Novel Integrity Concept for CAT III Precision Approaches and Taxiing: Extended GBAS (E-GBAS)

2011 ◽  
Vol 64 (4) ◽  
pp. 695-710 ◽  
Author(s):  
Wolfgang Schuster ◽  
Washington Ochieng
Keyword(s):  
Measurement Errors ◽  
High Performance ◽  
Performance Monitoring ◽  
Global Navigation Satellite Systems ◽  
Monitoring Scheme ◽  
Satellite Systems ◽  
Accuracy Requirement ◽  
Ground Station ◽  
Full Benefit ◽  
Global Navigation Satellite

Future air navigation envisages increased use of Global Navigation Satellite Systems (GNSS) together with advanced communications and surveillance technologies to facilitate the required increase in capacity, efficiency and safety without adversely impacting the environment. The full benefit of GNSS is expected from its ability to support en-route to en-route or gate-to-gate air navigation. This presents challenges particularly for the phases of flight with stringent required navigation performance. Significant work has so far been devoted to the phases of flight up to CAT I. However, more work is required for CAT III precision landing (with an accuracy requirement at the metre level) and taxiing (with an accuracy requirement at sub-metre level) and both with very high integrity and continuity requirements. The main limitation in using GBAS for CAT III landings is the potential decorrelation of the measurement errors between the GBAS ground station (GGS) and the user. The threats in this respect are the atmospheric anomalies. Periods of strong solar activity can cause large local spatial and temporal gradients in the delays induced on the GNSS signals by the ionosphere. The local nature of the effects results in significant decorrelation between GGS measurements and the user. Therefore, a reliable ground based ionospheric anomaly monitoring scheme is required to guarantee integrity.This paper critically reviews state-of-the-art monitors, identifies their limitations and addresses them by proposing a high-performance monitoring scheme for the ionosphere. Preliminary analyses suggest that the proposed scheme has the potential to enable GNSS to meet the navigation requirements for CAT III and taxiing.

scholarly journals Performance Analyses of a RAIM Algorithm for Kalman Filter with GPS and NavIC Constellations

Sensors ◽  
2021 ◽  
Vol 21 (24) ◽  
pp. 8441
Author(s):  
Susmita Bhattacharyya
Keyword(s):  
Kalman Filter ◽  
Measurement Errors ◽  
Weighted Least Squares ◽  
Temporal Variations ◽  
Global Navigation Satellite Systems ◽  
Model Parameters ◽  
Integrity Monitoring ◽  
Satellite Systems ◽  
Performance Analyses ◽  
Global Navigation Satellite

This paper evaluates the performance of an integrity monitoring algorithm of global navigation satellite systems (GNSS) for the Kalman filter (KF), termed KF receiver autonomous integrity monitoring (RAIM). The algorithm checks measurement inconsistencies in the range domain and requires Schmidt KF (SKF) as the navigation processor. First, realistic carrier-smoothed pseudorange measurement error models of GNSS are integrated into KF RAIM, overcoming an important limitation of prior work. More precisely, the error covariance matrix for fault detection is modified to capture the temporal variations of individual errors with different time constants. Uncertainties of the model parameters are also taken into account. Performance of the modified KF RAIM is then analyzed with the simulated signals of the global positioning system and navigation with Indian constellation for different phases of aircraft flight. Weighted least squares (WLS) RAIM used for comparison purposes is shown to have lower protection levels. This work, however, is important because KF-based integrity monitors are required to ensure the reliability of advanced navigation methods, such as multi-sensor integration and vector receivers. A key finding of the performance analyses is as follows. Innovation-based tests with an extended KF navigation processor confuse slow ramp faults with residual measurement errors that the filter estimates, leading to missed detection. RAIM with SKF, on the other hand, can successfully detect such faults. Thus, it offers a promising solution to developing KF integrity monitoring algorithms in the range domain. The modified KF RAIM completes processing in time on a low-end computer. Some salient features are also studied to gain insights into its working principles.

scholarly journals Ionosphere disturbance during cosmodrome “Vostochniy” launches

2018 ◽  
Vol 62 ◽  
pp. 01008
Author(s):  
Zinaida F. Dumbrava ◽  
Vladimir P. Sivokon ◽  
Yuriy A. Teslyuk ◽  
Sergey Y. Khomutov
Keyword(s):  
Acoustic Waves ◽  
Ionospheric Plasma ◽  
Global Navigation Satellite Systems ◽  
Plasma Properties ◽  
Satellite Systems ◽  
Ground Station ◽  
Ionosphere Disturbance ◽  
Global Navigation Satellite ◽  
Carrier Rocket ◽  
Supersonic Motion

