Landslide Prediction Method Based on a Ground-Based Micro-Deformation Monitoring Radar

As remote sensing methods have received a lot of attention, ground-based micro- deformation monitoring radars have been widely used in recent years due to their wide range, high accuracy, and all-day monitoring capability. On the one hand, these monitoring radars break through the limitations of traditional point monitoring equipment such as the Global Navigation Satellite System (GNSS) and fissure meters in terms of monitoring scope and ease of installation. On the other hand, the data types of these monitoring radars are more varied. Therefore, it may be difficult for the data-processing method of traditional point monitoring equipment to take all advantages of this type of radar. In this paper, based on time-series monitoring data of ground-based micro-deformation monitoring radars, three parameters—extent of change (EOC), extent of stability (EOS), and extent of mutation (EOM)—are calculated according to deformation value, coherence and deformation pixels size. Then a method for landslide prediction by combining these three parameters with the inverse velocity method is proposed. The effectiveness of this method is verified by the measured data of a landslide in Yunnan Province, China. The experimental results show that the method can correctly discern deformation areas and provide more accurate monitoring results, especially when the deformation trend changes rapidly. In summary, this method can improve the response rate and prediction accuracy in extreme cases, such as rapid deformation.

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OutFin, a multi-device and multi-modal dataset for outdoor localization based on the fingerprinting approach

Scientific Data ◽

10.1038/s41597-021-00832-y ◽

2021 ◽

Vol 8 (1) ◽

Author(s):

Fahad Alhomayani ◽

Mohammad H. Mahoor

Keyword(s):

Global Navigation Satellite System ◽

Urban Areas ◽

Satellite System ◽

Reference Points ◽

Navigation Satellite ◽

Data Types ◽

Entry Barrier ◽

Promising Alternative ◽

Global Navigation ◽

Global Navigation Satellite

AbstractIn recent years, fingerprint-based positioning has gained researchers’ attention since it is a promising alternative to the Global Navigation Satellite System and cellular network-based localization in urban areas. Despite this, the lack of publicly available datasets that researchers can use to develop, evaluate, and compare fingerprint-based positioning solutions constitutes a high entry barrier for studies. As an effort to overcome this barrier and foster new research efforts, this paper presents OutFin, a novel dataset of outdoor location fingerprints that were collected using two different smartphones. OutFin is comprised of diverse data types such as WiFi, Bluetooth, and cellular signal strengths, in addition to measurements from various sensors including the magnetometer, accelerometer, gyroscope, barometer, and ambient light sensor. The collection area spanned four dispersed sites with a total of 122 reference points. Each site is different in terms of its visibility to the Global Navigation Satellite System and reference points’ number, arrangement, and spacing. Before OutFin was made available to the public, several experiments were conducted to validate its technical quality.

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Copernicus Sentinel-1 MT-InSAR, GNSS and Seismic Monitoring of Deformation Patterns and Trends at the Methana Volcano, Greece

Applied Sciences ◽

10.3390/app10186445 ◽

2020 ◽

Vol 10 (18) ◽

pp. 6445 ◽

Cited By ~ 1

Author(s):

Theodoros Gatsios ◽

Francesca Cigna ◽

Deodato Tapete ◽

Vassilis Sakkas ◽

Kyriaki Pavlou ◽

...

Keyword(s):

