Analysis and design on frozen condition of near-earth near-circluar orbit in critical inclination

The frozen condition of near-earth near-circluar orbit in critical inclination was studied in this paper. The frozen theory which based on J2 and J3 earth zonal harmonics can not explain the evolvement of eccentricity and argument of periapsis in near-circluar orbit in critical inclination by factual measure data, it needs consider more higher earth zonal harmonics perturbations. At the same tine, there is the coupling phenomena exists between eccentricity and argument of periapsis. if the initial argument of periapsis is set to 180°, the change of eccentricity and argument of periapsis will appear singularity by theory analysis and numerical simulation. The eccentricity will decrease firstly and then begin to increase, and the argument of periapsis can maintain at 180° and 0°. Finally, the passive orbit control strategy and initiative orbit control strategy were put forward based on the analysis result.