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Ukrainian navigational aids network has a long history of deployment and development. Currently, navigational aids network includes ground equipment of Distance Measuring Equipment (DME), Very high-frequency Omni-directional Ranging (VOR), and Non-Directional Beacons (NDB). In our research, we would like to provide an overall study of navigational aids network configuration to specify the impact of particular ground station on the service provided. Common models of navigational aids are considered to estimate navigational aids availability and efficient pair forming in case of positioning by DME/DME and VOR/VOR. An area of correspondence to RNAV requirements is used as a criterion to estimate the impact of each navigational aid on overall network performance. Also, the navigational aids network is represented in the form of a weighted graph to estimate characteristics of centrality and betweenness for ranging network nodes. Configuration of Ukrainian navigational aids network is studied as an example. Obtained results are useful for a better understanding of navigational aids network configuration.

Algorithms of positioning by navigational aids are widely used as an alternative to Global Navigation Satellite System on-board of large airplanes. Distance measuring equipment is a commonly used navigational aid for alternative positioning by a pair of measured ranges. Errors of range measuring are directly connected with airplane localization in airspace and have primary influence in airplane trajectory maintaining as well as ensuring the required level of air traffic safety. The impact of errors of on-board positioning system into aviation safety is represented in the paper. A mid-air collision category of aviation safety is assessed based on risk of airplane unintentional deviation from planned location due to influence of on-board positioning system errors. Represented approach is grounded on location of a bivariate probability density function at each airspace user location and estimation of a probability of getting two airspace users within the same safety region. Airplanes separation minimums are used as size of the safety region. Numerical demonstration is provided by live air traffic data shared by Automatic Dependent Surveillance-Broadcast message and received by Software Defined Radio within a part of Ukrainian airspace volume. Risks of mid-air collisions for each pair of airspace users are estimated.

PBN Vertical Navigation (VNAV) flight procedure refers to 3D RNP approach with vertical guidance, while Lateral Navigation (LNAV) refers to 2D RNP approach without vertical guidance. According to the relevant requirements of RNAV (GPS) approach procedures in ICAO PANS-OPS and USA FAA TERPS criteria for PBN instrumentation procedure design (8260.58A chg1 and 2), the impact of the two specifications on the key design parameters and vertical path angle of VNAV procedures, especially the horizontal protection area and vertical obstacle clearance margin in OAS surface(ICAO) and OCS surface(FAA) is discussed in this paper. Taking runway 06 of an airport as a case analysis, this paper designs VNAV procedures of two specifications when RNP values are 1 and 0.3(only the final segment), evaluates and determines key obstacles, and gives suggestions for PBN in Barometric Vertical Navigation specification.

Instrument flight procedures (IFPs) are a cornerstone of the National Airspace System (NAS) and provide paths and instructions for aircraft to safely operate in restricted visibility and in congested airspace. Design of IFPs that adhere to the criteria developed by the FAA to ensure safe flight can be a tedious, iterative task. This is particularly true in areas with complex obstacle/terrain environments. Previous work was conducted by MITRE to develop criteria modules (CM) capable of analyzing a procedure design’s compliance with FAA criteria. In this paper, these engines are leveraged to evaluate batches of candidate procedures. To ensure convergence to an acceptable solution in a reasonable period, a modified depth-first search algorithm was designed to mimic the general design flow used by human procedure designers. By combining this algorithm with the capability of the CMs and a batch cluster for analyzing multiple procedures in parallel, it is shown that procedures can be built in tightly constrained situations by adapting common algorithms to the specific requirements of IFP design.

Most of the conventional procedures could be coded effectively into the navigation database based upon the ARINC specification 424. But in some special cases, it’s hard to code as the procedure’s designer does not comply with the ARINC specification 424 when they design the conventional procedures. This paper will analyze some of these special cases from the practical experience, and will also provide the solutions to these cases after the analysis.

The estimation of air traffic safety is based on determining the probabilities of negative events that may occur over a specified period of time. The concept of flight safety is based on the estimation of the risks of adverse events that may occur during a flight, compared with a certain level of acceptable risk. A significant component of the risk of aircraft deviation from the planned trajectory and the risk of aircraft collisions is risk of the positioning system lock. In the article under the risk of the positioning system lock, we consider the probability of the system's inability to determine the coordinates of its location within the limits of required performance under area navigation working at the point of aircraft location. The risk assessment model is based on estimated Total System Error (TSE) values for standby navigation systems by pairs of navigational aids: DME/DME, VOR/DME, and VOR/VOR. Performance estimation of probability indicator allows moving from the metric value of TSE to the percentage level of navigation lock risk, which allows to get more adequate reflection of navigation characteristics in assessing the safety of aviation in a particular airspace volume. The risk of navigation lock by navigational aids has been analysis for Ukrainian airspace as an example.

