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This paper presents an outdoor-to-aircraft measurement campaign conducted inside a long range Airbus A340-300 aircraft. The attenuation induced by the hull of the aircraft for various operational frequencies is determined and these results are utilized to perform interference studies and assess whether the aircraft mobile terminal interferes to the ground base station and the opposite. [ABSTRACT FROM AUTHOR]

Motivated by spectral separation, guidance and control systems of interceptors are traditionally designed separately. However, interception of highly maneuverable targets and increased interception accuracy requirements lead to intense maneuvering during the last phase of the engagement, thus violating the spectral separation assumption of the conventional two-loop design. This has boosted the interest in integrated guidance-control designs that demonstrate superior interception accuracies by accounting for the coupling between the kinematics and dynamics of the problem. One of the approaches used for the integrated design is the sliding mode control (SMC) methodology. The results presented so far assumed full state information. We examine the effect of estimation on the performance of the integrated sliding mode controller design. In particular, a sliding mode observer/differentiator (SMOD) is used to estimate the target states. Through an intensive numerical study it is shown that the integrated guidance-control approach has a clear advantage over a conventional separated two-loop design. This advantage is attributed to the robustness of the integrated sliding mode controller design that better deals with the estimation errors and measurements noises. [ABSTRACT FROM AUTHOR]

Robust and early detection of oscillatory failures in the electrical flight control system of an aircraft is a crucial issue. Oscillatory failures, if not detected and passivated in time, can lead to strong interactions with loads and aeroelasticity and may potentially lead to structural damages. A nonlinear observer-based solution to detect such failures with small amplitude at a very early stage is presented. The stability and convergence proofs are given and experimental results with real A380 flight data are presented. [ABSTRACT FROM AUTHOR]

We describe a novel technique for vision-based UAV (unmanned aerial vehicle) navigation. In this technique, the navigation (position estimation) problem is formulated as a tracking problem and solved by a particle filter. The state and observation models of the particle filter are established based on a stereo analysis of the image sequence generated by the UAV's video camera in connection with a DEM (digital elevation map) of the area of the flight, which helps to control estimation error accumulation. The efficacy of this technique is demonstrated by simulation results. [ABSTRACT FROM AUTHOR]

Highly-dynamic wireless environments present unique challenges to end-to-end communication networks, caused by the time-varying connectivity of high-velocity nodes combined with the unreliability of the wireless communication channel. Such conditions are found in a variety of networks, including those used for tactical communications and aeronautical telemetry. Addressing these challenges requires the design of new protocols and mechanisms specific to this environment. We present a new domain-specific architecture and protocol suite, including cross-layer optimizations between the physical, MAC, network, and transport layers. This provides selectable reliability for multiple applications within highly mobile tactical airborne networks. Our contributions for this environment include the transmission control protocol (TCP)-friendly transport protocol, AeroTP; the IP-compatible network layer, AeroNP; and the geolocation aware routing protocol AeroRP. Through simulations we show significant performance improvement over the traditional TCP/IP/MANET protocol stack. [ABSTRACT FROM AUTHOR]

One current method of aircraft flightpath generation employs multi-segmented straight trajectories with each consecutive pair of segments filleted with arcs of constant radius. A difficulty of infeasibility immediately arises. In order for an aircraft to make the transition from a straight to a curved path segment (or vice versa) there is a physical requirement for a step acceleration, implying an infinite jerk. Clothoid curves provide a solution and have been investigated to fillet the consecutive segments. However, in this case, the mathematical definition of the clothoid is in terms of an integral that precludes closed-form solutions for critical guidance parameters. The attractiveness of the clothoid is to solve the physical infeasibility problem, however the mathematical intractability inherent in the approach has attracted limited attention despite being recognised as a major concern through early experiments. A method is presented here where double clothoid curves are used to fillet consecutive segments. This work goes beyond present practice to provide closed form solutions by using the hyperbola as a clothoid facsimile. Acceleration constraints have been enforced, both accumulative and maximum, and both the reference bank angle and bank angle rate have been expressed analytically in closed-form in terms of hyperbolic parameters. The solution can be optimised in terms of accumulative acceleration and path length, whilst simultaneously enforcing maximum acceleration constraints. This method of trajectory generation is attractive for implementation with air traffic management separation assurance, tunnel-in-the-sky, and other proposed cockpit display systems. [ABSTRACT FROM AUTHOR]

