Design and analysis of radar antenna structure with optimum dynamic behavior

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2016
Sun, Enver
With the advance of technology the radar antenna structures are being smaller and their design alternatives are quite numerous that they can be produced in different shapes and can be conformed to original structures such as body panel of an aircraft or car which are composed of light weight thin shell structures. Radar antennas as an integral part of the air or ground vehicles are subjected to various dynamic loadings which effects its overall radiation pattern which results overall degradation of antenna performance, especially at high amplitude resonance conditions due to low stiffness of host structures. The passive vibration control, namely surface damping treatment methodology is one of the measurement technique that can be taken account at the initial design phase of such integration process which is based on increasing the damping capacity of host structure by adding viscoelastic materials between contacting surfaces. However adding high density materials results increase of overall weight. Therefore an extensive research activity has been carried out in order to design of surface damping treatment with spacer layer with minimum weight and maximum damping constraints. In this study, for simplicity and to verify the design methodology, a four layer cantilever beam that represents the host structure, was designed, analyzed and tested for optimum dynamic behavior. Mainly topology and parametric optimization methods are used in order to find best material layout of uniform spacer and best slotted configuration of spacer layer that maximize the damping performance of the design with minimum material condition. Experimental study is also conducted for layered cantilever beam with developed concept design of slotted configuration under vibration load to verify the methodology used.

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Citation Formats
E. Sun, “Design and analysis of radar antenna structure with optimum dynamic behavior,” M.S. - Master of Science, Middle East Technical University, 2016.