Variable Sensing of Large Phased Antenna Array for Spaceborne SAR

The loading of the satellite borne phased array antenna during the orbit is complex. Under the action of multiple loads, the phased array antenna will inevitably have vibration, deformation and other conditions that affect the shape accuracy of the antenna, and then the antenna electrical performance, working reliability and other parameters, and ultimately lead to the decline of the task data product indicators or the task failure. To ensure the normal operation of the antenna under deformation, we usually use mechanical compensation or array electrical compensation to make the electrical performance of the antenna meet the design requirements. However, both compensation methods require us to know the deformation of antenna array. In this paper, the deformation of the whole antenna array is deduced by using the finite strain information of the spaceborne phased array antenna detection points through the modal reconstruction method. Through this mode reconstruction, we can quickly obtain the deformation of the antenna under load and provide input for antenna performance compensation.