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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
121

Improving Channel Estimation and Tracking Performance in Distributed MIMO Communication Systems

David, Radu Alin 29 April 2015 (has links)
This dissertation develops and analyzes several techniques for improving channel estimation and tracking performance in distributed multi-input multi-output (D-MIMO) wireless communication systems. D-MIMO communication systems have been studied for the last decade and are known to offer the benefits of antenna arrays, e.g., improved range and data rates, to systems of single-antenna devices. D-MIMO communication systems are considered a promising technology for future wireless standards including advanced cellular communication systems. This dissertation considers problems related to channel estimation and tracking in D-MIMO communication systems and is focused on three related topics: (i) characterizing oscillator stability for nodes in D-MIMO systems, (ii) the development of an optimal unified tracking framework and a performance comparison to previously considered sub-optimal tracking approaches, and (iii) incorporating independent kinematics into dynamic channel models and using accelerometers to improve channel tracking performance. A key challenge of D-MIMO systems is estimating and tracking the time-varying channels present between each pair of nodes in the system. Even if the propagation channel between a pair of nodes is time-invariant, the independent local oscillators in each node cause the carrier phases and frequencies and the effective channels between the nodes to have random time-varying phase offsets. The first part of this dissertation considers the problem of characterizing the stability parameters of the oscillators used as references for the transmitted waveforms. Having good estimates of these parameters is critical to facilitate optimal tracking of the phase and frequency offsets. We develop a new method for estimating these oscillator stability parameters based on Allan deviation measurements and compare this method to several previously developed parameter estimation techniques based on innovation covariance whitening. The Allan deviation method is validated with both simulations and experimental data from low-precision and high-precision oscillators. The second part of this dissertation considers a D-MIMO scenario with $N_t$ transmitters and $N_r$ receivers. While there are $N_t imes N_r$ node-to-node pairwise channels in such a system, there are only $N_t + N_r$ independent oscillators. We develop a new unified tracking model where one Kalman filter jointly tracks all of the pairwise channels and compare the performance of unified tracking to previously developed suboptimal local tracking approaches where the channels are not jointly tracked. Numerical results show that unified tracking tends to provide similar beamforming performance to local tracking but can provide significantly better nullforming performance in some scenarios. The third part of this dissertation considers a scenario where the transmit nodes in a D-MIMO system have independent kinematics. In general, this makes the channel tracking problem more difficult since the independent kinematics make the D-MIMO channels less predictable. We develop dynamics models which incorporate the effects of acceleration on oscillator frequency and displacement on propagation time. The tracking performance of a system with conventional feedback is compared to a system with conventional feedback and local accelerometer measurements. Numerical results show that the tracking performance is significantly improved with local accelerometer measurements.
122

Mitigating the Effects of Ionospheric Scintillation on GPS Carrier Recovery

Olivarez, Nathan 23 April 2013 (has links)
Ionospheric scintillation is a phenomenon caused by varying concentrations of charged particles in the upper atmosphere that induces deep fades and rapid phase rotations in satellite signals, including GPS. During periods of scintillation, carrier tracking loops often lose lock on the signal because the rapid phase rotations generate cycle slips in the PLL. One solution to mitigating this problem is by employing decision-directed carrier recovery algorithms that achieve data wipe-off using differential bit detection techniques. Other techniques involve PLLs with variable bandwidth and variable integration times. Since nearly 60% of the GPS signal repeats between frames, this thesis explores PLLs utilizing variable integration times and decision-directed algorithms that exploit the repeating data as a training sequence to aid in phase error estimation. Experiments conducted using a GPS signal generator, software radio, and MATLAB scintillation testbed compare the bit error rate of each of the receiver models. Training-based methods utilizing variable integration times show significant reductions in the likelihood of total loss of lock.
123

Levantamento arqueológico na reserva de desenvolvimento sustentável (RDS) Amanã: Estado do Amazonas / Archaeological Survey at SDR-Amanã Amazonas State

