Papers & Publications
Out-of-the-box telecommunication systems thanks to our Research and Development Department
Multi-Satellite Rain Sensing: Design Criteria and Implementation Issues
2022 3rd URSI Atlantic and Asia Pacific Radio Science Meeting (AT-AP-RASC)
In this paper, we propose a novel opportunistic multi-satellite sensor system which overcomes the limitations of the conventional single-satellite solutions of the literature. The considerable robustness to the possible unavailability of some satellites, besides being well suited for powerful 2D reconstruction techniques of the rain field, makes it an appealing solution for experimental tests within national and EU-funded research projects.
Rain, Satellite broadcasting, Sea measurements, Receivers, Tomography, Sensor systems, Robustness
Improving weather radar measurements through synergy with digital broadcasting satellite receivers
URSI GASS 2021, Rome, Italy, 28 August – 4 September 2021
In the framework of the Italian project NEFOCAST , funded by regional administration of Tuscany, a commercial interactive digital video broadcasting receiver (referred as to SmartLNB) has been installed on the roof of the main building of the Institute of Atmospheric Sciences and Climate (ISAC) of Italian National Research Council (CNR) in Rome next to a laser-based Thies Clima (TC) optical disdrometer manufactured by Adolf Thies GmbH & Co, and the Polar 55C, a C-band dual-polarization scanning weather radar. This set up has been used to tune, test and validate the rainfall retrieval algorithm developed during the NEFOCAST project that allows to obtain rainfall rate from the signal-to-noise ratio measured by the SmartLNB. For the NEFOCAST aims, during the project, the Polar55C operated in pointing mode with the same elevation angle of the SmartLNB, so that the two devices could scan almost time continuously the same portion of the atmosphere (see Figure 1). In the metropolitan area of Florence, a similar setup, but with an X-band dual polarization radar, was operated for one year for extensive validation of NEFOCAST estimates. The X band radar was properly installed on the roof of the Institute of BioEconomy (IBE) of CNR in Florence and operated volume scans and Range Height Indicator (RHI) along the direction of the satellite link. In the NEFOCAST project we demonstrated the capability of using SmartLNB data to retrieve precipitation . However, theoretically, over the latter application, the SmartLNB data can be also useful to check and validate and possibly tune the attenuation correction algorithms adopted for C- and X-band weather radars. In fact, in case of intense precipitation, at those frequencies, both the reflectivity at horizontal polarization and differential reflectivity are attenuated and proper algorithms for compensating attenuation effects need to be adopted, such as those based on a relation between specific attenuation and differential phase shift. In the presence of precipitation along the Earth-satellite path, the SmartLNB measures lower values of the signal-to-noise ratio with respect to clear sky condition and therefore the attenuation due to rain drops and melting layer can be straightforward obtained for the frequency of the satellite link (namely the Ku-band frequency of 11.3458 GHz). As a consequence, the analysis of coincident measurements of radar and SmartLNB can provide useful information on the accuracy of the weather radar attenuation correction algorithm. In this study, preliminary results of latter analysis described above are presented and discussed.
Rain, Satellite broadcasting, Receivers, Sensor systems
Is Satellite Ahead of Terrestrial in Deploying NOMA for Massive Machine-Type Communications?
MDPI – Sensors Magazine – June 2021
Non-orthogonal multiple access (NOMA) technologies are considered key technologies for terrestrial 5G massive machine-type communications (mMTC) applications. It is less known that NOMA techniques were pioneered about ten years ago in the satellite domain to match the growing demand for mMTC services. This paper presents the key features of the first NOMA-based satellite network, presenting not only the underlying technical solutions and measured performance but also the related deployment over the Eutelsat satellite fleet. In particular, we describe the specific ground segment developments for the user terminals and the gateway station. It is shown that the developed solution, based on an Enhanced Spread ALOHA random access technique, achieves an unprecedented throughput, scalability and service cost and is well matched to several mMTC satellite use cases. The ongoing R&D lines covering both the ground segment capabilities enhancement and the extension to satellite on-board packet demodulation are also outlined. These pioneering NOMA satellite technology developments and in-the-field deployments open up the possibility of developing and exploiting 5G mMTC satellite- and terrestrial-based systems in a synergic and interoperable architecture.