Land Surface ◽

Surface Deformation ◽

Ground Deformation ◽

Local Population ◽

Seasonal Fluctuation ◽

Satellite System ◽

Deformation Monitoring ◽

Persistent Scatterers ◽

Geothermal Activity ◽

Global Navigation Satellite

The Methana volcano in Greece belongs to the western part of the Hellenic Volcanic Arc, where the African and Eurasian tectonic plates converge at a rate of approximately 3 cm/year. While volcanic hazard in Methana is considered low, the neotectonic basin constituting the Saronic Gulf area is seismically active and there is evidence of local geothermal activity. Monitoring is therefore crucial to characterize any activity at the volcano that could impact the local population. This study aims to detect surface deformation in the whole Methana peninsula based on a long stack of 99 Sentinel-1 C-band Synthetic Aperture Radar (SAR) images in interferometric wide swath mode acquired in March 2015–August 2019. A Multi-Temporal Interferometric SAR (MT-InSAR) processing approach is exploited using the Interferometric Point Target Analysis (IPTA) method, involving the extraction of a network of targets including both Persistent Scatterers (PS) and Distributed Scatterers (DS) to augment the monitoring capability across the varied land cover of the peninsula. Satellite geodetic data from 2006–2019 Global Positioning System (GPS) benchmark surveying are used to calibrate and validate the MT-InSAR results. Deformation monitoring records from permanent Global Navigation Satellite System (GNSS) stations, two of which were installed within the peninsula in 2004 (METH) and 2019 (MTNA), are also exploited for interpretation of the regional deformation scenario. Geological, topographic, and 2006–2019 seismological data enable better understanding of the ground deformation observed. Line-of-sight displacement velocities of the over 4700 PS and 6200 DS within the peninsula are from −18.1 to +7.5 mm/year. The MT-InSAR data suggest a complex displacement pattern across the volcano edifice, including local-scale land surface processes. In Methana town, ground stability is found on volcanoclasts and limestone for the majority of the urban area footprint while some deformation is observed in the suburban zones. At the Mavri Petra andesitic dome, time series of the exceptionally dense PS/DS network across blocks of agglomerate and cinder reveal seasonal fluctuation (5 mm amplitude) overlapping the long-term stable trend. Given the steepness of the slopes along the eastern flank of the volcano, displacement patterns may indicate mass movements. The GNSS, seismological and MT-InSAR analyses lead to a first account of deformation processes and their temporal evolution over the last years for Methana, thus providing initial information to feed into the volcano baseline hazard assessment and monitoring system.

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GNSS-ISE: Instruction Set Extension for GNSS Baseband Processing

Sensors ◽

10.3390/s20020465 ◽

2020 ◽

Vol 20 (2) ◽

pp. 465 ◽

Cited By ~ 1

Author(s):

Krzysztof Marcinek ◽

Witold A. Pleskacz

Keyword(s):

Flash Memory ◽

Low Cost ◽

Satellite System ◽

Microprocessor System ◽

Instruction Set ◽

Advantages And Disadvantages ◽

Wide Range ◽

Instruction Set Extension ◽

Baseband Processing ◽

Global Navigation Satellite

This work presents the results of research toward designing an instruction set extension dedicated to Global Navigation Satellite System (GNSS) baseband processing. The paper describes the state-of-the-art techniques of GNSS receiver implementation. Their advantages and disadvantages are discussed. Against this background, a new versatile instruction set extension for GNSS baseband processing is presented. The authors introduce improved mechanisms for instruction set generation focused on multi-channel processing. The analytical approach used by the authors leads to the introduction of a GNSS-instruction set extension (ISE) for GNSS baseband processing. The developed GNSS-ISE is simulated extensively using PC software and field-programmable gate array (FPGA) emulation. Finally, the developed GNSS-ISE is incorporated into the first-in-the-world, according to the authors’ best knowledge, integrated, multi-frequency, and multi-constellation microcontroller with embedded flash memory. Additionally, this microcontroller may serve as an application processor, which is a unique feature. The presented results show the feasibility of implementing the GNSS-ISE into an embedded microprocessor system and its capability of performing baseband processing. The developed GNSS-ISE can be implemented in a wide range of applications including smart IoT (internet of things) devices or remote sensors, fostering the adaptation of multi-frequency and multi-constellation GNSS receivers to the low-cost consumer mass-market.

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Unsupervised Human Detection with an Embedded Vision System on a Fully Autonomous UAV for Search and Rescue Operations

Sensors ◽

10.3390/s19163542 ◽

2019 ◽

Vol 19 (16) ◽

pp. 3542 ◽

Cited By ~ 15

Author(s):

Eleftherios Lygouras ◽

Nicholas Santavas ◽

Anastasios Taitzoglou ◽

Konstantinos Tarchanidis ◽

Athanasios Mitropoulos ◽

...