Costa, Bernardo Lacale Silva da 05 December 2012 (has links)
Este trabalho apresenta os resultados preliminares de levantamento arqueológico realizado na RDS Amanã, Estado do Amazonas. Situada na região do médio curso do rio Solimões e baixo Japurá, a RDS Amanã está na fase de preparo do seu plano de gestão. A respeito do Patrimônio Arqueológico existente na reserva Amanã 32 sítios arqueológicos formados por terra preta, cerâmica e material lítico polido foram identificados em etapas de levantamento realizadas entre 2006 e 2008. Levando em consideração o tamanho, densidade e variabilidade dos vestígios arqueológicos, assim como, a intensidade dos processos pós-deposicionais os sítios Boa Esperança e Bom Jesus do Baré foram escolhidos para realização de mapeamentos e escavação. O objetivo principal desse mestrado é apresentar o contexto arqueológico da reserva Amanã a partir de uma perspectiva comparativa com pesquisas arqueológicas que ocorrem em outros locais da Amazônia. Mais especificamente com a cronologia estabelecida para as ocupações ceramistas na Amazônia Central e áreas adjacentes, como Baixo Amazonas e médio Rio Caquetá/Japurá. A partir de dados relativos ao tamanho, composição, formato e estratigrafia dos sítios, assim como analise cerâmica e datações é formulada uma cronologia preliminar para o lago Amanã. / The main goal of this dissertation is to introduce the archaeological context of the Amanã Sustainable Development Reserve, situated near the middle course of the Amazon and the lower course of the Japurá Rivers, in the state of Amazonas; its management plan is currently under preparation. This context is then compared to the archaeology of other areas of Amazonia. Preliminary results of the archaeological survey carried out between 2006 and 2008 will be presented, during which time 32 archaeological sites were identified. These are composed of anthropogenic dark earth, pottery and ground lithics. The Boa Esperança and Bom Jesus do Baré archaeological sites were selected for mapping and excavation due to their size, density and the variability of archaeological material they contain. An initial chronology for the Amanã Lake is put forward, based on data related to site size, composition, form and stratigraphy. This is then contrasted to ceramicist occupations identified in the Central Amazon and adjacent areas (the Lower Amazon and middle Caquetá/Japurá). Such a comparative approach is employed as a tool to allow the insertion of the Amanã Lake in the wider scenario, in this way allowing for a contribution to debates and discussions that are important to Amazonian Archaeology, such as the origin and dispersal of ceramic traditions. The data will further provide information to be utilized with local inhabitants for the future development of research, public archaeology and the reserve\'s management activities.
124

Jitter-Tolerance and Blocker-Tolerance of Delta-Sigma Analog-to-Digital Converters for Saw-Less Multi-Standard Receivers

Ahmed, Ramy 1981- 14 March 2013 (has links)
The quest for multi-standard and software-defined radio (SDR) receivers calls for high flexibility in the receiver building-blocks so that to accommodate several wireless services using a single receiver chain in mobile handsets. A potential approach to achieve flexibility in the receiver is to move the analog-to-digital converter (ADC) closer to the antenna so that to exploit the enormous advances in digital signal processing, in terms of technology scaling, speed, and programmability. In this context, continuous-time (CT) delta-sigma (ΔƩ) ADCs show up as an attractive option. CT ΔƩ ADCs have gained significant attention in wideband receivers, owing to their amenability to operate at a higher-speed with lower power consumption compared to discrete-time (DT) implementations, inherent anti-aliasing, and robustness to sampling errors in the loop quantizer. However, as the ADC moves closer to the antenna, several blockers and interferers are present at the ADC input. Thus, it is important to investigate the sensitivities of CT ΔƩ ADCs to out-of-band (OOB) blockers and find the design considerations and solutions needed to maintain the performance of CT ΔƩ modulators in presence of OOB blockers. Also, CT ΔƩ modulators suffer from a critical limitation due to their high sensitivity to the clock-jitter in the feedback digital-to-analog converter (DAC) sampling-clock. In this context, the research work presented in this thesis is divided into two main parts. First, the effects of OOB blockers on the performance of CT ΔƩ modulators are investigated and analyzed through a detailed study. A potential solution is proposed to alleviate the effect of noise folding caused by intermodulation between OOB blockers and shaped quantization noise at the modulator input stage through current-mode integration. Second, a novel DAC solution that achieves tolerance to pulse-width jitter by spectrally shaping the jitter induced errors is presented. This jitter-tolerant DAC doesn’t add extra requirements on the slew-rate or the gain-bandwidth product of the loop filter amplifiers. The proposed DAC was implemented in a 90nm CMOS prototype chip and provided a measured attenuation for in-band jitter induced noise by 26.7dB and in-band DAC noise by 5dB, compared to conventional current-steering DAC, and consumes 719µwatts from 1.3V supply.
125

