ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Articles  (170)
  • Hindawi  (170)
  • American Geophysical Union
  • American Meteorological Society
  • American Society of Civil Engineers
  • Blackwell Publishing Ltd
  • Copernicus
  • Molecular Diversity Preservation International
  • Springer Nature
  • Springer Science + Business Media
  • Wiley
  • 2020-2022
  • 2010-2014  (170)
  • 1960-1964
  • International Journal of Navigation and Observation  (105)
  • 97417
  • Architecture, Civil Engineering, Surveying  (170)
  • Mathematics
Collection
  • Articles  (170)
Source
Publisher
  • Hindawi  (170)
  • American Geophysical Union
  • American Meteorological Society
  • American Society of Civil Engineers
  • Blackwell Publishing Ltd
    • +
Years
Year
Journal
Topic
  • Architecture, Civil Engineering, Surveying  (170)
  • Mathematics
  • Geosciences  (170)
  • 1
    facet.materialart.
    Unknown
    Navigation Facility for High Accuracy Offline Trajectory and Attitude Estimation in Airborne Applications (2013)
    Hindawi
    Details
    Publication Date: 2013-09-06
    Description: The paper focuses on a navigation facility, relying on commercial-off-the-shelf (COTS) technology, developed to generate high-accuracy attitude and trajectory measurements in postprocessing. Target performance is cm-level positioning with tenth of degree attitude accuracy. The facility is based on the concept of GPS-aided inertial navigation but comprises carrier-phase differential GPS (CDGPS) processing and attitude estimation based on multiantenna GPS configurations. Expected applications of the system include: (a) performance assessment of integrated navigation systems, developed for general aviation aircraft and medium size unmanned aircraft systems (UAS); (b) generation of reference measurements to evaluate the flight performance of airborne sensors (e.g., radar or laser); and (c) generation of reference trajectory and attitude for improving imaging quality of airborne remote sensing data. The paper describes system architecture, selected algorithms for data processing and integration, and theoretical performance evaluation. Experimental results are also presented confirming the effectiveness of the implemented approach.
    Print ISSN: 1687-5990
    Electronic ISSN: 1687-6008
    Topics: Architecture, Civil Engineering, Surveying , Geosciences
    Published by Hindawi
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 2
    facet.materialart.
    Unknown
    Time Synchronization and Performance of BeiDou Satellite Clocks in Orbit (2013)
    Hindawi
    Details
    Publication Date: 2013-09-06
    Description: The time model of Beidou satellite clocks is analyzed. The general relations of satellite clocks with the system time are studied. The error sources of two-way radio time transfer between satellites and uplink stations are analyzed. The uncertainty of type A is about 0.3 ns in Beidou system. All the satellite clocks in orbit of Beidou satellite navigation system are evaluated by the clock offsets observed by the two-way radio time transfer. The frequency stabilities at a sample time of 10000 s and 1 day for all the satellite clocks are better than . It means that the performance of Beidou satellite clocks in orbit is consistent with the ground test, and the results in orbit are a little better than those in ground vacuum.
    Print ISSN: 1687-5990
    Electronic ISSN: 1687-6008
    Topics: Architecture, Civil Engineering, Surveying , Geosciences
    Published by Hindawi
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 3
    facet.materialart.
    Unknown
    Kalman Filter-Based Hybrid Indoor Position Estimation Technique in Bluetooth Networks (2013)
    Hindawi
    Details
    Publication Date: 2013-09-23
    Description: This paper presents an extended Kalman filter-based hybrid indoor position estimation technique which is based on integration of fingerprinting and trilateration approach. In this paper, Euclidian distance formula is used for the first time instead of radio propagation model to convert the received signal to distance estimates. This technique combines the features of fingerprinting and trilateration approach in a more simple and robust way. The proposed hybrid technique works in two stages. In the first stage, it uses an online phase of fingerprinting and calculates nearest neighbors (NN) of the target node, while in the second stage it uses trilateration approach to estimate the coordinate without the use of radio propagation model. The distance between calculated NN and detective access points (AP) is estimated using Euclidian distance formula. Thus, distance between NN and APs provides radii for trilateration approach. Therefore, the position estimation accuracy compared to the lateration approach is better. Kalman filter is used to further enhance the accuracy of the estimated position. Simulation and experimental results validate the performance of proposed hybrid technique and improve the accuracy up to 53.64% and 25.58% compared to lateration and fingerprinting approaches, respectively.