An issue of on-board performance monitoring and alerting of the aircraft navigation system compliance with the required safety level associated with area navigation specifications is considered. It is proposed to use a probabilistic approach based on Bayesian criteria for monitoring characteristics of the navigation system in the horizontal plane and alarming of area navigation mode. Usage of probabilistic approach allows to recognize navigation system compliance with required navigation performance specification at the lowest risk. NSE value is used as a key parameter for classification.

Performance estimation of aircraft positioning system by navigational aids in three-dimensional space is proposed in the paper. Positioning system by pairs of Distance Measuring Equipment (DME/DME), Very high frequency Omni-directional Range (VOR/VOR) and their fusion (VOR/DME) is considered as stand-by approach on board of aircraft. Performance of positioning system depends on geometry of navigational aids location in space and technical characteristics of ground-based equipment. System performance analysis in tree-dimensional space gives possibility to estimate characteristics variation with altitude. Proposed approach divides investigated airspace into set of elementary cells for statistical simulation with iterative approach of performance characteristics estimation. Obtained performance levels are compared with area navigation specification requirements to detect gaps in service. Performance analysis of aircraft positioning systems in three-dimensional space by navigational aids was done for Ukrainian airspace.

Capability of aircraft tracking by communication data in Airborne Collision and Avoidance System (ACAS) is discussed in the paper. ACAS surveillance functionalities provide precise range measurements for each user of airspace. Proposed approach considers fusion of surveillance data together with Automatic Depended Surveillance Broadcast communication messages to construct a navigation equation and find aircraft location as a solution. Questions of positioning accuracy by ACAS data are considered in more detail. Matrix equation for mean squared deviation estimation for positioning in horizontal plane that takes into account uncertainties ellipsis of airspace user’s location is proposed.

Aircraft passive positioning by receiving radio signals of Distance Measuring Equipment (DME) together with processing data from Automatic Dependent Surveillance Broadcast (ADS-B) about surrounding air traffic is represented in paper. Interrogation messages of other aircraft are used with ground DME network reply messages to calculate Time Difference of Arrival and for further passive aircraft coordinates estimation by hyperbolic navigation method. Communication message transmission by ADS-B is considered as a source of DME interrogators location for relative navigation approach. Accuracy assessment of hyperbolic positioning takes into account uncertainty areas of DME interrogators location. Accuracy analysis is performed with computer-based simulation with live air traffic data.

26th IEEE Signal Processing and Communications Applications Conference (2018 : Izmir, Turkey), As an alternative to Global Positioning System (GPS) position calculation can be achieved using Distance Measuring Equipments (DME). DME calculates and outputs a slant range using the total time from the aircraft interrogation to ground station reply. It is necessary to have two DMEs to calculate the position from the slant range data. In this paper, the algorithms are explained that achieve to estimate instantaneous latitude, longitude, altitude and velocity of an aircraft using the slant range data of two DMEs and the altitude data of an altimeter. The algorithms are based on the least squares method and Kalman filter. It is achieved to estimate position with the least squares method. Moreover, with the proposed model for the Kalman filter, the position and velocity estimation is achieved. The algorithms were tested on the previously recorded real aircraft data and their results were within the aviation standards. Furthermore, a plugin was implemented for X-plane flight simulator and the algorithms were capable of estimating instantaneous position and velocity successfully. © 2018 IEEE.

The development of multi-constellation, multi-frequency GNSS is ongoing, with the aim to enable a robust and reliable navigation and approach service to airspace users. While this will greatly reduce vulnerability to space weather, unintentional interference and constellation weakness, some residual vulnerabilities will remain. In the current, predominantly GPS L1 GNSS environment, aviation has accepted that alternate positioning, navigation and timing capabilities based on terrestrial systems remain necessary. These reversionary area navigation capabilities are based primarily on DME/DME, while still providing some residual VOR/DME services. However, this reversionary capability has not been demonstrated to support the stringent RNP requirements that GNSS can support. Also, DME is criticized as being spectrum inefficient, and aviation-internal and aviation-external pressures to share the DME band with other services are increasing significantly. A key question for the future evolution of Communication, Navigation and Surveillance systems is what type of a reversionary capability will be needed in the future (terrestrial or space based), and what performance levels it needs to provide. To answer this question, supported by specific technology options, a project under the SESAR Horizon 2020 Framework (PJ14-03-04) is working on this topic under the title “Alternative Positioning, Navigation and Timing, A-PNT”. A-PNT is a complex, multi-disciplinary topic, with technical and operational aspects going across the CNS domains, and spectrum concerns being an underlying driver. The research activities in PJ14-03-04 are covering a selected set of potential technical solutions: take full advantage of the actual DME performance, DME enhancements (ensuring compatibility with legacy systems), LDACS NAV function and eLORAN. This paper will focus the discussion on the performance levels achievable by each of these technologies and their major advantages and drawbacks. The concept of a modular approach will be introduced as well (which allows the computation of a position solution with integrity based on inputs from various types of sensors). The paper includes contributions from the following SESAR partners: EUROCONTROL, DLR, Thales Avionics, Thales Air Systems and Honeywell Aerospace.

