Research On Stretchable Antenna Based On Kirigami Structure

In recent years,flexible electronic devices which can be stretched will be widely used in the fields of health monitoring and different sorts of smart wearable devices.As an important part of stretchable devices,stretchable antenna is obtaining increasingly research attraction.Stretchable antennas should maintain the normal performances while they are in bending and stretching situation.In this thesis,four stretchable antennas are designed based on Kirigami structure.Bending and stretching might be easily accomplished in ordinary metal patch of antenna while adopting Kirigami structures.The main work content and research results of this paper are as follows:1.There stretchable monopole antennas have been designed to achieve bending and stretching performances based on Kirigami structures.The Kirigami structures including folding,grid and rhombus grid are applied in antennas respectively.The stretchable anten na with folding structure works at the frequency of 1.66 GHz with bandwidth of 300 MHz.It can be stretched up to 40% along its longitude direction with its resonant frequency shifting to lower frequency and bandwidth is reduced by 33.3%.The stretchable antenna with grid structure works at the frequency of 1.53 GHz with bandwidth of 200 MHz.It can be stretched up to 40% along its longitude direction with its resonant frequency shifting to lower frequency and bandwidth is reduced by 30%.The stretchable an tenna with rhombus grid structure works at the frequency of 1.72 GHz with bandwidth of 340 MHz.It can be stretched up to 30% along its longitude direction with its resonant frequency shifting to lower frequency and bandwidth is reduced by 41.2%.The experiments results reveal that the above three types of antennas with Kirigami structure can not only realize bending and stretching but maintain the antenna's performances while stretching.2.Kirigami structures are adopted in patch antenna which has large areas of metal ground and radiation patch in order to make them stretchable.The transmission lines have been prepared to verify the properties of stretchable ground.Test results exhibited that the performances of the transmission line deteriorate as the microstrips and the ground stretching due to the opening of Kirigami structures.In this case,the ground metal split out and could not cover the whole substrate.To improve the performances of transmission line,two layers metal with Kirigami structures were designed and the interlaced splits on two layers were placed.The designed two layers Kirigami structures were then used in stretchable patch antennas.The test results show that the antenna with two-layer Kirigami structures can be stretched up to 10% along its longitude direction.The resonant frequency of stretchable antenna deviated about 21.1%and bandwidth increased 100% while antenna stretching.