    Print ISSN: 1687-5990
    Electronic ISSN: 1687-6008
    Topics: Architecture, Civil Engineering, Surveying , Geosciences
    Published by Hindawi
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 4
    facet.materialart.
    Unknown
    Experimental Evaluation of Cooperative Relative Positioning for Intelligent Transportation System (2014)
    Hindawi
    Details
    Publication Date: 2014-12-01
    Description: Support system for safe driving heavily depends on global navigation satellite system. Pseudoranges between satellites and vehicles are measured to compute vehicles’ positions and their relative positions. In urban areas, however, multipath errors (MPEs) in pseudoranges, caused by obstruction and reflection of roadside buildings, greatly degrade the precision of relative positions. On the other hand, simply removing all reflected signals might lead to a shortage of satellites in fixing positions. In our previous work, we suggested solving this dilemma by cooperative relative positioning (CoRelPos) which exploits spatial correlation of MPEs. In this paper, we collected the trace data of pseudoranges by driving cars in urban areas, analyzed the properties of MPEs (specifically, their dependency on signal strength, elevation angles of satellites, and receivers’ speeds), and highlighted their spatial correlation. On this basis, the CoRelPos scheme is refined by considering the dynamics of MPEs. Evaluation results under practical vehicular scenarios confirm that properties of MPEs can be exploited to improve the precision of relative positions.
    Print ISSN: 1687-5990
    Electronic ISSN: 1687-6008
    Topics: Architecture, Civil Engineering, Surveying , Geosciences
    Published by Hindawi
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 5
    facet.materialart.
    Unknown
    Two-Step Galileo E1 CBOC Tracking Algorithm: When Reliability and Robustness Are Keys! (2013)
    Hindawi
    Details
    Publication Date: 2013-03-07
    Description: The majority of 3G mobile phones have an integrated GPS chip enabling them to calculate a navigation solution. But to deliver continuous and accurate location information, the satellite tracking process has to be stable and reliable. This is still challenging, for example, in heavy multipath and non-line of sight (NLOS) environments. New families of Galileo and GPS navigation signals, such as Alternate Binary Offset Carrier (AltBOC), Composite Binary Offset Carrier (CBOC), and Time-Multiplex Binary Offset Carrier (TMBOC), will bring potential improvements in the pseudorange calculation, including more signal power, better multipath mitigation capabilities, and overall more robust navigation. However, GNSS signal tracking strategies have to be more advanced in order to profit from the enhanced properties of the new signals.In this paper, a tracking algorithm designed for Galileo E1 CBOC signal that consists of two steps, coarse and fine, with different tracking parameters in each step, is presented and analyzed with respect to tracking accuracy, sensitivity and robustness. The aim of this paper is therefore to provide a full theoretical analysis of the proposed two-step tracking algorithm for Galileo E1 CBOC signals, as well as to confirm the results through simulations as well as using real Galileo satellite data.
    Print ISSN: 1687-5990
    Electronic ISSN: 1687-6008
    Topics: Architecture, Civil Engineering, Surveying , Geosciences
    Published by Hindawi
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 6
    facet.materialart.
    Unknown
    A Novel Quasi-Open Loop Architecture for GNSS Carrier Recovery Systems (2013)
    Hindawi
    Details
    Publication Date: 2013-03-07
    Description: The problem of designing robust systems to track global navigation satellite system (GNSS) signals in harsh environments has gained high attention. The classical closed loop architectures, such as phase locked loops, have been used for many years for tracking, but in challenging applications their design procedure becomes intricate. This paper proposes and demonstrates the use of a quasi-open loop architecture to estimate the time varying carrier frequency of GNSS signals. Simulation results show that this scheme provides an additional degree of freedom to the design of the whole architecture. In particular, this additional degree of freedom eases the design of the loop filter in harsh environments.
    Print ISSN: 1687-5990
    Electronic ISSN: 1687-6008
    Topics: Architecture, Civil Engineering, Surveying , Geosciences
    Published by Hindawi
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 7
    facet.materialart.