▪ Wide implementation of PBN applications in all phases of flight ▪ FRA based on RNAV 5 in en route airspace ▪ SIDs/STARs predicated on RNP 1 with RF legs in high density TMAs ▪ SIDs/STARs predicated on RNAV 1 in additional TMAs ▪ Low altitude helicopter routes predicated on RNP 0.3 ▪ RNP/APCH (LNAV/VNAV and/or LPV minima) at all instrument RWY ends ▪ GNSS is the nominal sensor for all PBN operations (required for RNP) ▪ DF-MC GNSS on the horizon ▪ Is there still a need for terrestrial backup?

Various indoor navigation methods have been developed recently, but digitalized data of indoor map is not always available. Therefore, an indoor navigation framework using an image of information board has been proposed. In this method, the process to extract map regions from the image of an information board is necessary to be done by hands beforehand, and the process to estimate passageway regions is important because its information is used in map matching. However, the method of passageway discrimination is very heuristic, which is intended for a specific type of floor maps. Therefore, in this paper, we propose a semi-automatic method to extract map regions from the image of information board with simple user's operation. We use GrabCut method and Snakes method for the extraction method. In GrabCut method, we detect closed regions to prevent the degradation of accuracy when conducting GrabCut to the downsizing image. The proposed method can extract a map region with few deficits in short calculation time. In addition, we propose a machine learning based method to classify passageway regions and other regions from a segment image. We confirmed that the proposed methods are effective and promising by experiments.

The trend in development of flight navigation and currently extended use of area navigation in standard departures enables us to direct the noise produced by air traffic at and above rarely populated areas. The construction of new standard departure paths with RNAV specification does not depend only on the layout of land radio-navigation stations and beacons, which gives the designers more freedom of choice. The paper analyses the standard departure path in Birmingham which leads over the town of Balsall Common where the noise has a negative effect on the local population. The aim of the authors is to redesign the flight path, more precisely part of the path, so as to deflect the dense concentration of departing aircraft from the densely populated area to northern parts of the city. Using a simplified model of a section of departure path, the authors could simulate the scatter of aircraft and their concentration on that path. The validity of practical usage has been successfully confirmed upon the verification of the model.

Flight crews and air traffic controllers have reported many safety concerns regarding area navigation standard terminal arrival routes (RNAV STARs). Specifically, optimized profile descents (OPDs). However, our information sources to quantify these issues are limited to subjective reporting and time-consuming case-by-case investigations. This work is a preliminary study into the objective performance of instrument procedures and provides a framework to track procedural concepts and assess design specifications. We created a tool and analysis methods for gauging aircraft adherence as it relates to RNAV STARs. This information is vital for comprehensive understanding of how our air traffic behaves. In this study, we mined the performance of 24 major US airports over the preceding three years. Overlaying 4D radar track data onto RNAV STAR routes provided a comparison between aircraft flight paths and the waypoint positions and altitude restrictions. NASA Ames Supercomputing resources were utilized to perform the data mining and processing. We assessed STARs by lateral transition path (full-lateral), vertical restrictions (full-lateral/full-vertical), and skipped waypoints (skips). In addition, we graphed frequencies of aircraft altitudes relative to the altitude restrictions. Full-lateral adherence was always greater than Full-lateral/full-vertical, as it is a subset, but the difference between the rates was not consistent. Full-lateral/full-vertical adherence medians of the 2016 procedures ranged from 0% in KDEN (Denver) to 21% in KMEM (Memphis). Waypoint skips ranged from 0% to nearly 100% for specific waypoints. Altitudes restrictions were sometimes missed by systematic amounts in 1,000 ft. increments from the restriction, creating multi-modal distributions. Other times, altitude misses looked to be more normally distributed around the restriction. This tool may aid in providing acceptability metrics as well as risk assessment information.

