Articles | Volume 14, issue 5 
            
                
                    
            
            
            https://doi.org/10.5194/amt-14-3583-2021
                    © Author(s) 2021. This work is distributed under 
the Creative Commons Attribution 4.0 License.
                the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/amt-14-3583-2021
                    © Author(s) 2021. This work is distributed under 
the Creative Commons Attribution 4.0 License.
                the Creative Commons Attribution 4.0 License.
Resolving the ambiguous direction of arrival of weak meteor radar trail echoes
                                            Swedish Institute of Space Physics (IRF), Box 812, 98128 Kiruna, Sweden
                                        
                                    
                                            Department of Physics, Umeå University, 90187 Umeå, Sweden
                                        
                                    Johan Kero
                                            Swedish Institute of Space Physics (IRF), Box 812, 98128 Kiruna, Sweden
                                        
                                    Alexander Kozlovsky
                                            Sodankylä Geophysical Observatory, Sodankylä, Finland
                                        
                                    Mark Lester
                                            Department of Physics and Astronomy, University of Leicester, Leicester, United Kingdom
                                        
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                                        Gunter Stober, Sharon L. Vadas, Erich Becker, Alan Liu, Alexander Kozlovsky, Diego Janches, Zishun Qiao, Witali Krochin, Guochun Shi, Wen Yi, Jie Zeng, Peter Brown, Denis Vida, Neil Hindley, Christoph Jacobi, Damian Murphy, Ricardo Buriti, Vania Andrioli, Paulo Batista, John Marino, Scott Palo, Denise Thorsen, Masaki Tsutsumi, Njål Gulbrandsen, Satonori Nozawa, Mark Lester, Kathrin Baumgarten, Johan Kero, Evgenia Belova, Nicholas Mitchell, Tracy Moffat-Griffin, and Na Li
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                                        Daniel Kastinen and Johan Kero
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                                                The behaviour of position determination with interferometric radar systems and possible ambiguities therein depends on the spatial configuration of the radar-receiving antennas and their individual characteristics. We have simulated the position determination performance of five different radar systems. These simulations showed that ambiguities are dynamic and need to be examined on a case-by-case basis. However, the simulations can be used to analyse and understand previously ambiguous data.
                                            
                                            
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                Short summary
            When a meteor enters the atmosphere, it causes a trail of diffusing plasma that moves with the neutral wind. An interferometric radar system can measure such trails and determine its location. However, there is a chance of determining the wrong position due to noise. We simulate this behaviour and use the simulations to successfully determine the true location of ambiguous events. We also successfully test two simple temporal integration methods for avoiding such erroneous determinations.
            When a meteor enters the atmosphere, it causes a trail of diffusing plasma that moves with the...