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The current paper presents a methodology for generating kinematic sensor maps of train journeys on railway tracks, by using a crowdsourced approach to data collection. In order to create uniform data representation and accuracy oriented maps of railway tracks, different concepts relating to satellite imagery analysis belonging to the domain Earth Sciences have been used. Additionally by optimizing...
TanDEM-X is an innovative spaceborne X-band SAR mission designed to derive a digital elevation model (DEM) of the Earth's land surface with an unprecedented relative vertical accuracy of 2m at a 12m posting. The global DEM is derived from interferometric SAR acquisitions performed by two radar satellites flying in close orbit formation, with adjustable baselines in cross- and in along-track directions...
Study of the land cover classification using multi-source data are very important for eco-environment monitoring, land use planning and climatic change detection. In this study, the utility of multi-source RADARSAT-2 and LANDSAT-8 multi-spectral images for improving land cover classification performance using Support Vector Machine (SVM) classifier. HH polarized C band RADARSAT-2 images were fused...
Motivated by the emergence of the Internet of Things (IoT), and by the importance that location information has on many complex systems scenarios, we propose a hybrid scheme for user positioning in an urban scenario. The system uses both a Global Navigation Satellite System (GNSS) and a Magnetic Positioning System (MPS). To maintain receiver complexity and cost at a minimum, the location scheme combines...
For the GNSS receiver, when the satellite navigation signal is weak, the traditional tracking accuracy of GNSS receiver tracking loops will decline sharply which will lead to the deterioration of the Carrier frequency error. Aiming at improving the Velocity Determination accuracy of GNSS receiver, we propose the GNSS Precise Velocity Determination Algorithm Based on Chaotic Oscillator. The proposed...
The increase of the frequency of Earth-Low Earth Orbit satellite links leads to the development of new propagation models in order to accurately characterize the propagation channel. Space-time models are developed for tropospheric attenuation and scintillation but their validation is difficult in the absence of measured data. The verification of scintillation models can be performed worldwide against...
Future telecommunication satellites are built with increasing antenna sizes and possess high demands on antenna measurement facilities. AIRBUS Defence & Space Compensated Compact Ranges (CCRs) are highly accurate facilities for antenna and payload testing. However, facilities of type CCR 75/60 have a quiet zone size of approximately 5 m diameter which can become critical for future satellite applications...
Modernization in industry and urban expansion has led to serious landscape problems and increased pressure on several environmental features i.e. deforestation, climate change etc. Therefore, it is necessary to identify the land use change to minimize the input of the transformation. Remote sensing and GIS considered as one of the potential methods to monitor the land use changes. This study investigate...
Aiming at the problem of how to make use of the atomic clocks offered by Micro-PNT to make Global Navigation Satellite System (GNSS) receivers fulfill fast positioning with the recovery of the satellite navigation signal, this paper discusses the fast positioning method which omits the step of frame synchronization and proposes a constellation-triangle selecting algorithm based on high-precision clock...
The advancement in remote sensing and GIS technologies make it possible to be an effective instrument to extract information of the earth's surface such as temperature without being in direct contact. The satellite imagery of the Landsat Operational Land Imager (OLI) that was launched in 2014 with enhancement of two additional thermal bands as compared to Landsat Thematic Mapper (TM) of only one thermal...
This paper describes, and illustrates using documented applications, a general framework methodology for wide-area forest and land use mapping and change detection using Synthetic Aperture Radar (SAR) remote sensing. Consideration is given to implementation of the SAR-based methodology using both commercial and free/open-source software. Our experience shows that constructing a complete processing...
In this paper, we analysed and compared the digital elevation model (DEM) based on high resolution QuickBird and Pleiades satellite stereo images. 3D maps were generated for objects like trees near poles of power transmission lines using satellite stereo images. This study was very challenging due to weather condition, hilly and non-uniform terrain at Kota kina balu in East Malaysia. First we require...
This study is aimed at evaluating the trade-off between Global Positioning System (GPS) accuracy and power saving from reduction of number of channels. The study is conducted for number of GPS receiver channels of 4 to 12 for two scenarios: 1) Normal scenario with full range of available GPS satellites; 2) Obstruction scenario with GPS satellite elevation cutoff of 20°. It is observed that increase...
The Advanced Land Observing Satellite-2 (ALOS-2) was launched from Tanegashima Space Center by H-IIA rocket successfully on 24th May 2014. The Phased Array type L-band Synthetic Aperture Radar-2 (PALSAR-2) is the state-of-the-art L-band SAR system which succeeds to PALSAR onboard ALOS. PALSAR-2 uses almost whole bandwidth allocated for L-band active sensor of Earth Exploration Satellites Service specified...
Road damage detection from high-resolution remote sensing image is critical for natural disaster investigation and disaster relief. In a disaster context, the pair of pre-disaster and post-disaster road data for change detection are difficult to obtain due to the mismatch of different data sources, especially for rural areas where the pre-disaster data (i.e. remote sensing imagery or vector map) are...
An important aspect of research in the remote sensing field is to objectively compare different classifiers. This is the foundation of hundreds of research projects and in this paper we will address some raising concerns when evaluating solutions for classification of data sets with skewed class distributions. The quality of assessment is based on the problem specified by the user and the corresponding...
On-orbit geometric calibration is a critical and essential step to guarantee the high geometric positioning accuracy of high-resolution optical satellite imagery. In this paper, we first review and summarize the on-orbit geometric calibration methods for high-resolution optical satellite and then analyze their advantages and disadvantages. Finally, we present our perspective on on-board geometric...
In this paper a new approach from the combination of band ratioing function and MLP Neural Networks technique is proposed to differentiate between clouds and background in Landsat ETM+ and MSG SEVIRI data. First, in order to increase the contrast of the clouds and background, a band ratioing function is applied to each sub-image. Second, the sub-images are segmented by MLP Neural Networks technique...
The project aerosol-CCI as part of European Space Agency (ESA) Climate Change Initiative (CCI) has provided three aerosol retrieval algorithms for the Advanced Along-Track Scanning Radiometer (AATSR) aboard on ENVISAT. For the purpose of estimating different performance of these three algorithms in Asia, in this paper we compared the Aerosol Optical Depth (AOD) of L2 data (10km×10km) including FMI...
We apply two algorithms to full-wave analysis of electrically large reflector antennas with complex surroundings. The new algorithms are a higher-order MLFMM, yielding a considerably faster solution than a low-order MLFMM, and a fast algorithm for current integration. The new techniques allow a significant reduction of the computational burden, thereby extending the range of problems that can be solved...
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