author = "Moraes, Alison de O. and Vani, Bruno C. and Costa, Emanoel and 
                         Abdu, Mangalathayil Ali and Paula, Eurico Rodrigues de and 
                         Sousasantos, Jonas and Monico, Jo{\~a}o F. G. and Forte, Biagio 
                         and Negreti, Patr{\'{\i}}cia Mara de Siqueira and Shimabukuro, 
                         Milton Hirokazu",
          affiliation = "{Instituto de Aeron{\'a}utica e Espa{\c{c}}o (IAE)} and 
                         Instituto Federal de Educa{\c{c}}{\~a}o, Ci{\^e}ncia e 
                         Tecnologia de S{\~a}o Paulo, Campus Presidente Epit{\'a}cio 
                         (IFSP-PEP) and {Pontif{\'{\i}}cia Universidade Cat{\'o}lica do 
                         Rio de Janeiro (PUC-Rio)} and {Instituto Tecnol{\'o}gico de 
                         Aeron{\'a}utica (ITA)} and {Instituto Nacional de Pesquisas 
                         Espaciais (INPE)} and {Instituto Tecnol{\'o}gico de 
                         Aeron{\'a}utica (ITA)} and {Universidade Estadual Paulista 
                         (UNESP)} and {University of Bath} and {Instituto Nacional de 
                         Pesquisas Espaciais (INPE)} and {Universidade Estadual Paulista 
                title = "GPS availability and positioning issues when the signal paths are 
                         aligned with ionospheric plasma bubbles",
              journal = "GPS Solutions",
                 year = "2018",
               volume = "22",
               number = "4",
                pages = "UNSP 95",
                month = "Oct.",
             keywords = "Ionospheric scintillation, Fading distribution, GPS 
             abstract = "The propagation paths of signals through equatorial ionospheric 
                         irregularities are analyzed by evaluating their effects on Global 
                         Navigation Satellite System (GNSS) positioning and availability. 
                         Based on observations during 32 days by a scintillation monitor at 
                         So Jos, dos Campos, Brazil, it was noted that there is a dominance 
                         of enhanced scintillation events for Global Positioning System 
                         (GPS) ray paths aligned with the azimuth angle of 345A degrees 
                         (geographic northwest). This azimuth corresponds to the magnetic 
                         meridian that has a large westward declination angle in the region 
                         (21.4AW). Such results suggest that the enhanced scintillation 
                         events were associated with GPS signals that propagated through 
                         plasma bubbles aligned along the direction of the magnetic field. 
                         It will be shown that, under this alignment condition, the longer 
                         propagation path length through plasma bubbles can result in more 
                         severe scintillation cases and more losses of signal lock, as 
                         supported by proposed statistics of bit error probability and mean 
                         time between cycle slips. Additionally, large precise positioning 
                         errors are also related to these events, as demonstrated by 
                         precise point positioning experiments.",
                  doi = "10.1007/s10291-018-0760-8",
                  url = "http://dx.doi.org/10.1007/s10291-018-0760-8",
                 issn = "1080-5370 and 1521-1886",
             language = "en",
           targetfile = "Moraes_GPS.pdf",
        urlaccessdate = "30 nov. 2020"