Distortion detection method for structurally integrated antenna of radar
                                                                          ZHONG Jianfeng1,2, CAI Jianguo3
（1.The 14th Research Institute of CETC, Nanjing 210039,China; 2.National Key Laboratory of Antenna and Microwave Technology, Nanjing 210039,China; 3.School of Civil Engineering ，Southeast University,Nanjing 210018, China)

Abstract: In order to solve the problems that a traditional structure is only used for supporting and force transmitting and the problems that deformation occurred in service due to the coupling between the structure and the outside load, a new type of structurally integrated antenna of radar with a dual function of antenna and loadcarrying capacity was proposed. The deformation detection technology was applied to the structurally integrated antenna, electromechanical coupling model was then constructed and the deformation was compensated. After the analysis of principle and structure of optical fiber, the relationship between the deformation of fiber grating and antenna structure was established.A method was presented to detect the deformation of structurally integrated antenna based on the serial network of triplecore fiber grating sensors. The accuracy of fiber grating measurement was evaluated on the integrated antenna testing system.The comparison of fiber grating measurement and photogrammetry was tested.The experimental results show that the deformation error of the fiber grating measurement, except for a few points, is within 10% error, which is acceptable and can satisfy the antenna performance compensation in the future.

Key words: radar antenna; distortion detection; fiber grating sensors; structurally integrated antenna