Implementation of a Software-Defined Radio Transceiver on High-Speed Digitizer/Generator SDR14

Björklund, Daniel January 2012 (has links)
This thesis describes the specification, design and implementation of a software-defined radio system on a two-channel 14-bit digitizer/generator. The multi-stage interpolations and decimations which are required to operate two analog-to-digital converters at 800 megasamples per second (MSps) and two digital-to-analog converters at 1600 MSps from a 25 MSps software-side interface, were designed and implemented. Quadrature processing was used throughout the system, and a combination of fine-tunable low-rate mixers and coarse high-rate mixers were implemented to allow frequency translation across the entire first Nyquist band of the converters. Various reconstruction filter designs for the transmitter side were investigated and a cheap implementation was done through the use of programmable base-band filters and polynomial approximation.
126

Digital Radio Implementation for NASA S-Band Space Network Transceiver

Berhanu, Samuel, Neupane, Kamal 10 1900 (has links)
The system diagrams for the digital radio compatible with NASA's S-Band Space Network operating from 2025.8 - 2117.9 MHz (forward link) to 2200 - 2300 MHz (return link) are presented. The digital radio implementation includes binary phase shift keying (BPSK), quadrature phase shift keying (QPSK) and staggered quadrature phase shift keying (SQPSK). We have derived the system requirements for these modulation schemes from the Space Network User Guide (SNUG) and thereafter, derived system diagrams for the communication links. The designed system diagrams for the transceiver were implemented using Simulink models and USRP2 platform.
127

Network on chip based multiprocessor system on chip for wireless software defined cognitive radio

Taj, Muhammad Imran 12 September 2011 (has links) (PDF)
Software Defined Radio (SDR) and Cognitive Radio (CR) are entering mainstream. These high performance and high adaptability requiring devices with agile frequency operations hold promise to :1. address the inconsistency between hardware and software advancements, 2. real time mode switching from one radio configuration to another and3. efficient spectrum management in under-utilized spectrum bands. Framed within this statement, in this thesis we have implemented a SDR waveform on 16 Processing Element (PE) Network on chip (NoC) based general purpose Multiprocessors System on chip (MPSoC), with access to four external DDR2 memory banks, which is implemented on a single chip Xilinx Virtex-4 FPGA. We shifted short term development of a waveform into software domain by designing an efficient parallelization and synchronization strategy for each waveform component, individually. We enhance our designed waveform functionality by proposing and implementing three Artificial Neural Networks Schemes : Self Organizing Maps, Linear Vector Quantization and Multi-Layer Perceptrons as effective techniques for reconfiguring CR Transceiver after recognizing the specific standard based on input parameters, pertaining to different layers, extracted from the signal. Our proposed adaptive solution switches to appropriate Artificial Neural Network, based on the features of input signal sensed. We designed an efficient synchronization and parallelization strategy to implement the Artificial Neural Networks based CR Transceiver Algorithms on the aforementioned MPSoC chip. The speed up we obtained for our SDR waveform and CR Transceiver algorithms demonstrated that the general purpose MPSoC devices are the most efficient answer to the acquisition challenge for major organizations that invest or plan to invest in SDR and CR based devices, thereby allowing us to avoid expensive hardware accelerators. We address the case of a complex signal composed of many modulated carriers by dividing the PEs in individual groups, thus received signal with more than one Standard is processed efficiently. We add further functionality in our designed Multi-standard CR Transceiver possessing SDR Waveform by proposing a new approach for radio spectrum management, perhaps the most important aspect of CR. We make our designed waveform Spectrum efficient by modelling the primary user signal Radio Frequency features as a multivariate time series, which is then given as input to Elman Recurrent Neural Network that predicts the evolution of Radio Frequency Time Series to decide if the secondary user can exploit the Spectrum band. We exploit the inherent cyclostationary in primary signals for Non-linear Autoregressive Exogenous Time Series Modeling of Radio Frequency features, as predicting one RF feature needs the previous knowledge of other relevant RF features. We observe a similar trend between predicted and actual values. Ensemble, our designed Spectrum Efficient SDR waveform with a Universal Multi-standard Transceiver answers the SDR and CR performance requirements under resource constraints by efficient algorithm design and implementation using lateral thinking that seeks a greater cross-domain interaction
128

