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Ranging signals in the urban environment suffer from significant attenuation and additive errors caused by reflections. Special design considerations for ranging-based positioning systems that operate in the Urban Canyon are presented. The tradeoff between acquisition sensitivity and acquisition time is presented. The integrity of the measurements is improved by verifying that the signals exhibit...
This paper makes improvements aiming at the existing problems of hybrid location algorithm combining BS and satellites data and propose the TDOA/DGPS hybrid location algorithm based on the initial estimation. According to simulations with MATLAB, this new algorithm is proved to improve positioning accuracy further and reduce the amount of computation. But this algorithm can not eliminate effect of...
Remotely sensed data is only a key source of detection of Earth's surface changes or Land-Use/Land-Cover (LULC) monitoring. During past decades, a series of effective change detection techniques such as Principal Component Analysis (PCA), Change Vector Analysis (CVA) and Post Classification Comparison (PCC), have been developed to observe the LULC vicissitudes. All aforesaid techniques performed very...
In this paper, we propose an adaptive tracking channel control mechanism for GNSS receivers in weak signal applications powered by renewable energy sources. The proposed technique dynamically adjusts tracking channels to get better time coverage and positioning availability under the desired accuracy requirement. A low-complexity hardware architecture is developed for power management and adaptive...
This paper investigates a new approach for flood evaluation based on multi-sensor satellite images utilizing swarm intelligence techniques. The swarm intelligence techniques used are Genetic Algorithm (GA) for image registration and Niche Particle Swarm Optimization (NPSO) for image clustering. Analysis of satellite images are applied in two stages: Linear Imaging Self Scanning Sensor (LISS-III) image...
Monitoring and analysis of the land and rapid environmental change, leads to the use of Land Use and Land Cover (LULC) classification approaches from remote sensing data. The main focus of this aper is to illustrate the practical approach to analysis and mapping of land use and land cover features using high resolution satellite images. The study is carried out for two different places, Basel and...
Positioning techniques are known in a wide variety of wireless radio access technologies. Traditionally, Global Positioning System (GPS) is the most popular outdoor positioning system. Localization also exists in mobile networks such as Global System for Mobile communications (GSM). Recently, Wireless Local Area Networks (WLAN) become widely deployed, and they are also used for localizing wireless-enabled...
With the continuous development and improvement of GNSS, the multi-constellation will be the main navigation mode in the future. Dilution of precision (DOP) has been widely used as an accuracy metric and for navigation and tracking systems. Properties of DOP in multi-constellation are one of the crucial elements to be studied. In this paper, theoretical analysis and simulation has been made in GDOP...
Differential Global Positioning System (DGPS) is a technique to improve the accuracy of the GPS positioning. In DGPS, error correction signal is transmitted to the surrounding rovers. Any correction loss during transmission may lead to navigation inaccuracy. This problem can be minimized by incorporating Dynamic Neural Networks (DNNs) at the rovers. DNNs can be used to predict the present and future...
Global Positioning System (GPS) is the emerging technology extending its applications in the field of surveying, navigation, military etc., and these applications demands multiple levels of accuracy ranging from tens of meters to sub-millimetre level. Hence there is a need to develop systems, methods and a technique to meet the demand of high accuracy.GPS provides its services in two different standards,...
With the discontinuity of Selective Availability (SA) by U.S government, obtaining accuracies upto tens of meters by GPS system became simpler. Though the performance level reached to millimeter level accuracy, it is only restricted to military domains and is provided under Precise Positioning Service (PPS) standards. The two different GPS services include PPS and Standard Positioning Service (SPS)...
The Texture Feature Extraction (TFE) plays an important role in satellite image processing application. This paper proposes a novel method for Satellite Imagery Classification. Our proposed method is a combination of Local Binary Pattern (LBP) and Fuzzy c-means classification algorithm. Local Binary Pattern is calculated by thresholding a 3 × 3 neighborhood of each pixel by the center pixel value...
In this paper three images of Land sat TM data of 1987, 2001 and 2010 being used to analyze the land cover and land use LC/LU changes in Algiers areas. The paper followed the expansion of urban tissue and its effect of decreasing agricultural and bare soil lands using difference soil adjusted vegetation index DSAVI, difference Greenness Tasseled Cap transformation DGTCT and post classification of...
Cooperative approaches are becoming of great interest in automotive research. One of the most important ITS applications is cooperative localization. In this paper, the concept of a dynamic base station DGPS (DDGPS) and its application in the vehicular cooperative localization is introduced and discussed. The DDGPS is a decentralized cooperative method which aims to improve the GPS positioning by...
Although rule-based object-based classification can often perform better than the supervised approaches, its attribute selection is very time consuming and hardly transferable between different urban areas. The purpose of this study is to identify transferable rule-sets for different areas from QuickBird satellite imagery for urban areas consisting heterogeneous man-made and natural features. Object-based...
Nowadays smartphones are equipped with various sensors and powerful processing modules, and are accessible to flexible communication networks, thus enabling complex applications such as context awareness, activity recognition, health care monitoring and so forth. These applications typically require contextual information to optimize the effectiveness, e.g. indoor/outdoor identification. This paper...
Images captured by Lapan-A3 pushbroom imager will have some geometric distortions from various sources. Most of them can be ideally corrected by using a high quality ancillary data, i.e. Lapan-A3 attitude sensor must provide attitude data for each image line (2,5ms) and free from measurement error. That ideal condition is nearly impossible to achieve so this paper aims to determine the minimum performance...
In this paper1, we propose an aerospace relay-based positioning scheme for regional positioning in the battlefield where a global navigation satellite system (GNSS) is not available because of signal jamming or blocking. In the proposed scheme, aeronautical nodes and satellites, called aerospace nodes, are used to relay a navigation signal broadcast from ground reference stations. The user receives...
In this paper, VRS network-RTK for vehicle in downtown is analyzed. As a result, it shows around 2.85m position error in eliminating points splashed by ones. It can be applied to vehicle positioning for vehicle safety services, if vehicle positioning with network-RTK has process of Sig in GPGGA, state, speed.
A topographic correction method has been developed for TM images of rugged terrain, using ASTER stereo image pairs as a key input. The difference in solar radiance as a result of topography has always been a major barrier to the research on quantitative remote sensing in rugged areas. The mountain radiative transfer model with strict physical meaning must be selected to eliminate terrain effects....
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