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Chamois-Arsene
No full textChamois Arsene is a fork of CompCert, the formally verified C compiler.# OverviewThe CompCert C verified compiler is a compiler for a large subset of the C programming language that generates code for the PowerPC, ARM, x86 and RISC-V processors.The distinguishing feature of CompCert is that it has been formally verified using the Coq proof assistant: the generated assembly code is formally guaranteed to behave as prescribed by the semantics of the source C code.For more information on CompCert (authors, supported platforms, supported C features, installation instructions, using the compiler, etc), please refer to the Web site and especially the user's manual.# Chamois Arsene versionChamois Arsene is an extension of Chamois CompCert with security counter-measures.Chamois CompCert is a version of CompCert with additions from Verimag and previously from Kalray (a chamois is a fast and agile caprine, very common in French Alps)
Efficient error-correcting codes for the HQC post-quantum cryptosystem
No full textInternational audienceThe HQC post-quantum cryptosystem enables two parties to share noisy versions of a common secret binary string, and an error-correcting code is required to deal with the mismatch between both versions. This code is required to deal with binary symmetric channels with as large a transition parameter as possible, while guaranteeing, for cryptographic reasons, a decoding error probability of provably not more than 2 -128 . This requirement is non-standard for digital communications, and modern coding techniques are not amenable to this setting. This paper explains how this issue is addressed in the last version of HQC: precisely, we introduce a coding scheme that consists of concatenating a Reed-Solomon code with the tensor product of a Reed-Muller code and a repetition code. We analyze its behavior in detail and show that it significantly improves upon the previous proposition for HQC, which consisted of tensoring a BCH and a repetition code. As additional results, we also provide a better approximation of the weight distribution for HQC error vectors, and we remark that</div
Communications numériques
No full textLicenceConnaissances de bases en communications numériques selon le référentiel Atsep établi par la Commission Européenne, nécessaires pour aborder les thèmes CNS (Communication, Navigation, Surveillance)
Array Processing: ENAC class of array processing for ASNAT second year and IENAC SAT third year students
No full textMaste
FOCUS: an Intelligent Startle Management Assistant for Maximizing Pilot Resilience
No full textInternational audienceOn the flight deck, the startle effect is triggered by sudden, unexpected and possibly threatening events such as bird strikes or system failures. It is a very rapid protective and defensive reaction that can lead to a partial or total incapacitation of pilots with tragic consequences. With Single Pilot and Reduced Crew operations likely being implemented in the future, the single pilot will be forced to face and handle the startle effect alone in the cockpit. We designed and developed FOCUS (Flight Operational Companion for Unexpected Situations), an intelligent assistant designed to help single pilots overcome the startle effect. FOCUS supports pilots in regulating their stress and maintaining an adequate situational awareness. The assistant guides them to breathe at a specific pace thanks to ambient light brightness variation of the cockpit and draws their attention towards potentially unseen information. To test and improve its design, we evaluated FOCUS in an A320 simulator with five qualified pilots. In these trials, FOCUS was positively welcomed by pilots as they perceived it as a valuable addition to the cockpit. These evaluations will guide further iterations of FOCUS design and support the understanding of human-AI teaming in the cockpit in subsequent studies
Strategic Path Change Maneuvers for Weather Obstacle Avoidance in Aviation
No full textInternational audienceWeather avoidance algorithms play a crucial role in significantly enhancing aircraft safety during flight operations,particularly in the presence of severe weather conditions. This paper presents a novel obstacle avoidance strategy basedon the use of alternative paths to circumvent obstacles during the cruise phase. The objective of this study is to assessthe benefits of using strategic information to address tactical avoidance issues. Firstly, the new strategy is simulated in astatic and then dynamic space populated with weather obstacles. Subsequently, the proposed strategy is compared to aclassical avoidance maneuver in several dynamic simulations, varying the size of the obstacles and the detection rangeof the radar. The results show that including strategic information on dynamic rerouting can be of significant benefitto both the pilot and air traffic controller, providing a supportive decision-making tool for bad weather avoidance
First Steps of Designing Adaptable User Interfaces to Mediate Human-Robot Interaction