satellite communications; massive machine type communications; Internet of Things; non orthogonal multiple access; random access
Real-time rainfall maps from satellite telecommunication signals
EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-19722,
Meteorology, Atmospheric motion vectors, Cellular phone networks, Smart Low-Noise Block converter, Kalman filter
On the Opportunistic use of Commercial Ku and Ka Band Satcom Networks for Rain Rate Estimation: Potentials and Critical Issues
CINECA IRIS Institutional Research Information System
ICASSP 2020 – 2020 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP)
In this paper we study the opportunistic use of microwave satellite signals in the Ku and Ka bands to detect the presence of rain events and to estimate their intensity. This approach, based on measuring the excess signal attenuation due to rain, has the advantage that the potential number of sensors over the territory could be increased dramatically also allowing prospectively the realization of accurate regional rain maps. Moreover, employing the same satellite network whose signals are opportunistically used, the measurements can be easily fed back and universally distributed, contributing to the effective implementation of a nowcasting platform, which could help the timely detection of catastrophic rain events. Results are very promising and show that the already good estimates obtained by using signals in the Ku band can be further improved by using signals in the Ka band. Unfortunately, as of today, the frequency with which the receivers on the Ka band provide signal measurements is too low for fast changing rain events and how to address this problem is the object of future research.
Microwave measurement, Rain, Satellites, Receivers, Attenuation measurement, Attenuation, Sensors
Exploiting the synergy between weather radar measurements and digital broadcasting satellite receivers to improve radar retrievals
11th European Conference on Radar in Meteorology and Hydrology
Locarno, Svizzera – 31st Aug – 4th Sep. 2020
weather radar, broadcasting satellite, rain measurements, C-band, X-band
The NEFOCAST System for Detection and Estimation of Rainfall Fields by the Opportunistic Use of Broadcast Satellite Signals
EEE Aerospace and Electronic Systems Magazine – June 2019
In this paper, we present results from the NEFOCAST Project, funded by the Tuscany Region, aiming at detecting and estimating rainfall fields from the opportunistic use of the rain-induced excess attenuation incurred in the downlink channel by a commercial DVB satellite signal. The attenuation is estimated by reverse-engineering the effects of the various propagation phenomena affecting the received signal, among which, in first place, the perturbations factors affecting geostationary orbits, such as the gravitational attraction from the moon and the sun and the inhomogeneity in Earth mass distribution and, second, the small-scale irregularities in the atmospheric refractive index, causing rapid fluctuations in signal amplitude. The latter impairments, in particular, even if periodically counteracted by correction maneuvers, may give rise to significant departures of the actual satellite position from the nominal orbit. A further problem to deal with is the daily and seasonal random fluctuation of the rain height and altitude/size of the associated melting layer. All of the above issues lead to nonnegligible random deviations from the dry nominal downlink attenuation, that can be misinterpreted as rain events. In this paper, we show how to counteract these issues by employing two differentially configured Kalman filters designed to track slow and fast changes of the received signal-to-noise ratio, so that the rain events can be reliably detected and the relevant rainfall rate estimated.
Received signal-to-noise ratio, NEFOCAST system, broadcast satellite signals, NEFOCAST Project, rain-induced excess attenuation, downlink channel, commercial DVB satellite signal, propagation phenomena, perturbations factors, geostationary orbits, gravitational attraction
Real-time high resolution rainfall maps from a network of ground-based interactive satellite terminals: the NEFOCAST project
Proc. IoT Vertical and Topical Summit for Agriculture, Monteriggioni, Italy, May 2018.
NEFOCAST project for real-time precipitation estimation from Ku satellite links: Preliminary results of the validation field campaign
Proc. URSI Atlantic Radio Science Meeting, Gran Canaria, Spain, May-June 2018.
