Please wait, while we are loading the content...
Please wait, while we are loading the content...
Content Provider | IET Digital Library |
---|---|
Author | Brahim, Fadoua Chonavel, Thierry Trubuil, Joel Boudraa, Abdel Ouahab |
Abstract | New Galileo and enhanced GPS signals use binary offset carrier (BOC) waveforms namely composite BOC (CBOC) and alternate BOC (AltBOC). For good tracking, these signals require precise acquisition. The more sidelobes the autocorrelation function has, the tighter the pull-in range region is, and the more precise the acquisition must be. Further, when multipath propagation is encountered, the received waveform is so distorted that a precise acquisition becomes difficult. To solve this problem, two approaches are considered by enhancing either the acquisition stage or the tracking one. At the acquisition stage, the authors focus on Bayesian estimation where Bernoulli–Gaussian and Laplacian (Lp) priors for channel distribution are compared. On one hand, the BG prior leads to rather complex optimisation criterion that can be solved by a Markov Chain Monte Carlo algorithm. This is a very efficient but time consuming method. On the other hand, the Lp prior results in exact maximum a posteriori calculation. In this case, the Bayesian estimation involves an ℓ1-norm penalisation and provides quite good performance for reasonable acquisition complexity. At the tracking stage, many works have dealt with false lock positions, such as the sidelobe cancellation method (SCM) or multiple gate delay (MGD) technique. In this article, the authors highlight the need for accurate acquisition for better detection and estimation at the tracking output. The SCM and MGD methods are taken as examples to illustrate this influence. The analysed signals are GPS BPSK(1), BPSK(10), and Galileo CBOC(6, 1, 1/11) and AltBOC(15, 10) modulated open service signals. The impact of multipath is studied for line of sight (LOS) signal, LOS plus multipath replicas, and multipath alone. The authors compare the results of classical acquisition followed by precise tracking to those of Bayesian acquisition followed by classical tracking. The results of Bayesian acquisition followed by precise tracking are also provided. |
Starting Page | 790 |
Ending Page | 801 |
Page Count | 12 |
ISSN | 17518784 |
Volume Number | 9 |
e-ISSN | 17518792 |
Issue Number | Issue 7, Aug (2015) |
Alternate Webpage(s) | https://digital-library.theiet.org/content/journals/iet-rsn/9/7 |
Alternate Webpage(s) | https://digital-library.theiet.org/content/journals/10.1049/iet-rsn.2014.0210 |
Journal | IET Radar, Sonar & Navigation |
Publisher Date | 2015-04-16 |
Access Restriction | Open |
Rights Holder | © The Institution of Engineering and Technology |
Subject Keyword | AltBOC Signal Analysis Alternate BOC Autocorrelation Function Bayes Method Bayesian Acquisition Bayesian Estimation Bernoulli-Gaussian Estimation Binary Offset Carrier Waveform Channel Distribution Complex Optimisation Criterion Composite BOC Waveform Correlation Method Exact Maximum A Posteriori Calculation False Lock Position Galileo CBOC Signal Analysis Galileo GPS Signal Tracking Global Navigation Satellite System Signal Precise Acquisition Global Positioning System GPS BPSK Signal Analysis Laplacian Estimation Line of Sight Signal LOS Plus Multipath Replicas Markov Chain Monte Carlo Algorithm Markov Processes Maximum Likelihood Detection Maximum Likelihood Estimation Modulation And Coding Method Monte Carlo Method Multipath Propagation Optimisation Optimisation Technique Phase Shift Keying Radio Navigation And Direction Finding Signal Detection Wireless Channel ℓ1-norm Penalisation |
Content Type | Text |
Resource Type | Article |
Subject | Electrical and Electronic Engineering |
National Digital Library of India (NDLI) is a virtual repository of learning resources which is not just a repository with search/browse facilities but provides a host of services for the learner community. It is sponsored and mentored by Ministry of Education, Government of India, through its National Mission on Education through Information and Communication Technology (NMEICT). Filtered and federated searching is employed to facilitate focused searching so that learners can find the right resource with least effort and in minimum time. NDLI provides user group-specific services such as Examination Preparatory for School and College students and job aspirants. Services for Researchers and general learners are also provided. NDLI is designed to hold content of any language and provides interface support for 10 most widely used Indian languages. It is built to provide support for all academic levels including researchers and life-long learners, all disciplines, all popular forms of access devices and differently-abled learners. It is designed to enable people to learn and prepare from best practices from all over the world and to facilitate researchers to perform inter-linked exploration from multiple sources. It is developed, operated and maintained from Indian Institute of Technology Kharagpur.
Learn more about this project from here.
NDLI is a conglomeration of freely available or institutionally contributed or donated or publisher managed contents. Almost all these contents are hosted and accessed from respective sources. The responsibility for authenticity, relevance, completeness, accuracy, reliability and suitability of these contents rests with the respective organization and NDLI has no responsibility or liability for these. Every effort is made to keep the NDLI portal up and running smoothly unless there are some unavoidable technical issues.
Ministry of Education, through its National Mission on Education through Information and Communication Technology (NMEICT), has sponsored and funded the National Digital Library of India (NDLI) project.
Sl. | Authority | Responsibilities | Communication Details |
---|---|---|---|
1 | Ministry of Education (GoI), Department of Higher Education |
Sanctioning Authority | https://www.education.gov.in/ict-initiatives |
2 | Indian Institute of Technology Kharagpur | Host Institute of the Project: The host institute of the project is responsible for providing infrastructure support and hosting the project | https://www.iitkgp.ac.in |
3 | National Digital Library of India Office, Indian Institute of Technology Kharagpur | The administrative and infrastructural headquarters of the project | Dr. B. Sutradhar bsutra@ndl.gov.in |
4 | Project PI / Joint PI | Principal Investigator and Joint Principal Investigators of the project |
Dr. B. Sutradhar bsutra@ndl.gov.in Prof. Saswat Chakrabarti will be added soon |
5 | Website/Portal (Helpdesk) | Queries regarding NDLI and its services | support@ndl.gov.in |
6 | Contents and Copyright Issues | Queries related to content curation and copyright issues | content@ndl.gov.in |
7 | National Digital Library of India Club (NDLI Club) | Queries related to NDLI Club formation, support, user awareness program, seminar/symposium, collaboration, social media, promotion, and outreach | clubsupport@ndl.gov.in |
8 | Digital Preservation Centre (DPC) | Assistance with digitizing and archiving copyright-free printed books | dpc@ndl.gov.in |
9 | IDR Setup or Support | Queries related to establishment and support of Institutional Digital Repository (IDR) and IDR workshops | idr@ndl.gov.in |
Loading...
|