No full textInternational audienceThere is a wide diversity of platforms for teleoperating robots. Every robot, use case, and type of user brings a unique set of expectations. We propose that human-robot interaction should consider the opportunity to use an external device (such as a smartphone) to not only teleoperate but also mediate the interaction with a robot, either in telepresence or in co-presence. In this paper, we present first steps and ideas towards the development of this media. It involves, as first end-users, the members of the robotics department of our laboratory and considers all robotic platforms which are hosted there (assistance robots, terrestrial robots, robots humanoids, quadrupeds, etc.). We describe our user-centred design methodology, detailing the needs analysis and brainstorming sessions conducted. Following this, we outline the design and prototyping phases, showcasing the iterative development of our interface. Finally, we discuss the results from our evaluations and the implications for future work in creating flexible and inclusive interfaces for diverse user groups
DME/TACAN Multipath Impact on GNSS L5/E5a Airborne Receivers Part I: C/N0 Degradation Model
No full textInternational audienceThis article is the first part of a two-part manuscript addressing the DME/TACAN multipath (MP) impact on the future airborne GNSS Dual-Frequency Multi-Constellation (DFMC) GNSS L5/E5a receiver. GNSS L5/E5a signals and DME/TACAN pulsed signals share the same Aeronautical Radionavigation Service frequency band with consequent interference. The interference is characterized in civil aviation standards by the GNSS signal C/N0 degradation model at the DFMC correlator input. This model assumes the presence of a temporal blanker at the DMFC Radio-Frequency Front-End block output to mitigate the DME/TACAN pulsed signals. It relies on the definition of the above blanker pulse width (pweq) and the below blanker equivalent pulse width (PWeq). However, this model did not consider the presence of DME/TACAN pulsed signals MP. Therefore, the objective of this paper is to propose two revised version of the C/N0 degradation model, the statistical and the fixed environment models, where the impact of the DME/TACAN MP is accounted for by an updated formula of pweq and PWeq. The MP modeling is especially important at low altitude where data measurement campaigns have highlighted the MP impact on the temporal blanker. Both models are designed to cover different needs: the statistical model is a low complexity model completely defined by closed-form formulas designed for standardization purposes, and the fixed environment model is a high complexity model able to provide the C/N0 degradation for any specific set of DME/TACAN signal conditions, which is used in this work to inspect the limitations of the statistical model
U-spaceChain: A Decentralized Approach to Unmanned Traffic Management Services Provision
No full textInternational audienceThousands of drone operations are expected over urban areas in different countries, as drones bring economic and societal benefits. However, it raises problems regarding unmanned traffic management, including safety, regulatory, security, automatization, communication, and scalability aspects. How can we provide decentralized services for drone traffic management that are compliant with the regulatory framework? We identified some requirements from the European U-space regulation and applied the Systems Development Methodology. We devised a permissioned blockchain-based architecture, Services as smart contracts, and a simple consensus mechanism named Appointed-by-Authority as conceptual contributions. The practical one is a working software named U-spaceChain. It is a proof-of-concept of a blockchain in which smart contracts provide Flight Authorization, Network Identification, Traffic Information, Conformance Monitoring, Geo Awareness, Weather Information, and Common Information services. It is compliant with regulations, secure by design, can support the development of new services, and the concepts can be reused in other domains. We also designed enablers that allow testing this proof-of-concept by creation and then simulation of drone traffic. U-spaceChain may be a reference for the research and application of blockchain to the drone traffic management domain
C/N0 degradation in presence of chirp interference: statistical, real and estimated C/N0
No full textInternational audienceTo characterize the impact of a RFI signal on the effective carrier-to-noise power density ratio, C/N0, of a GNSS receiver is very important for civil aviation standardization procedures in order to define Radio Frequency Interference (RFI)/jamming robustness test for two reasons. First, the prediction of the effective C/N0 is fundamental to predict the minimum performance attainable by an airborne GNSS receiver and to adjust the tests accordingly. Second, the receiver’s estimation of the effective C/N0 can allow the detection of the jamming presence and thus can help the receiver to adapt to the RFI situation. This problematic is analyzed with the introduction of three C/N0 definitions, statistical C/N0 which is the statistical prediction of the effective C/N0, real C/N0 which is the true effective C/N0 faced by the receiver and estimated C/N0 which is the value provided by a C/N0 estimator. Three conditions of validity are given to establish a relationship of equality between the three terms: ergodicity, centered RFI contribution at the correlator output and C/N0 estimator characteristics. To evaluate this last condition, Narrow-Wideband Power Ratio (NWPR), Signal-to-Noise Variance (SNV), Beaulieu and Moments Methods (MM) estimators are inspected and their expected mean value in presence of a generic RFI is theoretically derived. Finally, a full analysis is conducted for a RFI chirp signal showing that not all chirp signals are able to allow a statistical prediction of its effective C/N0 (condition of validity 1) and that NWPR and SNV are the more robust estimators (condition of validity 3) against this type of RFI