Keyword(s):

Embedded System ◽

Emergency Services ◽

Vision System ◽

Open Water ◽

Satellite System ◽

Search And Rescue ◽

Human Detection ◽

Primary Role ◽

Wide Range ◽

Global Navigation Satellite

Unmanned aerial vehicles (UAVs) play a primary role in a plethora of technical and scientific fields owing to their wide range of applications. In particular, the provision of emergency services during the occurrence of a crisis event is a vital application domain where such aerial robots can contribute, sending out valuable assistance to both distressed humans and rescue teams. Bearing in mind that time constraints constitute a crucial parameter in search and rescue (SAR) missions, the punctual and precise detection of humans in peril is of paramount importance. The paper in hand deals with real-time human detection onboard a fully autonomous rescue UAV. Using deep learning techniques, the implemented embedded system was capable of detecting open water swimmers. This allowed the UAV to provide assistance accurately in a fully unsupervised manner, thus enhancing first responder operational capabilities. The novelty of the proposed system is the combination of global navigation satellite system (GNSS) techniques and computer vision algorithms for both precise human detection and rescue apparatus release. Details about hardware configuration as well as the system’s performance evaluation are fully discussed.

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Application of GNSS Methods for Monitoring Offshore Platform Deformation

E3S Web of Conferences ◽

10.1051/e3sconf/20183401019 ◽

2018 ◽

Vol 34 ◽

pp. 01019

Author(s):

Khin Cho Myint ◽

Abd Nasir Matori ◽

Adel Gohari

Keyword(s):

Phase Measurement ◽

Satellite System ◽

Deformation Monitoring ◽

Offshore Platform ◽

Offshore Platforms ◽

Navigation Systems ◽

Correlated Errors ◽

Carrier Phase Measurement ◽

Satellite Navigation Systems ◽

Global Navigation Satellite

Global Navigation Satellite System (GNSS) has become a powerful tool for high-precision deformation monitoring application. Monitoring of deformation and subsidence of offshore platform due to factors such as shallow gas phenomena. GNSS is the technical interoperability and compatibility between various satellite navigation systems such as modernized GPS, Galileo, reconstructed GLONASS to be used by civilian users. It has been known that excessive deformation affects platform structurally, causing loss of production and affects the efficiency of the machinery on board the platform. GNSS have been proven to be one of the most precise positioning methods where by users can get accuracy to the nearest centimeter of a given position from carrier phase measurement processing of GPS signals. This research is aimed at using GNSS technique, which is one of the most standard methods to monitor the deformation of offshore platforms. Therefore, station modeling, which accounts for the spatial correlated errors, and hence speeds up the ambiguity resolution process is employed. It was found that GNSS combines the high accuracy of the results monitoring the offshore platforms deformation with the possibility of survey.

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The Research of Multipath and Linear Error for Pseudolites Applications

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.130-134.2890 ◽

2011 ◽

Vol 130-134 ◽

pp. 2890-2893 ◽

Cited By ~ 1

Author(s):

Xiao Guang Wan ◽

Xing Qun Zhan

Keyword(s):

Carrier Phase ◽

Indoor Environment ◽

Phase Measurement ◽

Satellite System ◽

Independent System ◽

Carrier Phase Measurement ◽

Wide Range ◽

Positioning Method ◽

Global Navigation Satellite ◽

Is Design

Pseudolites are ground-based transmitters that send global navigation satellite system like signals, such as GPS, GLONASS, or Galileo. As an independent system for indoor positioning, pseudolites technique can be explored for a wide range of positioning and navigation application where the signal of satellite GNSS can’t be received. However, with indoor environment, the positioning method of pseudolite navigation system is not entirely same as GNSS, and there are some challenging issues in research and system design. In this paper, a signal difference carrier phase measurement system with pseudolites is design. Furthermore, two major problems are studied that they are multipath error and linear errors.