A low accuracy of positioning using Global Navigation Satellite System (GNSS) are not meet geodetic requirements for direct images georeferencing for Unmanned Aerial Vehicle (UAV) photogrammetry. A majority of UAVs are equipped with a monocular or stereo non-metric cameras for either visual data gathering or live video feed for operator. A cheap positioning techniques used on board commercial UAVs are not that precise as geodetic community requires. Moreover, a traditional satellite navigation suffers from a multipath Global Positioning System (GPS) signal in an industrial environment and cities or during operation in poor GPS space segment geometry or in indoor environment. In that cases, the UAV position can be enhanced by a visual navigation method. The paper presents a results of implementation of recently developed robust simultaneous localization and mapping method for a low cost hexacopter platforms navigation system augmentation, in order to support a precise and robust direct images georeferencing.

In order to guarantee availability and continuity in Alternative Position Navigation and Timing (APNT), inertial systems are considered to coast the navigation position in case of navaids coverage gaps. For instance, DME/DME/Inertial (DDI) is currently considered for RNAV 1.0 operations. However, in order to support future RNP operations, the accuracy is not the only requirement to be fulfilled and other safety checks and integrity measures must be provided. This work analyses different fault detection mechanism for a multi-DME/Inertial system based on the innovation sequence of a Kalman filter. We aim to detect both single bias and ramp type fault profiles using snapshot and sequential test statistics. We evaluate the algorithms using our simulation framework based on real DME locations and realistic sensor error models.

The goal of the integration of Unmanned Aircraft Systems (UAS) in the National Airspace System (NAS) is to achieve “file-and-fly” access to all classes of airspace. This means the UAS will fly without limitations or waivers in airspace shared with other manned and unmanned aircraft. In the case of large UAS operating in a similar manner to transport category aircraft in terminal, en-route and oceanic/remote environments, this includes the ability to perform area navigation.

The FAA's recently announced 2016 Performance Based Navigation (PBN) National Airspace System (NAS) Navigation Strategy states that it will retain and expand Distance Measuring Equipment (DME/N) infrastructure to help ensure continued Area Navigation (RNAV) service during Global Navigation Satellite Systems (GNSS) outages. The targeted navigation performance using DME/DME in this strategy is RNAV 2.0 in the En Route Domain without requiring Inertial Reference Unit (IRU) and RNAV 1.0 in some large Terminal Areas. It is expected that DME will still play an important role as an alternative RNAV navigation source beyond 2030. It is, therefore, desirable to determine if the performance of DME can be improved to enable PBN of higher navigation accuracy to better meet future air traffic needs. This paper investigates the benefit of a newly developed DME/N pulse using Genetic Algorithms (GA) that can provide much higher ranging accuracy than the conventional Gaussian or Smoothed Concave Polygon (SCP) pulse while meeting the pulse shape requirements in current DME specifications. The primary benefit analysis will compare the achievable DME/DME positioning accuracy with a current DME ground network and compare the DME ground network requirements needed to meet RNAV 0.3 and 92.6 m surveillance positioning accuracy using the conventional Gaussian and the GA-based pulses in selected areas in Conterminous US (CONUS) NAS.

Localization technique is a key technology for vehicular navigation and control. The use of satellite navigation is deemed essential. Yet, satellite-based navigation system is subject to multipath effect and signal blockages in urban area. To enhance the overall navigation capability, odometry techniques have been used as dead-reckoning devices to augment satellite navigation. To account the issues of sensor selection and sensor fault detection in an integrated vehicle navigation, the paper compares three odometry techniques based on monocular camera, laser scanner, and inertial sensor, respectively. The assessment is based on real data at a representative scenario.

In the Unmanned Air Vehicle (UAV) navigation the main challenge is estimating and maintaining the accurate values of UAVs position and orientation. The onboard Inertial Measurement Unit (IMU) provide the measurements but it is mainly affected from the accumulated error due to drift in measurements. Traditionally the Global Position System (GPS) measurements of vehicles position data can be fused with IMU measurements to compensate the accumulated error, But the GPS signals is not available everywhere and it will be degraded or fully not available in hostile areas, building structures and water bodies. Researchers already evolved methods to handle the UAV navigation in GPS denied environment by using Vision based navigation like Visual Odometry (VO) and Simultaneous Localisation and Mapping (SLAM). In this survey paper we attempted to understand the existing research towards vision based navigation and finally proposed a Modular Multi-Sensor Data Fusion technique for UAV navigation in the GPS denied environment.

The method of cooperative navigation is proposed in this study to solve the terrible results of the indoor pedestrian navigation due to GPS information unavailable and the serious divergence of inertial navigation. To improve the pedestrian navigation accuracy, the paper designs a cooperative pedestrian navigation system which is based on the distance restraint between the pedestrians and applies the information filter to get the navigation result. The experiment is designed to prove the effectiveness of cooperative pedestrian navigation using the MIMU and UWB measurement equipment. The final results show that the interactive fusion of navigation information for each pedestrian is achieved and the divergence of the navigation results is restrained.