It is known that during spacecraft launches ionospheric plasma properties are modified in the result of impact of shock-acoustic waves generated during carrier rocket supersonic motion. As a rule, investigation of ionospheric plasma variations is carried out by the signals of Global Navigation Satellite Systems GPS/GLONASS that implies ground station network. There is no such a system near the “Vostochniy” cosmodrome that makes it necessary to search for an alternative solution. One of them may be the application of ionosphere vertical and oblique sounding stations. Based on the analysis of such station data, the possibility of evaluation of ionosphere modification during “Vostochniy” cosmodrome launches is shown.

Geolocal – A New System for Geo-Referencing: Analysis of Base Distribution

2020 ◽  
pp. 1-13
Author(s):  
Eduardo P. Macho ◽  
Sergio V.D. Pamboukian ◽  
Emília Correia
Keyword(s):  
Time Delay ◽  
Navigation System ◽  
Measurement Errors ◽  
Global Navigation Satellite Systems ◽  
Navigation Satellite ◽  
Dilution Of Precision ◽  
Satellite Systems ◽  
Global Navigation ◽  
Global Navigation Satellite ◽  
New System

Geolocal is a new navigation system conceived and patented in Brazil, whose purpose is to be independent of other global navigation satellite systems (GNSS). It has an ‘inverted-GNSS’ configuration with at least four bases on the ground at known geodesic position coordinates and a repeater in space. Simulations were performed to determine the precision of Geolocal using different quantities and distributions of bases. They showed that this precision is enhanced when the quantity of bases increases, as long as the elevation angles of the new bases included are higher than the average and when the bases are evenly distributed around the repeater, but mainly when the time delay at the repeater is known in advance and when the measurement errors that generate uncertainties are reduced. The position dilution of precision (PDOP) was also calculated, confirming that precision is enhanced by the quantity of bases and by their distribution.

scholarly journals Antennas as Precise Sensors for GNSS Reference Stations and High-Performance PNT Applications on Earth and in Space

Sensors ◽  
2021 ◽  
Vol 21 (12) ◽  
pp. 4192
Author(s):  
Stefano Caizzone ◽  
Miriam Schönfeldt ◽  
Wahid Elmarissi ◽  
Mihaela-Simona Circiu
Keyword(s):  
Performance Indicators ◽  
High Performance ◽  
Autonomous Driving ◽  
Global Navigation Satellite Systems ◽  
Space Applications ◽  
Research Issues ◽  
Satellite Systems ◽  
Open Research ◽  
Application Fields ◽  
Global Navigation Satellite

Satellite navigation is more and more important in a plethora of very different application fields, ranging from bank transactions to shipping, from autonomous driving to aerial applications, such as commercial avionics as well as unmanned aerial vehicles (UAVs). In very precise positioning, navigation, and timing (PNT) applications, such as in reference stations and precise timing stations, it is important to characterize all errors present in the system in order to account possibly for them or calibrate them out. Antennas play an important role in this respect: they are indeed the “sensor” that capture the signal in space from global navigation satellite systems (GNSS) and thereby strongly contribute to the overall achievable performance. This paper reviews the currently available antenna technologies, targeting specifically reference stations as well as precise GNSS antennas for space applications, and, after introducing performance indicators, summarizes the currently achievable performance. Finally, open research issues are identified, and possible approaches to solve them are discussed.

Study on Differential GPS (DGPS): Method for Reducing the Measurement Error of CNNS

2012 ◽  
Vol 482-484 ◽  
pp. 75-80
Author(s):  
Yong Jiang ◽  
You Xiang Cui ◽  
Bu Feng Li
Keyword(s):  
Measurement Error ◽  
Measurement Errors ◽  
Global Navigation Satellite Systems ◽  
Human Beings ◽  
Differential Gps ◽  
Satellite Systems ◽  
Technological Developments ◽  
The One ◽  
The Individual ◽  
Global Navigation Satellite

Position on the planet has always been vitally important to human beings and today our exact position is something that we can obtain with ease. Among the most stunning technological developments in recent years have been the immense advances in the realm of satellite navigation or Global Navigation Satellite Systems (GNSS) technologies. There are various causes of measurement error. The precision of positioning with GPS navigation depends on the one hand on the precision of the individual pseudorange measurements and on the other hand on the geometric configuration of the satellites used. In order to achieve an accuracy of one meter or better, additional measures are necessary. Reducing the effect of measurement errors can considerably increase the positioning accuracy. Differential GPS (DGPS) is a method for reducing the measurement error of GNNS.

