scholarly journals Save Our Roads from GNSS Jamming: A Crowdsource Framework for Threat Evaluation

Sensors ◽  
2021 ◽  
Vol 21 (14) ◽  
pp. 4840
Author(s):  
Roi Yozevitch ◽  
Revital Marbel ◽  
Nir Flysher ◽  
Boaz Ben-Moshe
Keyword(s):  
Field Experiments ◽  
Region Of Interest ◽  
Detection Algorithm ◽  
Global Navigation Satellite Systems ◽  
Dynamic Phenomenon ◽  
Satellite Systems ◽  
The World ◽  
Jamming Detection ◽  
Global Navigation Satellite ◽  
Coverage Map

Global Navigation Satellite Systems (GNSS) jamming is an acute problem in the world of modern navigation. As more and more applications rely on GNSS for both position and timing, jamming ramifications are becoming more severe. In this paper we suggest a novel framework to cope with these threats. First, a Bayesian jamming detection algorithm is introduced. The algorithm can both detect and track several jammers in a pre-defined region of interest. Then, a jamming coverage map algorithm is offered. Similar to cellular 3G/4G coverage maps, such a map can detect “weak” GNSS reception spots and handle them. Since jamming interference can be a dynamic phenomenon (e.g., a vehicle equipped with a jammer), the coverage map changes with time. Thus, interference patterns can be detected more easily. Utilizing the offered algorithm, both on simulation and field experiments, we have succeeded to localize an arbitrary jammer(s) within the region of interest. Thus, the results validate the viability of the proposed method.

scholarly journals CODE IGS reference products including Galileo

2020 ◽  
Author(s):  
Lars Prange ◽  
Arturo Villiger ◽  
Stefan Schaer ◽  
Rolf Dach ◽  
Dmitry Sidorov ◽  
...  
Keyword(s):  
Rapid Analysis ◽  
Global Navigation Satellite Systems ◽  
Processing Strategy ◽  
International Gnss Service ◽  
Satellite Systems ◽  
The World ◽  
Product Generation ◽  
Clock Correction ◽  
Global Navigation Satellite ◽  
The Impact

<p>The International GNSS service (IGS) has been providing precise reference products for the Global Navigation Satellite Systems (GNSS) GPS and (starting later) GLONASS since more than 25 years. These orbit, clock correction, coordinate reference frame, troposphere, ionosphere, and bias products are freely distributed and widely used by scientific, administrative, and commercial users from all over the world. The IGS facilities needed for data collection, product generation, product combination, as well as data and product dissemination, are well established. The Center for Orbit Determination in Europe (CODE) is one of the Analysis Centers (AC) contributing to the IGS from the beginning. It generates IGS products using the Bernese GNSS Software.</p><p> </p><p>In the last decade new GNSS (European Galileo and Chinese BeiDou) and regional complementary systems to GPS (Japanese QZSS and Indian IRNSS/NAVIC) were deployed. The existing GNSS are constantly modernized, offering - among others - more stable satellite clocks and new signals. The exploitation of the new data and their integration into the existing IGS infrastructure was the goal of the Multi-GNSS EXtension (MGEX) when it was initiated in 2012. CODE has been participating in the MGEX with its own orbit and clock solution from the beginning. Since 2014 CODE’s MGEX (COM) contribution considers five GNSS, namely GPS, GLONASS, Galileo, BeiDou2 (BDS2), and QZSS. We provide an overview of the latest developments of the COM solution with respect to processing strategy, orbit modelling, attitude modelling, antenna calibrations, handling of code and phase biases, and ambiguity resolution. The impact of these changes on the COM products will be discussed.</p><p> </p><p>Recent assessment showed that especially the Galileo analysis within the MGEX has reached a state of maturity, which is almost comparable to GPS and GLONASS. Based on this finding the IGS decided to consider Galileo in its third reprocessing campaign, which will contribute to the next ITRF. Recognizing the demands expressed by the GNSS community, CODE decided in 2019 to go a step further and consider Galileo also in its IGS RAPID and ULTRA-RAPID reference products. We summarize our experiences from the first months of triple-system (ULTRA)-RAPID analysis including GPS, GLONASS, and Galileo. Finally we provide an outlook of CODE’s IGS analysis with the focus on the new GNSS.</p>

scholarly journals The Global Navigation Satellite Systems Reflectometry (GNSS-R) Microwave Interferometric Reflectometer: Hardware, Calibration, and Validation Experiments