Modern warships are often equipped with small airstrips that are dedicated to helicopters or other vertical take-off and landing (VTOL) units. Therefore, this type of vessels should have navigation systems that provide process automation of take-off and landing for these flying units. Currently, the Global Navigation Satellite Systems (GNSS) is used for this purpose. The accuracy of the positioning based on GNSS may prove to be insufficient during automatic landing approach of unmanned aerial vehicles. In the military operation area, GNSS signals may be jamming or spoofing. Additionally, it may be limiting visibility related to smoke screens or natural factors, e.g. fog. Thus, there is a need for a dedicated radio navigation systems. This paper presents a concept of the local navigation system (LNS) that based on the signal Doppler frequency (SDF) location method. LNS allows positioning of the landing VTOL with high precision. The accuracy of VTOL positioning in LNS is shown on the basis of two scenarios of simulation studies.

The use of autonomous navigation in Unmanned Aerial Vehicles is growing every day, in many areas, due to the low cost of its deployment and also does not require a pilot in a ground station. The most applied technique for autonomous navigation of Unmanned Aerial Vehicles is the joint use of Global Navigation Satellite System with Inertial Navigation System, an alternative for this technique is the autonomous navigation through image processing. To perform the autonomous navigation of Unmanned Aerial Vehicles through image processing are used usually images that has landmarks in the ground to guide the trajectory. But, still is a challenge perform the autonomous navigation of Unmanned Aerial Vehicles through image processing, without Global Navigation Satellite System combined with Inertial Navigation System, over regions without landmarks, such as the ocean. Therefore, this research presents a methodology to perform the estimation of Unmanned Aerial Vehicles position in LiDAR images to allow that it performs the autonomous navigation over the ocean.

An Electronic Navigational Chart (ENC) is a standardized database that can be used with an Electronic Chart Display & Information System (ECDIS) for applications such as navigation warning, efficient route planning for ship navigation, etc. An ENC contains all the required information for ship navigation. Route planning on the ENC is done with a consideration of the depth area, distance with isolated danger area, structures requiring navigation, wrecks, etc. Because route planning has to be done in consideration of these factors, sometimes a route will have a longer distance than the straight line distance. This causes much loss of time and fuel. In order to reduce the loss of time and fuel, it is necessary to have a wide navigation area. The first item of consideration, the depth area, has a decisive effect on route planning. However, the depth area consists of a large interval of about 5 to 10 meters and this interval can cause a gap of several kilometers on the horizontal distance. This means that the navigation area is (narrower than the optimized navigation) not optimal on narrow waterways, has a low slope surplane, and in some cases there are problems with under water topography. This paper suggests a method to obtain an optimized navigation area using water depth information, which has denser depth information than the depth area in the ENC and can be used to verify the method of ECDIS route planning using depth area and water depth information. Water depth in the ENC has more density resolution depth information than does the depth area and is extracted in a triangular shape; no lower sounding depth than the selected depth is allowed within the extracted sounding depth. Considering this characteristic for triangulation, underwater topography formed by triangulation based on water depth applying the Delaunay Algorithm can be used to compare a triangle edge's depth information and the safety depth of a ship in order to classify the triangular safety area. Implementation was performed to compare two ship route plan modules with a consideration of mariner setting on ECDIS. Comparison of the two route plans, which is focused on the route length and the entire expected amount of time spent from the start waypoint to the end waypoint, was used for the verification of the route planning efficiency.

Many advanced navigation devices have been installed on board small vessel to ensure their safety by avoiding marine disasters. However, the number of marine disasters involving small vessels has not declined significantly. Causes for this lack of reduction are human error, crew members inexperienced in ship maneuvering, etc. Therefore, a new maneuvering support system is needed. This paper deals with the construction of a maneuvering support system. In road traffic, a car navigation system has been generally used and has been effective in reducing road accidents. We constructed a sea navigation system named for the car navigation system. The results of field experiments and a questionnaire have confirmed the effectiveness of this system.

