) analysis was conducted. Under 1.35 V operating voltage, the frequency bands of the circuit were recorded as 1.5 G and 2.5 G. The S parameters for the high and low gain modes of low-noise amplifiers (LNAs) and for frequency mixers at 2.5 G RF and 2.22 G local oscillator (LO) frequency bands with 280 MHz intermediate frequency (IF) output were also recorded.
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Heidari, Roshanak. "Packet scheduling algorithms in LTE systems." Thesis, 2017. http://hdl.handle.net/10453/123167.
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University of Technology Sydney. Faculty of Engineering and Information Technology.There has been a huge increase in demand towards improving the Quality of Service (QoS) of wireless services. Long Term Evolution (LTE) is a development of the Third-Generation Partnership Project (3GPP) with the aim to meet the needs of International Telecommunication Union (ITU). Some of its aspects are highlighted as follows: increase in data rate, scalable bandwidth, reduced latency and increase in coverage and capacity that result in better quality of service in communication. LTE employs Orthogonal Frequency Division Multiple Access (OFDMA) to simultaneously deliver multimedia services at a high speed rate. Packet switching is used by LTE to support different media services. To meet the QoS requirements for LTE networks, packet scheduling has been employed. Packet scheduling decides when and how different packets are delivered to the receiver. It is responsible for smart user packet selection to allocate radio resources appropriately. Therefore, packet scheduling should be cleverly designed to achieve QoS that is similar to fixed line services. eNodeB is a node in LTE network which is responsible for radio resource management that involves packet scheduling. There are two main categories of application in multimedia services: RT (Real Time) and NRT (None Real Time) services. RT services are either delay sensitive (e.g. voice over IP), loss sensitive (e.g. Buffered Video) or both (delay &loss sensitive) for example video conferencing. Best effort users are an example of NRT services that do not have exact requisites and have been allocated to spare resources. Reaching higher throughput has sometimes resulted in unfair allocation to users who are located far from the base station or users who suffer from bad channel conditions. Therefore, a sufficient trade-off between throughput and fairness is essential. The scarce bandwidth, fading radio channels and the QoS requirement of the users, makes resource allocation a demanding issue. Different scheduling approaches have been suggested for different service demands described briefly throughout the thesis. Initially, a comprehensive literature review of existing work on the packet scheduling topic has been accomplished in this thesis to realize the characteristics of packet scheduling and the resource allocation for the wireless network. Many packet scheduling algorithms developed to provide satisfactory QoS for multimedia services in downlink LTE systems. Several algorithms considered in this thesis include time and frequency domain algorithms and their way of approach has been investigated. The next objective of this thesis is to improve the performance of packet scheduling in LTE downlink systems. A new packet scheduling algorithm has been introduced in this thesis. A study on VoLTE (Voice over LTE), video streaming and best effort traffic under three different scheduling algorithms has been conducted. Heterogeneous traffic based on precise modelling of packets has been used in the simulation. The main resource allocation and assignment technique used in this work namely Dynamic Subcarrier Allocation scheme is shown to provide a solution to solve the cross layer optimisation problem. It depends on Channel Quality Information (CQI) and has been broadly investigated for single carrier and multicarrier wireless networks. The problem is based on the maximisation of average utility functions. Different scheduling algorithms in this method consider to be utility functions. The throughput, fairness and Packet Loss Ratio have been considered as the requirements for examining the performance of algorithms. Simulation results show that the proposed algorithm significantly increases the performance of streaming and best effort users in terms of PLR and throughput. Fairness has also been improved with less computational complexity compared to previous algorithms that have been introduced in this thesis.
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Lee, Tsao-Hsuan, and 李肇軒. "High-Throughput Turbo Decoder Design with New Interconnection Network for LTE/LTE-A System." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/87123179754476132422.
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碩士國立中央大學
電機工程學系
101
In this paper, we design and implement a high-throughput turbo decoder for the 3rd Generation Partnership Project (3GPP) Long Term Evolution-Advanced (LTE-advanced) system. To support the high data rate, we adopts eight radix-4 parallel soft-in/soft-output MAP decoders. We adopt MAP decoding with sliding window mechanism to decrease decoding time. And we also use the warm-up scheme to compensate the performance loss. Besides, The properties of quadratic permutation polynomial (QPP) interleaver are exploited to reduce the complexity of the switch network between memory and MAP decoder. Four techniques are used to improve the hardware design. First, the in-place algorithm is adopted to decrease the size of α-memory in MAP decoder , and hence the overall area can be reduced. Next, the processing periods of the last window in the first half iteration and the first window in the second half iterations are scheduled to be overlapped, Consequently, the decoding time is reduced and the throughput of the turbo decoder can be enhanced. The interconnection network is designed elaborately. A new interconnection network is proposed with a simple rotator and control logic. Using simple conditional judgement with extra multiplexers to exchange the address and memory data, we can support parallel processing of the turbo decoding. In addition, We achieve non-conflict memory access under high parallel and high radix hardware design for 188 modes . From synthesis result, this work can operate at 406 MHz to offer decoding data rate up to 511 Mbps in 90nm CMOS technology.