NEFOCAST is a project funded by the Tuscany Region Goverment (Italy) that aims at setting up, and demonstrating through field experiments, the concept of a system able to provide precipitation maps in real-time based on the attenuation measurements collected by a dense population of interactive satellite terminals (called SmartLNB, smart Low-Noise Block converter) commercially used as bidirectional modems. The system does not require the set-up of specific precipitation measuring instruments, but uses telecommunication links. An algorithm that converts the SmartLNB raw data into attenuation values, and infers rainfall rate from the total signal attenuation provided by the devices and from the knowledge of the link geometry, has been developed. An experimental campaign will take place in 2018 in Tuscany with the purpose of validating the NEFOCAST estimates, obtained through a dense population of smartLNBs and an X-band dual-polarization weather radar, purposely installed. During a preliminary test phase, performance of the algorithm has been assessed tested by comparing data from individual smartLNBs with tipping bucket rain gauge and a co-located laser disdrometer. This study presents and discusses results obtained during the test phase, focusing on disdrometer evaluation.
rainfall rate, individual smartLNBs, preliminary test phase, X-band dual-polarization weather radar, NEFOCAST estimates, experimental campaign, link geometry, total signal attenuation, SmartLNB raw data, telecommunication links, specific precipitation measuring instruments, validation field campaign, ku satellite links, real-time precipitation estimation
The potential of SmartLNB networks for rainfall estimation
Proc. IEEE Statistical Signal Process. Workshop, Freiburg, Germany, June 2018 (invited paper)
NEFOCAST is a research project that aims at retrieving rainfall fields from channel attenuation measurements on satellite links. Rainfall estimation algorithms rely on the deviation of the measured E s /N 0 from the clear-sky conditions. Unfortunately, clear-sky measurements exhibit signal fluctuations (due to a variety of causes) which could generate false rain detections and reduce estimation accuracy. In this paper we first review the main causes of random amplitude fluctuations in the received E s /N 0 , and then we present an adaptive tracking algorithm based on two Kalman filters: one that tracks slow changes in E s /N 0 due to external causes and another which tracks fast E s /N 0 variations due to rain. A comparison of the outputs of the two filters confirms the reliability of the rainfall rate estimate.
Kalman filter; nowcasting; Rain attenuation in satellite links; rain fields evaluation; Signal Processing; Instrumentation; Computer Networks and Communications
Kalman tracking of GEO satellite signal for opportunistic rain rate estimation
Proc. Symp. Wireless Commun. Systems (ISWCS), Lisbon, Portugal, Aug. 2018.
Rain fading; Kalman filter; satellite communication; opportunistic rain rate evaluation; nowcasting.
Feasibility of Energy Management Techniques for Ultra-low Power M2M SatCom Terminals
The request for the provision of services relying on Machine to Machine (M2M) communications have increased a lot over the last years. This has led to the introduction of M2M communications also in the SatCom area. In this context, the design of ultra-low power terminals becomes indispensable. In this paper, a feasibility study for assessing the implementation of an innovative energy efficient technique for ultra-low power M2M SatCom terminals is proposed. By Ieveraging on the E-SSA (Enhanced Spread Spectrum ALOHA) protocol, the newly proposed technique jointly exploits the use of multiple Spreading Factors (SFs) for transmission together with a smart transmission manager which is able optimize the use of energy harvesting by dynamically deciding when and how to transmit data. The proposed solution has been tested in different SatCom scenarios, demonstrating its effectiveness in terms of overall throughput and energy consumption.
ultra-low power M2M SatCom terminals, E-SSA protocol, energy management techniques, Ultra-low Power M2M SatCom Terminals, ultra-low power terminals, SatCom, energy efficient technique, Machine to Machine communications, Enhanced Spread Spectrum ALOHA
Low Complexity Detectors for Spread Spectrum Receivers
In the context of the recent solutions proposed in the 3GPP for standardization group on NOMA (Non-Orthogonal Multiple Access) schemes, this paper discusses different approaches for implementing an approximate spread spectrum MMSE (Minimum Mean Square Error) detector. In addition, the implication of such detectors on the signal design is presented
spread spectrum receivers, 3GPP, standardization group,NOMA, approximate spread spectrum MMSE detector, low complexity detectors, nonorthogonal multiple access schemes, minimum mean square error detector, signal design
A new highly spread spectrum slotted burst (H3SB) protocol for satcom applications
Ka-band Conference, 2018
E-SSA, Enhanced Spread Spectrum Aloha, H3SB, ESVA, Earth Station Verification Assistance, Antenna Mapping, IOT; In Orbit Tests, Satcom-On-The-Move, SOTM, radiation pattern measurement
The Nefocast project: A nowcasting weather platform based on dual-frequency interactive satellite terminals
Proc. URSI General Assembly & Scientific Symposium, Montreal, Canada, Aug. 2017
In this paper, we present a research project named NEFO-CAST, that targets a very-short-term forecasting platform with high accuracy and small-scale spatial resolution. The innovative solution lies in adopting a new generation of interactive satellite terminals, called SmartLNB, that serves both as a weather sensor and the transceiver for the forecasting platform. Throughout the paper, we highlight the main features of the system, including the advantages compared to state-of-the-art solutions, the expected results, and the market perspectives.