Sensors ◽  
2019 ◽  
Vol 19 (5) ◽  
pp. 1019 ◽  
Author(s):  
Raul Onrubia ◽  
Daniel Pascual ◽  
Jorge Querol ◽  
Hyuk Park ◽  
Adriano Camps
Keyword(s):  
Field Experiments ◽  
Beam Steering ◽  
Calibration Procedure ◽  
Global Navigation Satellite Systems ◽  
Dual Band ◽  
Navigation Satellite ◽  
Satellite Systems ◽  
Calibration And Validation ◽  
Global Navigation Satellite ◽  
Validation Experiments

This manuscript describes the Microwave Interferometric Reflectometer (MIR) instrument, a multi-beam dual-band GNSS-Reflectometer with beam-steering capabilities built to assess the performance of a PAssive Reflectrometry and Interferometry System—In Orbit Demonstrator (PARIS-IoD) like instrument and to compare the performance of different GNSS-R techniques and signals. The instrument is capable of tracking up to 4 different GNSS satellites, two at L1/E1 band, and two at L5/E5 band. The calibration procedure of the up- and down-looking arrays is presented, the calibration performance is evaluated, and the results of the validation experiments carried out before the field experiments are shown in this paper.

scholarly journals GNSS Receivers, Theirs Features, User Environment And Applications

2014 ◽  
Vol 21 (1) ◽  
pp. 49-58
Author(s):  
Jacek Januszewski
Keyword(s):  
World Market ◽  
Global Navigation Satellite Systems ◽  
Main Task ◽  
Navigation Satellite ◽  
Performance Parameters ◽  
Satellite Systems ◽  
The World ◽  
Gnss Receivers ◽  
Global Navigation Satellite ◽  
The Given

AbstractSince many years the coordinates of the position can be obtained with the use of satellite navigation and augmentation systems, SNS and SBAS, respectively. All these systems are called GNSS (Global Navigation Satellite Systems). The main task of the user segment is to transform the products delivered by the GNSS infrastructure into services that users are mainly interested in. That's why GNSS receiver selection depends on user application. Nowadays several hundred different receivers provided by more than one hundred manufacturers are available on the world market. The review of the performance parameters of GNSS receivers accessible in 2014 and last three years is presented in this paper. Additionally the paper gives the reply to some important questions as: for how many applications the given model is destined, which is the percentage of the receivers designed for marine and navigation users, which equipment features of the receiver are the most important for given application, which satellite signals apart from GPS signals can be tracked in the receiver?

scholarly journals The Identification of Possible Applications of the E-Loran System

2018 ◽  
Vol 25 (1) ◽  
pp. 165-186
Author(s):  
Krzysztof Czaplewski ◽  
Adam Weintrit
Keyword(s):  
Human Activity ◽  
Global Navigation Satellite Systems ◽  
Time Signal ◽  
Navigation Satellite ◽  
Effective Protection ◽  
Satellite Systems ◽  
The World ◽  
Global Navigation ◽  
Global Navigation Satellite ◽  
Potential Tool

AbstractGlobal Navigation Satellite Systems (GNSS) more and more affect many areas of human activity in the world. Every day human activity around the world depends upon satellite systems for positioning, navigation and timing. As these systems are commonly used further efforts must be made to make GNSS more immune to on occurring more and more frequently incidents of jamming and spoofing. It seems that eLoran system is currently the best the technical and scientific solution to allowing for effective protection of the Global Navigation Satellite Systems. Last year the authors presented eLoran system as a potential tool for transmission of the national time signal [Curry et al., 2017]. This time the authors present abilities of additional use of the eLoran as a back-up system for GNSS.