Navigation enhanced information (NEI) is very important to improve the positioning and navigation performance of GNSS receivers, and the current available NEI mainly come from static station observation data, which don't has enough credibility and area attribute. In this paper, an parallel area navigation enhanced information (ANEI) extraction algorithm based on massive historical GNSS data and MapReduce is proposed, to get the ANEI which is much more effective than traditional NEI, and the high efficiency of the algorithm is guaranteed by using the Hadoop parallel programming model MapReduce. The principle of the algorithm is as follows: a large number of historical GNSS Intermediate Frequency data is divided into blocks to be acquired and tracked parallel to get massive multi satellite system pseudorange and navigation message (MPD), then, the massive MPD are weighted and fused parallel by using variance component estimation to get the NEI which will be corresponded to the corresponding location coordinate, completing the parallel extraction of ANEI. Experimental results show that the positioning error of GNSS receivers is reduced about 18.24% by using ANEI instead of traditional NEI, and the execution time of the algorithm is reduced about 46.72% by using MapReduce, so the algorithm proposed in this paper is more reliable and effective.

We present a new mapping and navigation system based on human-recognizable landmarks with highly compact representations. Road segments, intersections and salient structures such as houses and trees are detected using vision and LiDAR data. The landmarks are entered in a sparse metrictopological map that is used for navigation. In contrast to traditional SLAM approaches, however, we only store the information required to navigate along the path of the robot that built the map. Due to the sparseness of the data, it can easily be transmitted to other robots via a low-bandwidth radio connection (9600 bit/s), allowing the receivers to reconstruct the map, localize themselves in it and follow the path recorded by the sender. All of this is done without the help of global navigation satellite systems such as GPS. The algorithms were tested and evaluated in practical experiments with our autonomous cars MuCAR-3 and MuCAR-4.

As the United States (U.S.) moves toward the various phases of Next Generation Air Transportation System (NextGen), there will be more emphasis on control of aircraft using time as well as the traditional speed control. With this in mind, Radio Technical Commission for Aeronautics (RTCA) was directed by Federal Aviation Administration (FAA) in 2012 to revisit the Minimum Aviation System Performance Standards (MASPS): Required Navigation Performance (RNP) for Area Navigation (RNAV), DO-236B [1], to update the requirements for RNP RNAV systems based on lessons learned from implementing Performance Based Navigation (PBN). The committee was also asked to consider a forward look/refinement of the time-based requirements for systems. The RNP RNAV system performance standard DO-236C [2] Change 1 [3] amended existing standards from DO-236B by expanding the minimum requirement for system computed Estimated Time of Arrival (ETA) in a Flight Management System (FMS). The new minimum functional requirement is that the ETA must be available for each fix in a flight plan; the previous minimum only required ETA at the “go to” fix. In an important addition, DO-236C Change 1 sets a minimum performance requirement on ETAs at all planned (future) fixes in the onboard flight profile. Thus the standard has been expanded both in the functional and the performance requirements for ETA in an RNP RNAV system.

The goal of the paper is to present a new method developed to provide a surveillance of the air space. It detects and finally determines location of air vehicles which are currently using RNAV DME-DME method to measure their own positions. By processing signals between an air vehicle and ground based DME beacon the observer is able to determine current distance between an aircraft and the beacon. This effectively changes the role of the DME from a navigation aid (an aircraft determining its own position) to a surveillance aid (an observer determining the position of a DME-equipped aircraft). There is no need for other systems or signals, and the detection and localization of the target can be done from a single point (the observer).

Precise navigation of mobile robots in unknown areas is common problematic in many research papers. For navigation in outdoor areas Global Navigation Satellite System (GNSS) is typically used. For better position estimation in Europe augmentation satellite system called European Geostationary Navigation Overlay Service (EGNOS) it is used. In US it is similar system called Wide Area Augmentation System (WAAS). These systems are not usable in indoor areas because the weak of signal and the low position accuracy. For indoor areas, it is necessary to use an alternative navigation system - independent on satellite navigation. In our research we are focusing on visual odometry using a monocular camera. Advanced image processing methods on camera images to achieved accurate visual odometry are applied.

UAV's (Unmanned Aerial Vehicle) in general fly in open space, far from any obstacles and relay on external beacons, mainly GPS (Global Positioning System) to localize them and navigate. This approach precludes them from evolving autonomously at low altitudes, in cluttered and confined environments. The autonomous flight in these cluttered environments like houses or urban canyons requires high maneuverability, fast mapping from sensors to actuators and very limited overall system weight. The flying animals are well capable of coping with such situations and so a much similar navigation method is to be adopted. The optical flow navigation will be best suited for these situations. Optical flow is a technique which is used to determine the motion of the surfaces of the objects in relation to the observer. The use of hardware and power consumption in the optical flow navigation is very much less when compared to other navigational aids and thus it is being developed for micro air vehicles enabling to fly in cluttered environments with high maneuverability fast mapping and very little overall system weight.

