Gabriella Povero

Formation of ionospheric irregularities over Southeast Asia during the 2015 St. Patrick's Day storm

We investigate the geospace response to the 2015 St. Patricks Day storm leveraging on instruments spread over Southeast Asia (SEA), covering a wide longitudinal sector of the low-latitude ionosphere. A regional characterization of the storm is provided, identifying the peculiarities of ionospheric irregularity formation. The novelties of this work are the characterization in a broad longitudinal range and the methodology relying on the integration of data acquired by Global Navigation Satellite System (GNSS) receivers, magnetometers, ionosondes, and Swarm satellites. This work is a legacy of the project EquatoRial Ionosphere Characterization in Asia (ERICA). ERICA aimed to capture the features of both crests of the equatorial ionospheric anomaly (EIA) and trough (EIT) by means of a dedicated measurement campaign. The campaign lasted from March to October 2015 and was able to observe the ionospheric variability causing effects on radio systems, GNSS in particular. The multiinstrumental and multiparametric observations of the region enabled an in-depth investigation of the response to the largest geomagnetic storm of the current solar cycle in a region scarcely reported in literature. Our work discusses the comparison between northern and southern crests of the EIA in the SEA region. The observations recorded positive and negative ionospheric storms, spread F conditions, scintillation enhancement and inhibition, and total electron content variability. The ancillary information on the local magnetic field highlights the variety of ionospheric perturbations during the different storm phases. The combined use of ionospheric bottomside, topside, and integrated information points out how the storm affects the F layer altitude and the consequent enhancement/suppression of scintillations.

N-FUELS and SOPRANO: Educational tools for simulation, analysis and processing of satellite navigation signals

In recent years, research activities in the field of Satellite Navigation have boosted worldwide. At the same time, it has become evident that few educational opportunities in the field were available for students and there was a need to develop dedicated tools for hands-on sessions. To partially answer this need, the NavSAS Group has developed N-FUELS and SOPRANO. N-FUELS, a MATLAB®-based signal simulator, allows students to understand the physical layer of the Global Navigation Satellite Systems (GNSS) signals and to learn how to manipulate them via software. SOPRANO, a collection of ANSI C language routines, implements the whole chain of GNSS signal elaboration in post-processing and enables testing and validation of new GNSS signal processing algorithms and architectures. Both tools are used in post-graduate courses at Politecnico di Torino with a high degree of internationalization, which opens interesting points of discussion concerning the introduction of novel educational tools able to meet the demand and the learning styles of students with different educational backgrounds and cultures.

Master Program on Navigation and Related Applications: a partnership between university, private sector, and international bodies.

The master program on navigation and related applications is a post-graduate study for Masters Degree on Global Navigation Satellite Systems in Italy. It is a joint initiative of Politecnico di Torino and Istituto Superiore Mario Boella, a non-profit research centre under private law. Although based in Italy, the Master Program is offered to students from around the world and English is the official language of the studies. This Program is co-sponsored by the United Nations and private industries. The United Nations Office for Outer Space Affairs provides a framework of the UN/Italy Long-term Fellowship Programme that enables the Program to solicit prospect students from developing countries through their governmental institutes and agencies related to the space applications to attend the Master courses. As to the collaboration with private industries, the Master Program is designed to include eight months of classroom learning and four months of internship with local private industries

Ionosphere monitoring in South East Asia: Activities in GINESTRA and ERICA projects

GINESTRA and ERICA are two projects funded in the framework of the ALCANTARA Initiative of the European Space Agency. GINESTRA is a survey which aims to explore the capabilities of ionosphere monitoring in South East Asia to identify both institutions involved in this field and existing monitoring facilities. ERICA exploits the GINESTRA outcomes and aims to characterize the ionospheric variability of the Equatorial Ionospheric Anomaly in the region, in particular the variation of the plasma electron density in the southern and northern crests of the anomaly and over the dip equator identified by the Equatorial Ionospheric Trough. To achieve this goal, an ad hoc measurements campaign is conducted with ground-based instruments located in the footprints of the Equatorial Ionospheric Anomaly and of the Equatorial Ionospheric Trough in Vietnam and Indonesia. The paper presents the outcomes of GINESTRA and highlights some preliminary results of the data analysis conducted so far in the framework of ERICA.

