Research On Image Formation For Bistatic Forward-looking Spaceborne/Missileborne SAR

For missiles,most of the targets are located in front of them,so the missile borne forward looking imaging research is of great practicality.Starting from the characteristics of forward looking imaging,this paper proposes a bistatic forward looking imaging system.Due to the special military role of the missile,a fixed shift mode SAR imaging system with a stationary satellite as a station,a cruise missile or a ballistic missile as a receiving station is proposed,and the system requirements and feasibility of the SAR forward looking imaging are discussed.This paper mainly studies the system modeling and two-dimensional forward looking imaging technology of the spaceborne bistatic SAR.This paper analyzes the system characteristics of the bistatic forward looking system and proposes solutions based on the existing problems.Generally speaking,this paper mainly explores the following points and gives a more innovative method:1)The model building of the spaceborne-missile bistatic forward looking system: according to the limitation of the single base SAR and the operational characteristics of the missile,the double base forward looking configuration with the geostationary satellite as the launching station missile is proposed,and the forward looking geometric model of the missile is constructed,and the two dimensional space variability and the two-dimensional resolution are further deduced and analyzed.Explore the range of parameters that look forward to.2)Discussion on synchronism of the spaceborne-missile bistatic forward looking system: for bistatic system imaging system,how to ensure that echo scattering is received and can be processed correctly,it is necessary to ensure the synchronization of the system.Then the echo model is first established for this kind of spaceborne-missile bistatic forward looking system,and then the composition of the bistatic SAR system and the system synchronization bar are analyzed.3)Research on two dimensional imaging of the spaceborne-missile bistatic forward looking system: the bistatic system mode must be used in the forward looking imaging,while the bistatic system of the spaceborne-missile has its unique superiority,and the complexity of the system is the cost,so there is a complicated space change problem in the forward looking imaging.The bistatic SAR of the spaceborne-missile is built in one station,and the double root number problem of the skew course caused by the two station movement is also avoided,thus simplifying the single root number form.At the same time,due to the existence of the subduction section of the missile,and the existence of acceleration in the subduction section,the error of the distance migration will be greater,and the error of the high phase term can not be ignored.After the analysis,the NLCS algorithm is used to deal with the problems related to the one station fixed bistatic SAR forward looking imaging.The bistatic two-dimensional imaging of the combined spaceborne projectile.