This paper has presented an implementation of visual based non-GNSS navigation method for small VTOL (Vertically Taking-off and Landing) UAV (Unmanned Aerial Vehicle). A novel method of constructing landmarks is described in detail. It uses a pair of landmarks instead of the general landmark which usually is a single geometry or coding image. The paired-landmark method inherits general landmark methods' advantages of low-cost, high-efficiency and the ability of absolute positioning. And it also solves the problem of requiring too much different characteristic landmarks when handling large area navigation. The paired-landmark method has been verified by a real parameter simulation environment. Real flight experiment is also carried out to test the effectiveness and performance of the paired-landmark navigation method. It can be concluded that, besides achieved the expected positioning precision, the proposed system also reduced the consumption of calculation and memory space.

Modern navigation complexes of unmanned aerial vehicles consist of many navigation systems: inertial navigation system, satellite navigation system, landmarks navigation system, terrain navigation system, etc. For high accuracy systems the use of neural networks further to the improvement of their quality.

Terrain-aided navigation is well known as an autonomous navigation method for aircrafts, missiles, underwater vehicles, and etc. The performance of iterative closest contour point (ICCP) algorithm is investigated in this paper deeply. The factors, including, the INS (inertial navigation system) precision, the map resolution, initial INS errors, the sonar accuracy, and the matching path length, which influence the matching errors, are studied for underwater vehicles. Simulations are accomplished to verify the performance of ICCP and some conclusions are summarized at the end.

In automatic navigation of mobile systems, first, they require providing a path network for robot/vehicle motion. Therefore, path planning is an important task of autonomous vehicle systems. To deal with the problem, this paper presents a method for constructing the shortest path, which support for vehicle auto-navigation in outdoor environments. The method using online road map images to estimate not only the shape of road network but also the directed road network, which could not be estimated by the use of only aerial/satellite images. The proposed method to solve this problem includes three stages. First, a raw network of path for motion is detected using the road map images. Second, the path network is converted to the Global coordinates, which provides a convenience for online auto-navigation task. Third, the shortest path for motion is estimated based on the A* algorithm. The experimental results demonstrate robustness and effectiveness of the method for path networks estimation under the large scene of outdoor environments.

Because PBN(RNAV/RNP) has been implemented in some Chinese routes step by step, and the routes in China are the crossing track mainly, so the stress of the collision risk should be put on the crossing track. The author analyzed deeply the collision risk of intersecting routes based on PBN in this paper. First,the collision risk model of crossing track is built, and the calculating methods are concluded, the influence to the collision risk by the flight separation minima and required navigation performance is analyzed, the minimum separation in given parameters is defined, which offer the theoretical basis for defining the reduced separation minima of the crossing tracks.

Like coastal navigation, which keeps distance from coast for knowing the ship's position, we consider features on an underwater Jacket structure for safer and more reliable autonomous navigation. The features would be useful information for autonomous navigation as well as localization of hovering-type AUVs (H-AUVs), which inspect an underwater Jacket structure. Based on the feature information, we define the concepts, “certainty” and “reliability”, and we explain a path planning algorithm, which modifies a variation of Bi-RRT algorithm to consider the reliability of paths much more. The simulation experimental results show that the explained path planning algorithm generates safer and more reliable path for autonomous navigation of an H-AUV.

The differences in performance of various manufacturers' Flight Management Systems (FMSs) and their associated Flight Management Computers (FMCs) have the potential for significant impact on the air traffic control system and as such need to be examined and reexamined. While Performance-Based Navigation (PBN), Area Navigation (RNAV) and Required Navigation Performance (RNP) procedures and routes are designed according to criteria contained in Federal Aviation Administration (FAA) orders, FMC manufacturers build their systems in accordance with Minimum Aviation System Performance Standards (MASPS) and Minimum Operational Performance Standards (MOPS) for area navigation systems, Technical Standard Orders (TSOs) and Advisory Circulars (ACs). With the exception of some minor differences, it has been shown in previous research on this subject that the resulting performance of the aircraft FMC will generally meet the procedure design requirements identified in the FAA criteria.