Impacto de condicionantes hidrológicas na definição de traçados rodoviários : aplicação na rodovia TO-247

Garcia, Lúcia Leiko Tacaoca Muraishi January 2011 (has links)
A contribuição desta pesquisa é dada através do dimensionamento dos impactos efetivos das rodovias, através da ampliação das áreas de influência para além das faixas lineares, acrescentando a avaliação da sensibilidade ambiental das bacias hidrográficas para a otimização do traçado de empreendimentos rodoviários. Foi produzida uma abordagem ordenada e sistemática das relações de causa e conseqüência nas bacias, integrando os impactos da rodovia TO-247, interligando as sedes municipais Lagoa do Tocantins e Mateiros. As sub-bacias da região da área do estudo foram classificadas mediante metodologia para estimativa de produção e transporte de sedimentos, em ambiente ArcGis ArcInfo, onde foi aplicado modelo derivado da Equação Universal da Perda de Solos (Universal Soil Loss Equation – USLE) adaptado de Wischmeier e Smith (1978) e da Relação de Distribuição de Sedimentos (Sediment Delivery Ratio – SDR) proposto por Ferro e Minacapilli (1995). Os resultados possibilitaram a classificação das sub-bacias conforme a porcentagem estimativa de carga de sedimentos que potencialmente viria a assorear os cursos d’água mediante a modificação do seu uso pela ocupação do solo induzida pela rodovia. Os critérios relevantes à definição do traçado da rodovia foram divididos em três: (1) aspectos ambientais, (2) aspectos construtivos e (3) aspectos socioeconômicos, tendo sido parametrizados através do uso de Sistema de Informação Geográfica com algoritmos em ambiente raster, na definição de caminhos de mínimo custo. A otimização da rota proposta sugere a adição de ganhos na orientação dos tomadores de decisão, como a inserção da rodovia TO-247 em bacias com menor nível de restrição de relação de aporte de sedimentos, redução das travessias sobre áreas protegidas, diminuição das obras de arte (bueiros e pontes) e da execução de cortes e aterros, incluindo a possibilidade de melhoria dos acessos aos pontos turísticos de interesse para o desenvolvimento regional. A incorporação de condicionantes hidrológicas através da classificação das bacias quanto a produção e transferência dos sedimentos destacou a principal novidade que foi a definição da área de influência delimitada pelos impactos ambientais de projetos rodoviários para os limites das bacias, podendo contribuir com o planejamento de estradas indutoras de desenvolvimento. / The contribution of this research is given by the design of effective impacts of highways, through the expansion of the influence areas beyond the linear tracks, adding the assessment of the environmental sensitivity of watersheds in order to optimize the layout of road projects. It was produced an orderly and systematic approach of the cause and consequence relations in the watersheds incorporating in it the TO-247 highway impacts, linking the cities of Mateiros and Lagoa do Tocantins. The watersheds in the region of the study area were classified using methodology for estimating production and transport of sediment in ArcGIS ArcInfo environment. It was applied the equation model derived from the Universal Soil Loss Equation - USLE adapted from Wischmeier and Smith (1978) and the Sediment Delivery Ratio - SDR according to what is proposed by Ferro and Minacapilli (1995). Those results allowed the classification of watersheds according to the percentage estimate of sediment load that would potentially silting up the waterways through modification of their usage by land use induced by the highway. The relevant criteria to define the highway route were divided into three: (1) environmental, (2) construction and (3) socioeconomic aspects, which have been parameterized by using Geographic Information System with algorithms in raster environment into the definition of low cost paths. The optimization of the route proposal in TO-247 suggests adding profit in orientation of decision makers, such as entering the highway in watersheds with lower levels of restriction regarding the amount of sediment, reduction of crossings on protected areas, reduction of culverts and bridges and the implementation of sections and embankments, including the possibility of improved access to interest tourist points for regional development. The incorporation of hydrological conditions through the classification of river watersheds as the production and transfer of sediments, which highlighted the main novelty, was the expansion circumscription of the influence area bounded by the environmental impacts of road projects for the limits of the watersheds, which may contribute to the planning of roads inducing development.
129