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SibNet — Siberian Global Navigation Satellite System Network: Current state

Solnechno-Zemnaya Fizika ◽

10.12737/szf-44201809 ◽

2018 ◽

Vol 4 (4) ◽

pp. 82-94 ◽

Cited By ~ 2

Author(s):

Юрий Ясюкевич ◽

Yury Yasyukevich ◽

Артем Веснин ◽

Artem Vesnin ◽

Наталья Перевалова ◽

...

Keyword(s):

Global Navigation Satellite System ◽

Satellite System ◽

General Information ◽

Navigation Satellite ◽

Main Research ◽

Current State ◽

Wide Range ◽

Global Navigation ◽

Using Data ◽

Global Navigation Satellite

In 2011, ISTP SB RAS began to deploy a routinely operating network of receivers of global navigation satellite system signals. To date, eight permanent and one temporal sites in the Siberian region are operating on a regular basis. These nine sites are equipped with 12 receivers. We use nine multi-frequency multi-system receivers of Javad manufacturer, and three specialized receivers NovAtel GPStation-6 designed to measure ionospheric phase and amplitude scintillations. The deployed network allows a wide range of ionospheric studies as well as studies of the navigation system positioning quality under various heliogeophysical conditions. This article presents general information about the network, its technical characteristics, and current state, as well as the main research problems that can be solved using data from the network.

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Applying primary data from permanent stations for geodynamic zoning

Izvestiya vysshikh uchebnykh zavedenii Gornyi zhurnal ◽

10.21440/0536-1028-2021-1-54-62 ◽

2021 ◽

pp. 54-62

Author(s):

Andrei Panzhin ◽

◽

Nataliia Panzhina ◽

Keyword(s):

Rock Mass ◽

Vector Field ◽

Displacement Vector ◽

Motion Vector ◽

Satellite System ◽

Deformation Monitoring ◽

Primary Data ◽

Geodetic Measurements ◽

Degree Of Convergence ◽

Global Navigation Satellite

Introduction. The article focuses on present-day geodynamic motion in order to carry out geodynamic zoning of territories. Geodynamic monitoring may be both regional, for instance, of the Russian Federation, Ural region, geological rock mass, and it may also be local, i.e. covering a deposit and enclosing rock mass. Permanent stations of Global Navigation Satellite System (GNSS) have been used as a source of data for deformation monitoring. Methodology included the method of visualizing geodynamic motions according to the results of cyclic geodetic measurements which makes it possible to single out active geological structures, blocks, and tectonic faults on reasonable grounds. Results. It has been shown that it is advisable to use not modules of observation station displacement vector values but their velocities reduced to an annual cycle as a key source of information on geodynamic motion at large spatial-temporal bases. It has been indicated that an important characteristic of geodynamic motion vector field is divergence which characterizes the degree of convergence or divergence of a vector flux. Summary. Basic theses have been identified of the method of present-day geodynamic motions monitoring and visualization in the form of a vector field according to the results of cyclic geodetic measurements. Based on experimental data, it has been determined that the present-day geodynamic motion is vortical being the indicator of active tectonic faulting.

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Progress in Time Series Soil Moisture Retrievals Using the Cyclone Global Navigation Satellite System Mission

10.5194/egusphere-egu21-8572 ◽

2021 ◽

Author(s):

Mohammad Al-Khaldi ◽

Joel Johnson ◽

Scott Gleason

Keyword(s):

