author = "Merguizo Sanchez, Diogo and Yokoyama, Tadashi and Prado, Antonio 
                         Fernando Bertachini de Almeida",
          affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and 
                         {Universidade Estadual Paulista (UNESP)} and {Instituto Nacional 
                         de Pesquisas Espaciais (INPE)}",
                title = "Study of some strategies for disposal of the GNSS satellites",
              journal = "Mathematical Problems in Engineering",
                 year = "2015",
               volume = "2015",
                pages = "382340",
             abstract = "The complexity of the GNSS and the several types of satellites in 
                         the MEO region turns the creation of a definitive strategy to 
                         dispose the satellites of this system into a hard task. Each 
                         constellation of the system adopts its own disposal strategy; for 
                         example, in the American GPS, the disposal strategy consists in 
                         changing the altitude of the nonoperational satellites to 
                         500\ km above or below their nominal orbits. In this work, 
                         we propose simple but efficient techniques to discard satellites 
                         of the GNSS by exploiting Hohmann type maneuvers combined with the 
                         use of the resonance to increase its orbital eccentricity, thus 
                         promoting atmospheric reentry. The results are shown in terms of 
                         the increment of velocity required to transfer the satellites to 
                         the new orbits. Some comparisons with direct disposal maneuvers 
                         (Hohmann type) are also presented. We use the exact equations of 
                         motion, considering the perturbations of the Sun, the Moon, and 
                         the solar radiation pressure. The geopotential model was 
                         considered up to order and degree eight. We showed the 
                         quantitative influence of the sun and the moon on the orbit of 
                         these satellites by using the method of the integral of the forces 
                         over the time.",
                  doi = "10.1155/2015/382340",
                  url = "http://dx.doi.org/10.1155/2015/382340",
                 issn = "1024-123X",
             language = "en",
           targetfile = "sanchez_study.pdf",
        urlaccessdate = "26 jan. 2021"