Beamforming design with partially adaptive and minimum redundancy arrays

This paper proposes a beamforming design method for interference cancellation using a special thinned array structure, termed minimum redundancy array (MRA). MRA is analyzed with partially adaptive beamforming design techniques and compared with corresponding uniform regular array (URA) over a set of likely interference scenarios. The partially adaptive beamformer design is subject to worst-case performance constraints. Extensive numerical simulations with several sets of interference scenarios show that MRA almost always outperforms URA, in both cases of fully adaptive beamformers and of partially adaptive beamformers. We also introduce a design criterion to take into account both the array geometry and partially adaptive beamforming methods.

The NAVKIT: a european multimedia tool for professional training in the field of satellite navigation technology

Satellite Navigation and its applications are becoming more and more important. In Europe, the European Commission confirmed the public funding of the European Global Navigation Satellite System (GNSS) Galileo. In this framework, new educational needs have arisen. A recently conducted survey has highlighted a general lack of educational material on GNSS-related subjects. The NAVKIT represents a first answer to the educational needs of the GNSS community. It has been designed to be a self-consistent tool for engineers or technicians not trained in navigation but it can be used also as supporting material in university lectures. The NAVKIT consists of audio-video lessons, two sets of exercises (solved exercises and problems statements), and a self-evaluation test. Ancillary parts are: Glossary, Bibliography and Questions&Answers section. The NAVKIT is HTML-based. It has been used during specific courses in Europe and in post-graduate courses in Asia. The tool was designed in a web 2.0 vision.

Analysis of the Regional Ionosphere at Low Latitudes in Support of the Biomass ESA Mission

Biomass is a spaceborn polarimetric P-band (435 MHz) synthetic aperture radar (SAR) in a dawn–dusk low Earth orbit. Its principal objective is to measure biomass content and change in all the Earth’s forests. The ionosphere introduces the Faraday rotation on every pulse emitted by low-frequency SAR and scintillations when the pulse traverses a region of plasma irregularities, consequently impacting the quality of the imaging. Some of these effects are due to total electron content (TEC) and its gradients along the propagation path. Therefore, an accurate assessment of the ionospheric morphology and dynamics is necessary to properly understand the impact on image quality, especially in the equatorial and tropical regions. To this scope, we have conducted an in-depth investigation of the significant noise budget introduced by the two crests of the equatorial ionospheric anomaly (EIA) over Brazil and Southeast Asia. This paper is characterized by a novel approach to conceive a SAR-oriented ionospheric assessment, aimed at detecting and identifying spatial and temporal TEC gradients, including scintillation effects and traveling ionospheric disturbances, by means of Global Navigation Satellite Systems ground-based monitoring stations. The novelty of this approach resides in the customization of the information about the impact of the ionosphere on SAR imaging as derived by local dense networks of ground instruments operating during the passes of Biomass spacecraft. The results identify the EIA crests as the regions hosting the bulk of irregularities potentially causing degradation on SAR imaging. Interesting insights about the local characteristics of low-latitudes ionosphere are also highlighted.

G-TRAIN Supporting Education and Training in the Field of Satellite Navigation in Europe

The aim of the G-TRAIN project is to set up a framework for higher education addressing different academic (MSc, Specialising Master and PhD) and networking activities. Indeed, it has been identified that on the one hand there are not enough people trained in the field of satellite navigation in Europe to support the finalization of the Galileo system as well as the foreseen development of satellite navigation applications and on the other hand there are no “European GNSS education” only activities. The goal of the project is to set up a long-term model for the coordination of universities, students exchanges and researchers co-operation in order to exploit synergies and to cover all the different needs of GNSS training, expressed by both industry and research worlds. The paper describes the achievements already obtained in the first part of the project lifetime and its future activities.

Work in progress — GnssEduPack: An innovative approach to education and training in the field of Global Navigation Satellite Systems

The aim of this paper is to introduce the GnssEduPack, which is a training kit in the field of Global Navigation Satellite System (GNSS) which is oriented towards university students and GNSS application developers. The whole idea behind the GnssEduPack is to provide students with a new tool, which, beside providing theoretical background and explanations, allows for consistent experimental activity with real GNSS signals thus bringing the student directly in contact with practice. The key feature of the GnssEduPack is the emphasis on practical problems of real GNSS oriented engineering, which is made possible by the use of the SAT_SURF Suite, a light, compact and easy-to-use hardware/software experimental platform.

Building Links between Europe and South-East Asia in the Field of EGNSS: the BELS Project and the NAVIS Centre

South East Asia is growing at an impressive pace with its GDP having increased by about 350% in ten years , ri sing from 650 Billion