NASA has developed the Terminal Sequencing and Spacing (TSS) system, a suite of advanced arrival management technologies combining time-based scheduling and controller precision spacing tools. TSS is a ground-based controller automation tool that facilitates sequencing and merging arrivals that have both current standard ATC routes and terminal Performance-Based Navigation (PBN) routes, especially during highly congested demand periods. In collaboration with the FAA and MITRE's Center for Advanced Aviation System Development (CAASD), TSS system performance was evaluated in human-in-the-loop (HITL) simulations with currently active controllers as participants. Traffic scenarios had mixed Area Navigation (RNAV) and Required Navigation Performance (RNP) equipage, where the more advanced RNP-equipped aircraft had preferential treatment with a shorter approach option. Simulation results indicate the TSS system achieved benefits by enabling PBN, while maintaining high throughput rates-10% above baseline demand levels. Flight path predictability improved, where path deviation was reduced by 2 NM on average and variance in the downwind leg length was 75% less. Arrivals flew more fuel-efficient descents for longer, spending an average of 39 seconds less in step-down level altitude segments. Self-reported controller workload was reduced, with statistically significant differences at the p

Most aircraft, whether manned or unmanned, depend on the Global Positioning System (GPS) for navigation. However, GPS signals are susceptible to jamming and spoofing. A researcher recently demonstrated the use of spoofing to take control of a ship in the Mediterranean Sea. By feeding counterfeit signals to the ship, he was able to drive it far off course. All the time, the navigation system reported the vessel was moving calmly along its intended course. The same researcher also demonstrated the ability to spoof unmanned aerial vehicles (UAVs). The purpose of this paper is to demonstrate a navigation system that does not rely on GPS. The only sensor required is a digital camera. The system works by taking a photograph of the ground and georegistering it to a reference image or digital elevation model (DEM) with the GeoMI™ georegistration software. By transferring geospatial information from the DEM to the photo, the system calculates the position and orientation of the aircraft. The process is fast enough to perform in real time and suitable for use as a primary or backup navigation system for aircraft, UAVs, and cruise missiles. For nighttime navigation, the system could be extended to infrared or radar imagery. Experimental results show that navigation accuracies of 2 meters CE90 can be achieved.

In 2012, NASA and FAA jointly conducted a human-in-the-loop air traffic simulation to evaluate the utility of the Terminal Area Precision Scheduling and Spacing (TAPSS) system for supporting Performance-Based Navigation arrival operations during periods of congestion at a mid-sized airport. The TAPSS system is a trajectory-based strategic planning and tactical control tool that was developed to efficiently manage arrivals. For this study, the TAPSS system was enhanced to handle Required Navigation Performance arrivals. A baseline case, where none of the TAPSS system's advisories were provided, was run along with two different configurations of the TAPSS system with differing sets of controller advisory tools. The engineering data indicate that the TAPSS system has a potential to enable efficient Performance-Based Navigation arrival operations. The participating controllers found the TAPSS system's advisories useful. When controllers were given the full set of TAPSS advisory tools, 90% of Required Navigation Performance arrivals stayed on-path as compared to 87% in the baseline case, the average extra track distance of Area Navigation arrivals decreased by 36%, and the average number of controller voice communications decreased by 13%.

• Enhancements to TAPSS tools (slot markers and timelines) can facilitate the use of RNAV OPDs without sacrificing throughput in a challenging airspace • Enhancements to TMA regarding schedule coordination to converging runways can significantly increase throughput • Next steps: - Identifying necessary parameters for automating coordinated schedules to converging runways. - Evaluating the tools in less ideal environments -e.g., convective weather, one runway operations, etc.

International audience; The central dogma in molecular biology postulated that 'DNA makes RNA makes protein', however this dogma has been recently extended to integrate new biological activities involving small non- coding RNAs, called sRNAs. Accordingly, an increasing attention has been given to these molecules over the last decade and related experimental works have shown a wide range of functional activ- ities for these molecules. In this paper, we present rNAV (for rna NAVigator), a new tool for the visual exploration and analysis of sRNA-mediated regulatory networks. rNAV has been designed to help bioinformaticians and biologists to identify, from list of thou- sands of predictions, pertinent and reasonable sRNAs and target candidates for carrying out experimental validations. We propose a list of dedicated algorithms and interaction tools that facilitate the exploration of such networks. These algorithms can be gathered into pipelines which can then be saved and reuse over several sessions. To support exploration awareness, rNAV also provides an exploration tree view that allows to navigate through the steps of the analysis but also to select the -sub-networks to visualize and compare. These comparisons are facilitated by the integration of multiple and fully linked views. We demonstrate the usefulness of our approach by a case study on Escherichia coli bacteria performed by domain experts.

Terrain navigation has been used extensively by underwater vehicles the last decade. By comparing bathymetric measurements with a digital terrain model, it estimates a global position of the vehicle underwater, where Global Positioning System (GPS) signals are unavailable. With the increasing threat of GPS signal jammers and spoofers to marine vessels, GPS independent techniques are becoming more interesting for surface vessels as well. This paper explores the idea of using terrain navigation to detect GPS spoofing, and as a substitute position source during GPS jamming. The results from an experiment simulating GPS jamming of a surface vessel indicate the feasibility of such a system.