Publications
338 results found
Ochieng WY, Quddus MA, North RJ, et al., 2010, Technologies to measure indicators for road user charging, PROCEEDINGS OF THE INSTITUTION OF CIVIL ENGINEERS-TRANSPORT, Vol: 163, Pages: 63-72, ISSN: 0965-092X
- Author Web Link
- Cite
- Citations: 3
Milner CD, Ochieng WY, 2010, A fast and efficient integrity computation for non-precision approach performance assessment, GPS SOLUTIONS, Vol: 14, Pages: 193-205, ISSN: 1080-5370
- Author Web Link
- Cite
- Citations: 11
Porretta M, Schuster W, Majumdar A, et al., 2010, Strategic Conflict Detection and Resolution Using Aircraft Intent Information, JOURNAL OF NAVIGATION, Vol: 63, Pages: 61-88, ISSN: 0373-4633
- Author Web Link
- Cite
- Citations: 6
Feng S, Ochieng W, Samson J, et al., 2010, Integrity Monitoring for Carrier Phase Ambiguities, 23rd International Technical Meeting of the Satellite Division of the Institute-of-Navigation (ION GNSS-2010), Publisher: INST NAVIGATION, Pages: 2148-2159, ISSN: 2331-5911
- Author Web Link
- Cite
- Citations: 1
Schuster W, Ochieng W, Porretta M, 2010, HIGH-PERFORMANCE TRAJECTORY PREDICTION FOR CIVIL AIRCRAFT, 29th Digital Avionics Systems Conference on Improving Our Environment through Green Avionics and ATM Solutions, Publisher: IEEE, ISSN: 2155-7195
- Author Web Link
- Cite
- Citations: 5
Schuster W, Ochieng W, 2010, Harmonisation of Category-III Precision Approach Performance Requirements, Journal of Navigation, Pages: 569-589
Quddus MA, Ochieng WY, Liu H, 2010, EDITORIAL: Special Issue: Intelligent Vehicle Navigation (Part 2), JOURNAL OF INTELLIGENT TRANSPORTATION SYSTEMS, Vol: 14, Pages: 1-2, ISSN: 1547-2450
Porretta M, Schuster W, Majumdar A, et al., 2010, Strategic Conflict Detection and Resolution Using Aircraft Intent Information, Pages: 61-88
Quddus MA, Noland RB, Ochieng WY, 2009, The Effects of Navigation Sensors and Spatial Road Network Data Quality on the Performance of Map Matching Algorithms, GEOINFORMATICA, Vol: 13, Pages: 85-108, ISSN: 1384-6175
- Author Web Link
- Cite
- Citations: 19
Feng S, Ochieng W, Moore T, et al., 2009, Carrier phase-based integrity monitoring for high-accuracy positioning, GPS SOLUTIONS, Vol: 13, Pages: 13-22, ISSN: 1080-5370
- Author Web Link
- Cite
- Citations: 65
Panagiotakopoulos D, Majumdar A, Ochieng W, 2009, Characterizing the Distribution of Safety Occurrences in Aviation An Approach Using Extreme Value Theory, TRANSPORTATION RESEARCH RECORD, Pages: 129-140, ISSN: 0361-1981
- Author Web Link
- Cite
- Citations: 4
Peng B, Mautz R, Kemp AH, et al., 2008, On the effect of localization errors on geographic routing in sensor networks, Pages: 3136-3140, ISSN: 0536-1486
Recently, network localization systems that are based on inter-node ranges have received significant attention. Geographic routing has been considered an application which can utilize the location information from these localization systems. In this paper, we firstly recognize that sensor network localization algorithms generate positioning data with different error patterns compared to those networks where node positions are determined directly from GNSS measurements. Secondly, by simulating practical sensor network scenarios using data from our localization algorithm, we observe that existing geographic routing algorithms in wireless sensor networks (WSNs) adopt very simplistic methods in the treatment of position error, without due consideration of error distribution. Additionally, an insight is given into localization algorithms for WSNs with inhomogeneous error environments. Our observations represent an initial step toward a detailed understanding and design of efficient geographic routing algorithms in location aware WSNs. ©2008 IEEE.