Satellite broadcasting, Rain, Radio frequency, Weather forecasting, Electronic mail, Real-time systems
Exploiting satellite Ka and Ku links for the real-time estimation of rain intensity
Proc. URSI General Assembly & Scientific Symposium, Montreal, Canada, Aug. 2017
In this paper we describe a statistical and a physically based approaches to retrieve 2D rainfall fields exploiting the attenuation measurements made along satellite links at Ka and Ku bands, in the framework of the research project NEFOCAST. The retrieval algorithms, the main results obtained so far, and the on going test campaign are presented and discussed.
Real-time estimation, Rain intensity, Physically based approaches, 2D rainfall fields, Attenuation measurements, Satellite links, Retrieval algorithms, Statistical approaches, NEFOCAST
Technologies for the ground segment of the future Q/V band satellite systems: The QV-LIFT project
Proc. URSI General Assembly & Scientific Symposium, Montreal, Canada, Aug. 2017
This paper presents a summary of the project: “Q/V band earth segment Link for Future high Throughput space systems” (QV-LIFT), recently funded in the framework of the EU program Horizon 2020. The project aims at developing up to date hardware and software technologies for the Ground Segment of the future Q/V band terabit Satcom infrastructure.
Satellite ground stations, Satellite links, Ground segment, Future Q/V band terabit Satcom infrastructure, Future Q/V band satellite systems, QV-LIFT project, Q/V band earth segment Link, Future high Throughput space systems, EU program Horizon 2020
QV-LIFT project: Using the Q/V band Aldo Paraboni demonstration payload for validating future satellite systems
Proc. Ka and Broadband Commun. Conf., Trieste, Italy, Oct. 2017
In future communication satellite systems the adoption of higher frequencies as Q/V-band (around 40 GHz for downlink and 50 GHz for uplink) is seen as the promising step forward to achieve higher performance in terms of total system throughput. The envisaged usage of these frequency bands, bringing an additional 5 GHz bandwidth in each polarization (10 GHz in total), is dual: as feeder link for Fixed Satellite Service (FSS) systems and as user link for Mobile Satellite Service (MSS) for aeronautical terminals. The QV-LIFT project is paving the road for the future deployment of such Q/V-band SatCom systems, providing core technologies for both ground and user segments. The subsystems developed in the course of the project will be tested in a real environment using the Q/V-band Aldo Paraboni payload on Alphasat and its associated ground segment, made available by the Italian Space Agency (ASI). This project has been granted by the European Commission and involves a consortium of companies and universities coordinated by the Italian Space Agency (Agenzia Spaziale Italiana, ASI). The consortium consists of: Consorzio Nazionale Interuniversitario per le Telecomunicazioni (CNIT), Martel GmbH (Martel), Erzia Technologies SL (Erzia), Eutelsat S.A. (Eutelsat), M.B.I. SRL (MBI), Heriot-Watt University (HWU), SkyTech Italia SRL (SkyTech), OMMIC SAS (OMMIC). This paper presents part of the project activities, such as the description of one possible future Very High Throughput Satellite (VHTS) scenarios for Q/V-band systems. Furthermore, the technologies currently under development and the system test architecture which will be used to validate the developed technology and functionalities are presented.