Hydrogeophysical Survey of Groundwater Development at Okada Community Ovia North – East L.G.A. Edo State

2018 ◽  
Vol 2 (1) ◽  
pp. 39-45
Author(s):  
M. O. Ehigiator
Keyword(s):  
Global Navigation Satellite Systems ◽  
Geophysical Investigation ◽  
Satellite Systems ◽  
North East ◽  
Long Time ◽  
Electrical Sounding ◽  
Edo State ◽  
Global Navigation Satellite ◽  
Water Problems ◽  
Aquifer Unit

Geophysical investigation was conducted at Okada community in ovia North Local Govertment area of Edo state to determine the prospect of aquifer zone. The Petrozenith PZ-02 Terrameter, one of the Electrical Resistivity Equipment was used to conduct a Vertical Electrical Sounding (VES) in the study area. The Garmin Etrex 10 Global Navigation satellite systems (GNSS) was used to acquire Geodetic coordinates of point where VES observations were made. This research was carried out as a pre-drilling Hydro-geophysical survey conducted for the purpose of surveying and studying the proposed water borehole site at Okada Community that has suffered acute water problems for a very long time. There have been series of boreholes drilled in the studied area but all are dry wells. This survey was conducted to investigate the subsurface complexity of the sites in respect of lithology and to recommend the total drill depth based on the prospective aquifer unit so identified. Result of interpretation suggests that the area is underlain with substantive aquiferous formation but at a depth not exceeding 121.60 m (398.95 ft), which is the lower aquifer unit. The value of elevation at point of observation referenced to mean sea level is 94 m.

scholarly journals Forty-three years of absolute gravity observations of the Fennoscandian postglacial rebound in Finland

2021 ◽  
Vol 95 (2) ◽  
Author(s):  
Mirjam Bilker-Koivula ◽  
Jaakko Mäkinen ◽  
Hannu Ruotsalainen ◽  
Jyri Näränen ◽  
Timo Saari
Keyword(s):  
Gravity Data ◽  
Gravity Change ◽  
Global Navigation Satellite Systems ◽  
Absolute Gravity ◽  
Data Sets ◽  
Postglacial Rebound ◽  
Land Uplift ◽  
Satellite Systems ◽  
Gravity Measurements ◽  
Global Navigation Satellite

AbstractPostglacial rebound in Fennoscandia causes striking trends in gravity measurements of the area. We present time series of absolute gravity data collected between 1976 and 2019 on 12 stations in Finland with different types of instruments. First, we determine the trends at each station and analyse the effect of the instrument types. We estimate, for example, an offset of 6.8 μgal for the JILAg-5 instrument with respect to the FG5-type instruments. Applying the offsets in the trend analysis strengthens the trends being in good agreement with the NKG2016LU_gdot model of gravity change. Trends of seven stations were found robust and were used to analyse the stabilization of the trends in time and to determine the relationship between gravity change rates and land uplift rates as measured with global navigation satellite systems (GNSS) as well as from the NKG2016LU_abs land uplift model. Trends calculated from combined and offset-corrected measurements of JILAg-5- and FG5-type instruments stabilized in 15 to 20 years and at some stations even faster. The trends of FG5-type instrument data alone stabilized generally within 10 years. The ratio between gravity change rates and vertical rates from different data sets yields values between − 0.206 ± 0.017 and − 0.227 ± 0.024 µGal/mm and axis intercept values between 0.248 ± 0.089 and 0.335 ± 0.136 µGal/yr. These values are larger than previous estimates for Fennoscandia.

Sign in / Sign up

Export Citation Format

Share Document