Porretta M, Dupuy M-D, Schuster W, et al., 2008, Performance evaluation of a novel 4D trajectory prediction model for civil aircraft, JOURNAL OF NAVIGATION, Vol: 61, Pages: 393-420, ISSN: 0373-4633
- Author Web Link
- Cite
- Citations: 20
Bai J, Schuster W, Ochieng W, 2008, Advanced Navigation Algorithms for Airport Surface Movement – Developments and Performance, European Navigation Conference - ENC GNSS
Panagiotakopoulos D, Ochieng WY, Niemman P, 2008, Robust statistical framework for monitoring the integrity of space-based navigation systems
Integrity monitoring of satellite navigation systems such as the Global Positioning System offers a level of protection against potentially hazardous failures or malfunctions. As satellite navigation is used for a wide array of applications including liability and/or safety critical ones, ensuring the safety of the broadcast signals is a higher priority than ever. However current methods for integrity monitoring are limited by the assumptions they make on the characteristics of the residual navigation errors, used in the computation of the protection levels which form the basis for the design of the integrity algorithms. In particular, it has been a standard assumption in the design and analysis of navigation systems that all noise sources are independent and have a zero mean Gaussian probability density function in the absence of failures. This error distribution model assumption has been instrumental in the development of real-life systems as it allows for relatively simple metrics for tradeoff purposes in system design and is the underlying principle in the design of almost all algorithms in GNSS based systems, including the derivation of the integrity equations for Ground Based Augmentation Systems (GBAS) and Space Based Augmentation Systems (SBAS). It has long been known that in practice, pseudorange residual errors although not very different from normal laws, may not have normal tails, or not have a zero mean. Until recently there were insufficient data to demonstrate fully the nature of the distribution of residual errors. Various alternative distributions have been suggested over the years but none has been shown to be satisfactory. The current approach that is used to overcome this issue is through overbounding, in a mathematical sense, a technique that considers an error distribution more conservative than the actual one for the computation of the protection levels. This has resulted in a widespread tendency to derive over-bounding distributions, such as
Noland RR, Quddus MA, Ochieng WY, 2008, The effect of the London congestion charge on road casualties: an intervention analysis, TRANSPORTATION, Vol: 35, Pages: 73-91, ISSN: 0049-4488
- Author Web Link
- Cite
- Citations: 33
Porretta M, Dupuy M-D, Schuster W, et al., 2008, Performance Evaluation of a Novel 4D Trajectory Prediction Model for Civil Aircraft, Journal of Navigation, Pages: 393-420
Feng S, Ochieng W, North R, 2008, Quantitative Measures for GPS Based Road User Charging, 11th IEEE International Conference on Intelligent Transportation Systems (ITSC 2008), Publisher: IEEE, Pages: 495-500
Schuster W et al, 2008, Satellite-based Navigation Architecture Study for Aircraft Category III Landings, ICAS
Schuster W, Bai J, Feng S, et al., 2008, Airport Surface Movement – Performance Requirements, Architecture Considerations & Integrity Algorithms, International Civil Aviation Organisation (ICAO)
Schuster W, Bai J, Ochieng W, et al., 2008, High Performance Navigation Algorithms for Aviation – Results of Approach and Airport Surface Movement Tests, IONI GNSS
Quddus MA, Ochieng WY, Liu H, 2008, EDITORIAL: Special Issue: Intelligent Vehicle Navigation (Part1), JOURNAL OF INTELLIGENT TRANSPORTATION SYSTEMS, Vol: 12, Pages: 157-158, ISSN: 1547-2450
- Author Web Link
- Cite
- Citations: 5
Ziebart M, Cross P, Sibthorpe A, et al., 2007, Single epoch estimation of the Galileo integrity chain sensor station clock offsets, GPS SOLUTIONS, Vol: 11, Pages: 227-237, ISSN: 1080-5370
Williams V, Noland RB, Majumdar A, et al., 2007, Reducing environmental impacts of aviation with innovative air traffic management technologies, AERONAUTICAL JOURNAL, Vol: 111, Pages: 741-749, ISSN: 0001-9240
- Author Web Link
- Cite
- Citations: 6
Quddus MA, Ochieng WY, Noland RB, 2007, Current map-matching algorithms for transport applications: State-of-the art and future research directions, TRANSPORTATION RESEARCH PART C-EMERGING TECHNOLOGIES, Vol: 15, Pages: 312-328, ISSN: 0968-090X
- Author Web Link
- Cite
- Citations: 564
Feng S, Ochieng W, 2007, A difference test method for early detection of slowly growing errors in GNSS positioning, JOURNAL OF NAVIGATION, Vol: 60, Pages: 427-442, ISSN: 0373-4633
- Author Web Link
- Cite
- Citations: 7
Bhatti UI, Ochieng WY, Feng S, 2007, Integrity of an integrated GPS/INS system in the presence of slowly growing errors. Part II: analysis, GPS SOLUTIONS, Vol: 11, Pages: 183-192, ISSN: 1080-5370
- Author Web Link
- Cite
- Citations: 29
Bhatti UI, Ochieng WY, Feng S, 2007, Integrity of an integrated GPS/INS system in the presence of slowly growing errors. Part I: A critical review, GPS SOLUTIONS, Vol: 11, Pages: 173-181, ISSN: 1080-5370
- Author Web Link
- Cite
- Citations: 42
Subotic B, Ochieng WY, Straeter O, 2007, Recovery from equipment failures in ATC: Determination of contextual factors, RELIABILITY ENGINEERING & SYSTEM SAFETY, Vol: 92, Pages: 858-870, ISSN: 0951-8320
- Author Web Link
- Cite
- Citations: 12
Bhatti UI, Ochieng WY, 2007, Failure modes and models for integrated GPS/INS systems, Journal of Navigation, Vol: 60, Pages: 327-348, ISSN: 0373-4633
GPS is the most widely used global navigation satellite system. By design, there is no provision for real time integrity information within the Standard Positioning Service (SPS). However, in safety critical sectors like aviation, stringent integrity performance requirements must be met. This can be achieved externally or at the receiver level through receiver autonomous integrity monitoring (RAIM). The latter is a cost effective method that relies on data consistency, and therefore requires redundant measurements. An external aid to provide this redundancy can be in the form of an Inertial Navigation System (INS). This should enable continued performance even during RAIM holes (when no redundant satellite measurements are available). However, due to the inclusion of an additional system and the coupling mechanism, integrity issues become more challenging. To develop an effective integrity monitoring capability, a good understanding of the potential failure modes of the integrated system is vital. In this paper potential failure modes of integrated GPS/INS systems are identified. This is followed by the specification of corresponding models that would be required to investigate the capability of existing integrity algorithms and to develop enhancements or new algorithms. © The Royal Institute of Navigation.
This data is extracted from the Web of Science and reproduced under a licence from Thomson Reuters. You may not copy or re-distribute this data in whole or in part without the written consent of the Science business of Thomson Reuters.