Q/V-band, Fixed Satellite Service (FSS), Mobile Satellite Service (MSS), QV-LIFT project, Space Agency (ASI)
Real-time rain rate evaluation via satellite downlink signal attenuation measurement
MDPI Sensors, vol. 17, article ID 1864, 24 pages, Aug. 2017
We present the NEFOCAST project (named by the contraction of “Nefele”, which is the Italian spelling for the mythological cloud nymph Nephele, and “forecast”), funded by the Tuscany Region, about the feasibility of a system for the detection and monitoring of precipitation fields over the regional territory based on the use of a widespread network of new-generation Eutelsat “SmartLNB” (smart low-noise block converter) domestic terminals. Though primarily intended for interactive satellite services, these devices can also be used as weather sensors, as they have the capability of measuring the rain-induced attenuation incurred by the downlink signal and relaying it on an auxiliary return channel. We illustrate the NEFOCAST system architecture, consisting of the network of ground sensor terminals, the space segment, and the service center, which has the task of processing the information relayed by the terminals for generating rain field maps. We discuss a few methods that allow the conversion of a rain attenuation measurement into an instantaneous rainfall rate. Specifically, we discuss an exponential model relating the specific rain attenuation to the rainfall rate, whose coefficients were obtained from extensive experimental data. The above model permits the inferring of the rainfall rate from the total signal attenuation provided by the SmartLNB and from the link geometry knowledge. Some preliminary results obtained from a SmartLNB installed in Pisa are presented and compared with the output of a conventional tipping bucket rain gauge. It is shown that the NEFOCAST sensor is able to track the fast-varying rainfall rate accurately with no delay, as opposed to a conventional gauge.
SmartLNB, NEFOCAST, Rain field maps, Rainfall rate, Attenuation measurement
A new air-interface for affordable scada M2M services over satellite in Ku and Ka-band
Ka-band Conference, 2015
This paper describes the evolution of the ETSI S-band Mobile Interactive Multimedia (S-MIM) protocol to support Fixed Interactive Multimedia Services (F-SIM) exploiting existing Ku and Ka-band satellites. The key F-SIM protocol differences for both physical and upper layers are described and justified. The F-SIM protocol has been adopted by the recently deployed Eutelsat Broadcast Interactive System (EBIS) whose architecture, key system parameters, link budget examples and key composing elements are also described. Finally, a summary of laboratory and field trials results over the Eutelsat Ka-Sat multi-beam satellite are illustrated.
S‐MIM, Mobile satellite services, Interactive broadcast, Random access, Enhanced spread spectrum aloha, Successive interference cancellation, Software‐defined radio, S‐band, E-SSA
From S-band mobile interactive multimedia to fixed satellite interactive multimedia: making satellite interactivity affordable at Ku-band and Ka-band
International Journal of Satellite Communications and Networking (IJSCN), 2015
This paper describes the evolution of the ETSI S‐band mobile interactive multimedia protocol to support fixed satellite interactive multimedia (F‐SIM) services exploiting existing Ku‐band and Ka‐band satellites. The key F‐SIM protocol differences for both physical and upper layers are described and justified. The F‐SIM protocol has been adopted by the recently deployed Eutelsat Broadcast Interactive System whose architecture, key system parameters, link budget examples and key composing elements are also described. Finally, a summary of laboratory and field trials results over the Eutelsat KA‐SAT multibeam satellite are illustrated. Copyright © 2015 John Wiley & Sons, Ltd.
Satellite communications, Interactive television, Ka‐band, Random access, Machine to machine (M2M)
Enhanced spread spectrum aloha demodulator implementation, lab oratory tests and satellite validation
International Journal of Satellite Communications and Networking (IJSCN), 2014
This paper describes the implementation of the first enhanced spread spectrum aloha demodulator, based on an innovative architecture which combines software‐defined radio with processing via commercial graphics processing units. The validation tests performed both in laboratory conditions and directly on the satellite EUTELSAT 10A are presented. The performance assessment results obtained via satellite validate the theoretical results to a sufficient degree to make enhanced spread spectrum aloha technology a viable option for low‐power mobile and fixed terminals, thus encouraging the growth of satellite mass market applications. Copyright © 2014 John Wiley & Sons, Ltd.
S‐MIM, Mobile satellite services, Interactive broadcast, Random access, Enhanced spread spectrum aloha, Successive interference cancellation, Software‐defined radio, S‐band
Performance Assessment of the Smart mAritime saTellite terminal for mUltimedia seRvices and conteNts (SATURN) system
Advanced Satellite Multimedia Systems Conference (ASMS) and Signal Processing for Space Communications Workshop (SPSC), 2014
The following paper presents the ACCORD project which is aimed at specifying a complete platform capable of generating innovative terminals able to automatically reconfigure seamless switching between different air interfaces and relevant protocols. The ACCORD solution is a new concept comprising a platform for a family of terminals, which can be easily deployed according to the air interfaces and protocols supported. This truly innovative approach is based on three main features. Firstly a Smart router which provides seamless vertical handover by selecting the most appropriate network based on a Quality of Service policy. Secondly a Hybrid terminal on which both satellite and terrestrial waveforms are present. Lastly a Common Interface which manages the satellite and terrestrial air interfaces and their protocols using a fully Software-Defined Radio approach.