Feasibility of a Direct Sampling Dual-Frequency SDR Galileo Receiver for Civil Aviation / Faisabilité d’un récepteur Galileo SDR bi-fréquence à échantillonnage direct pour l’Aviation Civile

Blais, Antoine 25 September 2014 (has links)
Cette thèse étudie l'intérêt des architectures SDR à échantillonnage direct pour des récepteurs Galileo dans le contexte particulier de l'Aviation Civile, caractérisé notamment par une exigence de robustesse à des interférences bien spécifiées, principalement les interférences causées par les signaux DME ou CW. Le concept de Software Defined Radio traduit la migration toujours plus grande, au sein des récepteurs, des procédés de démodulation d'une technologie analogique à du traitement numérique, donc de façon logicielle. La quasi généralisation de ce choix de conception dans les architectures nouvelles nous a conduit à le considérer comme acquis dans notre travail. La méthode d'échantillonnage direct, ou Direct Sampling, quant à elle consiste à numériser les signaux le plus près possible de l'antenne, typiquement derrière le LNA et les filtres RF associés. Cette technique s'affranchit donc de toute conversion en fréquence intermédiaire, utilisant autant que possible le principe de l'échantillonnage passe-bande afin de minimiser la fréquence d'échantillonnage et en conséquence les coûts calculatoires ultérieurs. De plus cette thèse s'est proposée de pousser jusqu'au bout la simplification analogique en renonçant également à l'utilisation de l'AGC analogique qui équipe les récepteurs de conception traditionnelle. Seuls des amplificateurs à gain fixe précéderont l'ADC. Ce mémoire rend compte des travaux menés pour déterminer si ces choix peuvent s'appliquer aux récepteurs Galileo multifréquences (signaux E5a et E1) destinés à l'Aviation Civile. La structure du document reflète la démarche qui a été la notre durant cette thèse et qui a consisté à partir de l'antenne pour, d'étape en étape, aboutir au signal numérique traité par la partie SDR. Après une introduction détaillant le problème posé et le contexte dans lequel il s'inscrit, le deuxième chapitre étudie les exigences de robustesse aux interférences auquel doit se soumettre un récepteur de navigation par satellites destiné à l'Aviation Civile. Il s'agit de la base qui conditionne toute la démarche à suivre. Le troisième chapitre est consacré au calcul des fréquences d'échantillonnage. Deux architectures d'échantillonnage sont proposées. La première met en oeuvre un échantillonnage cohérent des deux bandes E5a et E1 tandis que la seconde implémente un échantillonnage séparé. Dans les deux cas, la nécessité de filtres RF supplémentaires précédant l'échantillonnage est mise en évidence. L'atténuation minimale que doivent apporter ces filtres est spécifiée. Ces spécifications sont suffisamment dures pour qu'il ait été jugé indispensable d'effectuer une étude de faisabilité. C'est l'objet du chapitre quatre où une approche expérimentale à base d'un composant disponible sur étagère a été menée. La problématique de la gigue de l'horloge d'échantillonnage, incontournable ici eu égard à la haute fréquence des signaux à numériser, est étudiée dans le chapitre cinq. Des résultats de simulation sont présentés et un dimensionnement de la qualité de l'horloge d'échantillonnage est proposé. Dans le chapitre six, la quantification, second volet de la numérisation, est détaillée. Il s'agit très précisément du calcul du nombre minimum de bits de quantification que doit exhiber l'ADC pour représenter toute la dynamique, non seulement du signal utile mais aussi des interférences potentielles. Au vu des débits de données conséquents mis en évidence dans les chapitres trois et six, le chapitre sept évalue la possibilité de réduire la dynamique de codage du signal à l'aide de fonctions de compression. Le dernier chapitre est focalisé sur la séparation numérique des