The dual-mode method for monitoring the earth’s surface and the analysis of possible usage in the operation of spacecraft earth remote sensing

At the moment the Earth’s remote sensing spacecrafts (ERS SC) have found a wide practical application for solving different social and economical objectives, such as getting the information from emergency areas or areas with a low developed ground infrastructure. The major disadvantage of modern ERS SCs is a low efficiency of getting the information from the specified areas of the ground. The existing ways to decrease supervision frequency for a specified ground surface area suppose a vast increase of ERS SC group’s number. However, this way requires large economic costs. The authors have proposed a dual-mode method for monitoring the Earth’s surface. This way foresees to use a mode of global supervision and a mode of regional supervision while in ERC SC operation. The transfer from one mode to another is proposed to be performed by the period change of SC’s circuit of Earth with changing the bigger semi-axis of working orbit using a service propulsion system. In the frames of performed researches a method was created to define the main orbit parameters for global and regional supervisions. To ensure an ERS SC to pass a way through the defined area of the Earth’s surface, we considered phasing when transferring to the mode of regional supervision. As the result, it was developed a definition method of time and financial costs for the supervision mode changing. As it was required to describe mathematically the interconnection of working point, referring to the phasing orbit, with the geographical coordinates of the defined ground area, the authors have developed the method to calculate the ERS SC ways, operating with the application of the dual-mode method for monitoring. The mentioned above methods are the integral parts of the mathematic model, describing the dual-mode method for monitoring, which will become a basis for forming the requirements to the future engines and power plants of spacecrafts. The comparing of the two-mode supervision way with other known ways of increasing the efficiency of getting information from defined regions shows that the application of the dual-mode method allows to decrease essentially the period of survey frequencies with relatively low economic costs and acceptable power consumption.