In this paper, a methodology is developed to evaluate differential carrier phase navigation architectures subject to reference receiver faults. Carrier phase measurements can be used to provide high accuracy estimates of a user's position. But in applications that involve safety-of-life, such as in precision approach for autonomous shipboard landing, integrity also plays a critical role. One source of integrity risk is the potential for GPS reference receiver failure. Integrity risk in these situations is typically mitigated by equipping the reference station with redundant receivers. However, various approaches to utilize redundant carrier phase measurements from multiple reference receivers are possible. In this paper, we describe two new methods: an averaging approach where different position solutions are averaged in the position domain, and a coupled estimation approach where the measurements from all reference receivers are coupled in the range domain and used to estimate a unified position solution. Furthermore, we investigate the impact of using these methods on accuracy and integrity from several perspectives, including availability performance, cycle resolution capabilities, implementation complexity, and computational efficiency. [ABSTRACT FROM AUTHOR]

Herein, the avionics system design of a mini Vertical Take-Off And Landing (VTOL) capable Unmanned Aerial Vehicle (UAV), namely a Quadrotor, will be described. The Turkish Air Force Academy personnel together with a team of cadets have been working on the design and development of an autonomous Quadrotor vehicle for educational purposes. The main emphasis was to study the flight dynamics of such a vehicle but the development of on-board electronics that consists of a sensor payload, embedded computer, and other hardware, along with the embedded software was such a critical work package under the project that required special emphasis and an innovative approach. A new avionic architecture that is derived from the rationale of Integrated Modular Avionics (IMA) architecture of today's larger platforms is proposed and currently being implemented within the framework of our project. The advantages of this approach for the development of mini/micro UAVs along with the academic education of our cadets will be discussed. [ABSTRACT FROM PUBLISHER]

Looking back on the first seven Impact columns for IEEE Software, the editors propose a new metric called software mileage, defined as the number of new customers per year per line of code. [ABSTRACT FROM PUBLISHER]

Up to now, combat aircrafts are titted with Fire Control Radar (FCR), Electronic Warfare Systems (EWS), and some radio links. Each of these systems Is dedicated to a particular task and cooperation is reduced to a minimal exchange of information between them, so far. Major system performance enhancements are to be expected from close cooperation to other sensors. The future cooperations can be ordered in four stages: the first three stages lead progressively to a multi-function sensor. The last is the deployment, on a given platform, of compact multi-function sensors on a network basis. Another area of cooperation is the realization of RF functions currently provided by other devices using other antennas. A typical example is the implementation of data links using radar or the EWS. [ABSTRACT FROM PUBLISHER]

The Smart Skies project is an ambitious and world-leading research endeavor exploring the development of key enabling technologies, which support the efficient utilization of airspace by manned and unmanned airspace users. This provides a programmatic description of the research and development of: an automated separation management system; a mobile aircraft tracking system; and aircraft-based sense-and-ad technologies. A summary of the results from a series of real-world flight testing campaigns is also presented. [ABSTRACT FROM PUBLISHER]

The European organization for the Safety of Air Navigation is developing and maintaining BADA for use in trajectory simulation within the field of Air Traffic Management (ATM). There has been continuous research on using BADA for the estimation of fuel consumption and aviation global emission. In contrast, little attention has been paid to utilize BADA as an on-board navigation support system. In this research, we propose a framework using BADA's operation data to check if an aircraft is operating within a recommended speed, rate of climb or descent (ROCD), or fuel flow. Various simulated flight scenarios were introduced in a controlled deterministic environment, and the results accurately verified the concept of operation. [ABSTRACT FROM PUBLISHER]

This describes the range of aircraft location vertical finders to determine pitch and roll angles. The devices mentioned reflect the main stages of the attitude control system development throughout history at the Control Device Department of Tula State University, ranging from classical platform systems to micromechanical and pyrometer strap-down attitude reference systems. A multi-functional attitude gyroscope based on two two-degrees-of-freedom gyros driven by electric gyro motors has been discussed as a classical platform attitude gyroscope. Strap-down vertical references are represented by system samples based on micromechanical inertial sensors and pyrometer detectors. This provides the specifications of vertical references concerned and performs the comparative analysis thereof. It also shows the advantages and disadvantages of each of these systems. [ABSTRACT FROM PUBLISHER]