bandes E5a et E1 dans l'architecture à échantillonnage cohérent introduite au chapitre deux. Ici aussi l'atténuation minimale que doivent apporter les filtres requis est spécifiée. / This thesis studies the relevance of DS SDR architectures applied to Galileo receivers in the specific context of Civil Aviation, characterized in particular by strict requirements of robustness to interference, in particular, interference caused by DME or CW signals. The Software Defined Radio concept renders the major tendency, inside the receiver, to move the demodulation part from an analog technology to digital signal processing, that is software. The choice of this kind of design is nearly generalized in new receiver architectures so it was considered the case in this work. The Direct Sampling method consists in digitizing the signal as close as possible to the antenna, typically after the LNA and the associated RF bandpass filter. So this technique does not use any conversion to an intermediate frequency, using as much as possible the bandpass sampling principle in order to minimize the sampling frequency and consequently the downstream computational costs. What is more, this thesis aiming at the greatest simplification of the analog part of the receiver, the decision was made to suppress the analog AGC which equips the receivers of classical architecture. Only fixed gained amplifiers should precede the ADC. This document exposes the work done to determine if these choices can apply to a multifrequency (E5a and E1 signals) Galileo receiver intended for a Civil Aviation use. The structure of the document reflects the approach used during this thesis. It progresses step by step from the antenna down to the digital signal, to be processed then by the SDR part. After an introduction detailing the problem to study and its context, the second chapter investigates the Civil Aviation requirements of robustness to interference a satellite navigation receiver must comply with. It is the basis which completely conditions the design process. The third chapter is devoted to the determination of the sampling frequency. Two sampling architectures are proposed: the first implements coherent sampling of the two E5a and E1 bands while the second uses separate sampling. In both cases the necessity to use extra RF filters is shown. The minimum attenuation to be provided by these filters is also specified. These requirements are strong enough to justify a feasibility investigation. It is the subject of chapter four where an experimental study, based on a SAW filter chip available on the shelf, is related. The issue of the sampling clock jitter, of concern with the Direct Sampling technique because of the high frequency of the signal to digitize, is investigated in chapter five. Some simulation results are presented and a dimensioning of the quality of the sampling clock is proposed. In chapter six, quantization, a byproduct of digitization, is detailed. Precisely it is the calculation of the number of bits the ADC must have to digitally represent the whole dynamic of, not only the useful signal, but also of the potential interference. Considering the high binary throughput highlighted in chapters three and six, chapter seven evaluates the possibility to reduce the coding dynamic of the digital signal at the output of the ADC by means of compression functions. The last chapter is focused on the digital separation of the two E5a and E1 bands in the coherent sampling architecture presented in chapter two. Here also specifications of minimum attenuation are given. Lastly the conclusions synthesize the contributions of this thesis and proposes ideas for future work to enrich them and more generally the subject of DS-SDR Galileo receivers for Civil Aviation.
130

Impacto de condicionantes hidrológicas na definição de traçados rodoviários : aplicação na rodovia TO-247