Dual-use, Hybrid, SDR, Terminal, Mobile satellite communication, Mobility management (mobile radio), Quality of service, Routing protocols, Telecommunication switching
S-MIM Field Trials Results
International Journal of Satellite Communications and Networking (IJSCN), 2013
An intelligent transport system open platform integrating the S‐band Mobile Interactive Multimedia messaging return channel protocol over satellite (based on Enhanced Spread Spectrum Aloha) has been developed and tested under real environment conditions within the framework of SafeTRIP, an FP7 EU‐funded project. This paper presents the first field trials results using the S‐band Mobile Interactive Multimedia technology. The introduced forward and return link outcomes have been derived from mobile field trials carried out in the surroundings of the German Aerospace Center (DLR) in Germany. Finally the validation of the system performances has been realized thanks to the use of a traffic emulator that can simulate a large population of Enhanced Spread Spectrum Aloha terminals. Copyright © 2014 John Wiley & Sons, Ltd.
S‐MIM, Field trials, DVB‐SH, E‐SSA, S‐band, Link layer, Power control
SATURN: Smart mAritime saTellite terminal for mUltimedia seRvices and conteNts
The following paper presents the fundamental aspects of the SATURN initiative proposed by a group of Italian companies active in developing of new solutions which exploit the potential of S-band communications. SATURN is the acronym for “Smart mAritime saTellite terminal for mUltimedia seRvices and conteNts”. Using S-band technology will make it possible to provide new services and contents on board small (10 to 24 meters) maritime vessels where satellite services are not usually enabled. The innovation of the paper is the presentation of a new cost effective solution composed of antenna, gateway and plotter in order to address the maritime market segment not covered by other bi-directional communication satellite solutions. The proposed solution will provide new satellite services currently not available while the boats are far from the coast.
Saturn, Satellites, Satellite broadcasting, Boats, Companies, Logic gates, Mobile communication, S-band, DVB-SH, E-SSA, S-MIM, SATURN
Developing ITS Services for the Open SafeTRIP Platform
4th Transport Research Arena (TRA), Athens, Greece 2012
The goal of the ongoing SafeTRIP project is to provide the ITS community with a bidirectional communications platform on which any organisation can develop its own ITS and multimedia entertainment applications. This platform is open to developers willing to benefit from a wide range of state-of-the-art satellite communications services (using the recently allocated S-band spectrum for Mobile Satellite Services and based on standards co-developed by several SafeTRIP partners), as well as almost ubiquitous terrestrial communications networks. It is also available to researchers who wish to exploit its flexibility and open standards, as well as its advanced communications capabilities. This paper briefly presents the platform architecture and focuses more specifically on case studies exemplifying the development process for three different applications. It also shows how to capitalise on the enabling functions of the platform to streamline development Finally, a number of challenges specific to the automotive environment are analysed.
Emergency Service, Transport Stakeholders, Satellite
Cooperative End To End User Services in SafeTRIP
ITS Europe Congress, Lyon, France 2011
Satellite communication can empower ITS to deploy safety critical services and services of the future, while reaching an unprecedented large number of road users in an eco-friendly and economical way. The SafeTRIP project embraces S-Band communication, creating a powerful and flexible open platform for services that road users need. In this paper, we firstly present an overview of the SafeTRIP project, the salient aspects of the platform and its communication infrastructure. Secondly, we emphasise on the focus the project has on user needs to shape services that would be supported by the SafeTRIP open platform. Finally, we describe the subset of services that have been selected on their relevance to road safety which will part of the trials and demonstrators within the project. We conclude by describing the road map and the project evolution in future.
S-Band, W2A Satellite, DVB-SH, Onboard vehicle units, Road safety, Fleet management, Mobile tv, Location-based services, Infotainment
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