    Unknown
    A New Multipath Mitigation Method for GNSS Receivers Based on an Antenna Array (2013)
    Hindawi
    Details
    Publication Date: 2013-03-07
    Description: The well-known Space-Alternating Generalized Expectation Maximisation (SAGE) algorithm has been recently considered for multipath mitigation in Global Navigation Satellite System (GNSS) receivers. However, the implementation of SAGE in a GNSS receiver is a challenging issue due to the numerous number or parameters to be estimated and the important size of the data to be processed. A new implementation of the SAGE algorithm is proposed in this paper in order to reach the same efficiency with a reduced complexity. This paper focuses on the trade-off between complexity and performance thanks to the Cramer Rao bound derivation. Moreover, this paper shows how the proposed algorithm can be integrated with a classical GNSS tracking loop. This solution is thus a very promising approach for multipath mitigation.
    Print ISSN: 1687-5990
    Electronic ISSN: 1687-6008
    Topics: Architecture, Civil Engineering, Surveying , Geosciences
    Published by Hindawi
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 8
    facet.materialart.
    Unknown
    Nonlinear Bayesian Tracking Loops for Multipath Mitigation (2013)
    Hindawi
    Details
    Publication Date: 2013-03-07
    Description: This paper studies Bayesian filtering techniques applied to the design of advanced delay tracking loops in GNSS receivers with multipath mitigation capabilities. The analysis includes tradeoff among realistic propagation channel models and the use of a realistic simulation framework. After establishing the mathematical framework for the design and analysis of tracking loops in the context of GNSS receivers, we propose a filtering technique that implements Rao-Blackwellization of linear states and a particle filter for the nonlinear partition and compare it to traditional delay lock loop/phase lock loop-based schemes.
    Print ISSN: 1687-5990
    Electronic ISSN: 1687-6008
    Topics: Architecture, Civil Engineering, Surveying , Geosciences
    Published by Hindawi
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 9
    facet.materialart.
    Unknown
    Accurate GLONASS Time Transfer for the Generation of the Coordinated Universal Time (2012)
    Hindawi
    Details
    Publication Date: 2012-09-26
    Description: The spatial techniques currently used in accurate time transfer are based on GPS, TWSTFT, and GLONASS. The International Bureau of Weights and Measures (BIPM) is mandated for the generation of Coordinated Universal Time (UTC) which is published monthly in the BIPM Circular T. In 2009, the international Consultative Committee for Time and Frequency (CCTF) recommended the use of multitechniques in time transfer to ensure precision, accuracy, and robustness in UTC. To complement the existing GPS and TWSTFT time links, in November 2009 the first two GLONASS time links were introduced into the UTC worldwide time link network. By November 2011, 6 GLONASS time links are used in the UTC computation. In the frame of the application in the UTC computation, we establish the technical features of GLONASS time transfer: the short- and long-term stabilities, the calibration process, and in particular the impact of the multiple GLONASS frequency biases. We then outline various considerations for future developments, including the uses of P-codes and carrier-phase information.
    Print ISSN: 1687-5990
    Electronic ISSN: 1687-6008
    Topics: Architecture, Civil Engineering, Surveying , Geosciences
    Published by Hindawi
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 10
    facet.materialart.
    Unknown
    Effectiveness of GNSS Spoofing Countermeasure Based on Receiver CNR Measurements (2012)
    Hindawi
    Details
    Publication Date: 2012-07-18
    Description: A perceived emerging threat to GNSS receivers is posed by a spoofing transmitter that emulates authentic signals but with randomized code phase and Doppler over a small range. Such spoofing signals can result in large navigational solution errors that are passed onto the unsuspecting user with potentially dire consequences. In this paper, a simple and readily implementable processing rule based on CNR estimates of the correlation peaks of the despread GNSS signals is developed expressly for reducing the effectiveness of such a spoofer threat. Consequently, a comprehensive statistical analysis is given to evaluate the effectiveness of the proposed technique in various LOS and NLOS environments. It is demonstrated that the proposed receiver processing is highly effective in both line-of-sight and multipath propagation conditions.
    Print ISSN: 1687-5990
    Electronic ISSN: 1687-6008
    Topics: Architecture, Civil Engineering, Surveying , Geosciences
    Published by Hindawi
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...