Garcia, Lúcia Leiko Tacaoca Muraishi January 2011 (has links)
A contribuição desta pesquisa é dada através do dimensionamento dos impactos efetivos das rodovias, através da ampliação das áreas de influência para além das faixas lineares, acrescentando a avaliação da sensibilidade ambiental das bacias hidrográficas para a otimização do traçado de empreendimentos rodoviários. Foi produzida uma abordagem ordenada e sistemática das relações de causa e conseqüência nas bacias, integrando os impactos da rodovia TO-247, interligando as sedes municipais Lagoa do Tocantins e Mateiros. As sub-bacias da região da área do estudo foram classificadas mediante metodologia para estimativa de produção e transporte de sedimentos, em ambiente ArcGis ArcInfo, onde foi aplicado modelo derivado da Equação Universal da Perda de Solos (Universal Soil Loss Equation – USLE) adaptado de Wischmeier e Smith (1978) e da Relação de Distribuição de Sedimentos (Sediment Delivery Ratio – SDR) proposto por Ferro e Minacapilli (1995). Os resultados possibilitaram a classificação das sub-bacias conforme a porcentagem estimativa de carga de sedimentos que potencialmente viria a assorear os cursos d’água mediante a modificação do seu uso pela ocupação do solo induzida pela rodovia. Os critérios relevantes à definição do traçado da rodovia foram divididos em três: (1) aspectos ambientais, (2) aspectos construtivos e (3) aspectos socioeconômicos, tendo sido parametrizados através do uso de Sistema de Informação Geográfica com algoritmos em ambiente raster, na definição de caminhos de mínimo custo. A otimização da rota proposta sugere a adição de ganhos na orientação dos tomadores de decisão, como a inserção da rodovia TO-247 em bacias com menor nível de restrição de relação de aporte de sedimentos, redução das travessias sobre áreas protegidas, diminuição das obras de arte (bueiros e pontes) e da execução de cortes e aterros, incluindo a possibilidade de melhoria dos acessos aos pontos turísticos de interesse para o desenvolvimento regional. A incorporação de condicionantes hidrológicas através da classificação das bacias quanto a produção e transferência dos sedimentos destacou a principal novidade que foi a definição da área de influência delimitada pelos impactos ambientais de projetos rodoviários para os limites das bacias, podendo contribuir com o planejamento de estradas indutoras de desenvolvimento. / The contribution of this research is given by the design of effective impacts of highways, through the expansion of the influence areas beyond the linear tracks, adding the assessment of the environmental sensitivity of watersheds in order to optimize the layout of road projects. It was produced an orderly and systematic approach of the cause and consequence relations in the watersheds incorporating in it the TO-247 highway impacts, linking the cities of Mateiros and Lagoa do Tocantins. The watersheds in the region of the study area were classified using methodology for estimating production and transport of sediment in ArcGIS ArcInfo environment. It was applied the equation model derived from the Universal Soil Loss Equation - USLE adapted from Wischmeier and Smith (1978) and the Sediment Delivery Ratio - SDR according to what is proposed by Ferro and Minacapilli (1995). Those results allowed the classification of watersheds according to the percentage estimate of sediment load that would potentially silting up the waterways through modification of their usage by land use induced by the highway. The relevant criteria to define the highway route were divided into three: (1) environmental, (2) construction and (3) socioeconomic aspects, which have been parameterized by using Geographic Information System with algorithms in raster environment into the definition of low cost paths. The optimization of the route proposal in TO-247 suggests adding profit in orientation of decision makers, such as entering the highway in watersheds with lower levels of restriction regarding the amount of sediment, reduction of crossings on protected areas, reduction of culverts and bridges and the implementation of sections and embankments, including the possibility of improved access to interest tourist points for regional development. The incorporation of hydrological conditions through the classification of river watersheds as the production and transfer of sediments, which highlighted the main novelty, was the expansion circumscription of the influence area bounded by the environmental impacts of road projects for the limits of the watersheds, which may contribute to the planning of roads inducing development.

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