scholarly journals GPS/Galileo Multipath Detection and Mitigation Using Closed-Form Solutions

2009 ◽  
Vol 2009 ◽  
pp. 1-20 ◽  
Author(s):  
Khaled Rouabah ◽  
Djamel Chikouche
Keyword(s):  
High Performance ◽  
High Accuracy ◽  
Global Navigation Satellite Systems ◽  
Line Of Sight ◽  
Satellite Systems ◽  
Closed Form Solutions ◽  
Gnss Positioning ◽  
Simulation Results ◽  
Multipath Detection ◽  
Global Navigation Satellite

We propose an efficient method for the detection of Line of Sight (LOS) and Multipath (MP) signals in global navigation satellite systems (GNSSs) which is based on the use of virtual MP mitigation (VMM) technique. By using the proposed method, the MP signals' delay and coefficient amplitudes can be efficiently estimated. According to the computer simulation results, it is obvious that our proposed method is a solution for obtaining high performance in the estimation and mitigation of MP signals and thus it results in a high accuracy in GNSS positioning.

scholarly journals C3 in UAS as a Means for Secondary Navigation

2012 ◽  
Vol 66 (1) ◽  
pp. 115-134
Author(s):  
Jorge Ramirez ◽  
Dagoberto Salazar ◽  
Xavier Prats ◽  
Cristina Barrado
Keyword(s):  
Kalman Filter ◽  
Global Navigation Satellite Systems ◽  
Civil Aviation ◽  
Navigation Satellite ◽  
International Civil Aviation Organization ◽  
Satellite Systems ◽  
Ground Station ◽  
Performance Based Navigation ◽  
Global Navigation Satellite ◽  
Navigation Accuracy

Unmanned Air Systems (UAS) navigate using Global Navigation Satellite Systems (GNSS), but GNSS vulnerability precludes its use as the only means of navigation and requires a secondary means of navigation. A differentiating characteristic of UAS is their periodic communications with the ground station. This paper analyses the adequacy of employing UAS Command, Control and Communications (C3) as a secondary means of navigation. With no additional infrastructure, an Extended Kalman Filter (EKF) is used to process C3 messages and to obtain the positions of the UAS. Navigation accuracy and integrity are calculated in a scenario with three UAS. The obtained results meet the International Civil Aviation Organization (ICAO) Performance-Based Navigation (PBN) requirements.

scholarly journals Analysis of DME/DME Navigation Performance and Ground Network Using Stretched-Front-Leg Pulse-Based DME

Sensors ◽  
2018 ◽  
Vol 18 (10) ◽  
pp. 3275 ◽  
Author(s):  
Euiho Kim
Keyword(s):  
Measuring Equipment ◽  
Federal Aviation Administration ◽  
The United States ◽  
Significant Loss ◽  
Global Navigation Satellite Systems ◽  
Positioning Accuracy ◽  
Satellite Systems ◽  
Ground Station ◽  
Aircraft Navigation ◽  
Global Navigation Satellite

Global navigation satellite systems (GNSS) have become a primary navigation means for aircraft. However, the signal power of GNSS is very weak, and its service can be disrupted at any time when there is interference or jamming. For this reason, the Federal Aviation Administration (FAA) in the United States has recently chosen a distance measuring equipment (DME)-based aircraft navigation technique, called DME/DME, as an alternative aircraft navigation means for use by around 2030. The reason that the FAA plans to use DME/DME in such a short duration, by around 2030, is presumed to be because the ranging accuracy of DMEs is between 70 to 300 m, which is about 7 to 30 times worse than that of GNSS. Thus, a significant loss of positioning performance is unavoidable with current DMEs. To make DME/DME a more competent alternative positioning source, this paper proposes an advanced DME that could provide a ranging accuracy of around 30 m by employing a recently developed Stretched-Front-Leg (SFOL) pulse. The paper introduces optimal ground station augmentation algorithms that help to efficiently transform the current DME ground network to enable a DME/DME positioning accuracy of up to 0.3 nm or 92.6 m with a minimal number of new ground DME sites. The positioning performance and augmented ground network using the proposed SFOL pulse-based DME are evaluated in two regions which have distinct terrain conditions.

Sign in / Sign up

Export Citation Format

Share Document