Time Series ◽

Soil Moisture ◽

Global Navigation Satellite System ◽

Satellite System ◽

Retrieval Algorithm ◽

Navigation Satellite ◽

Gps Satellites ◽

Wide Range ◽

Global Navigation ◽

Global Navigation Satellite

NASA's Cyclone Global Navigation Satellite System (CYGNSS) mission has continued to provide measurements of land surface specular scattering since its launch in December 2016. CYGNSS&#8217;s operates in a GNSS-R configuration in which &#160;CYGNSS satellites together with GPS satellites form a bistatic radar geometry with GPS satellites acting as transmitters and CYGNSS satellites acting as receivers. The fundamental GNSS-R measurement obtained using the CYGNSS observatories is the delay-Doppler map (DDM), from which normalized radar cross section (NRCS) estimates are derived. The sensitivity of CYGNSS measurements to a wide range of surface properties has motivated their use for soil moisture retrievals.This presentation reports an updated analysis of soil moisture retrieval errors using a previously reported time series soil moisture retrieval algorithm that considers a &#160;multi-year CYGNSS dataset. The presentation also reports recent progress in which further simplifications to the proposed algorithm are introduced that limit its need for ancillary soil moisture data and promote use in an operational capacity. This is accomplished, in part, through the incorporation of a recently developed global Level-1 coherence detection methodology and the use of a soil moisture climatology.Soil moisture is sensed using a time-series retrieval in which NRCS ratios derived from CYGNSS measurements are used to form a system of equations that can be solved for a times series of surface reflectivities. While the NRCS exhibits a dependence on a wide range of properties such as soil moisture, soil composition, vegetation cover, and surface roughness, NRCS ratios in consecutive acquisitions, at sufficiently low latency, exhibit a direct proportionality to reflectivity ratios that are a function of soil permittivity and therefore soil moisture. The dependence of NRCS ratios on reflectivity facilitates a location dependent inversion of reflectivity to soil moisture through a dielectric mixing model. The use of NRCS ratios however results in N-1 equations for the N soil moistures in the time series, thereby necessitating the incorporation of additional information typically expressed in terms of maximum and/or minimum soil moisture (or reflectivity) values over the time series when solving the system. These values can be obtained either from ancillary data from other systems or from a soil moisture climatology as incorporated in this presentation.Retrieved moisture values from the updated algorithm are compared against observed values reported by the Soil Moisture Active Passive (SMAP) mission. The findings suggest that there exists potential for using GNSS-R systems for global soil moisture retrievals with an RMS error on the order of 0.06 cm3/cm3 over varied terrain. The dependence of the algorithm&#8217;s retrieval error on land cover class, soil texture, and moisture variability trends will be reported in detail in this presentation.

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Validating UAS-Based Photogrammetry with Traditional Topographic Methods for Surveying Dune Ecosystems in the Spanish Mediterranean Coast

Journal of Marine Science and Engineering ◽

10.3390/jmse7090297 ◽

2019 ◽

Vol 7 (9) ◽

pp. 297 ◽

Cited By ~ 3

Author(s):

Luis Bañón ◽

José Ignacio Pagán ◽

Isabel López ◽

Carlos Banon ◽

Luis Aragonés

Keyword(s):

Low Cost ◽

Temporal Frequency ◽

Satellite System ◽

Mean Value ◽

Mediterranean Coast ◽

Unmanned Aerial Systems ◽

Aerial Photogrammetry ◽

The One ◽

Global Navigation Satellite ◽

Aerial Systems

In the past few years, unmanned aerial systems (UAS) have achieved great popularity for civil uses. One of the present main uses of these devices is low-cost aerial photogrammetry, being especially useful in coastal environments. In this work, a high-resolution 3D model of a beach section in Guardamar del Segura (Spain) has been produced by employing a low maximum takeoff mass (MTOM) UAS, in combination with the use of structure-from-motion (SfM) techniques. An unprecedented extensive global navigation satellite system (GNSS) survey was simultaneously carried out to statistically validate the model by employing 1238 control points for that purpose. The results show good accuracy, obtaining a vertical root mean square error (RMSE) mean value of 0.121 m and a high point density, close to 30 pt/m2, with similar or even higher quality than most coastal surveys performed with classical techniques. UAS technology permits the acquisition of topographic data with low time-consuming surveys at a high temporal frequency. Coastal managers can implement this methodology into their workflow to study the evolution of complex, highly anthropized dune-beach systems such as the one presented in this study, obtaining more accurate surveys at lower costs.

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