Flexible Wearable Antenna Design And SAR Performance Research

The rapid development of new electronic products attracts people's great interest in the next generation of flexible electronic products,especially mobile communication terminals and wearable electronic products.In recent years,with the widespread use of artificial intelligence products,breakthroughs have been made in the manufacture and development of wearable sensing electronic devices,and the demand for small flexible electronic systems has increased rapidly.Compared with traditional rigid electronic devices,wearable flexible electronic devices have the characteristics of compactness,flexibility,durability and reconfiguration,and have a wider range of application scenarios.Based on the development needs of flexible wearable products applied in wireless communication system,this paper designs wearable antennas with different frequency band widths through structural changes,and designs two flexible wearable composite antennas fed by coplanar waveguides by using two different processing techniques.The flexible composite substrate was fabricated by material doping process,and the performance parameters were improved.This paper focuses on the study of wearable antenna fed by coplanar waveguide.By describing the research background and development trend of flexible wearable antenna and coplanar waveguide antenna at home and abroad,it introduces the feeder principle,basic parameter definition and simulation principle and design method of wearable antenna.Through the use of doping process in polydimethylsiloxane(PDMS)materials doped with different proportions,different types of non-metallic materials to make dielectric substrate,using coaxial dielectric probe detection method to make the doped flexible substrate parameters test,through the analysis of test results for further selection.A novel composite flexible dielectric substrate with high gain and low loss was designed.The structure design and simulation optimization are carried out in the simulation software Ansys HFSS.Two flexible permeable antennas fed by coplanar waveguide are designed and applied in wireless communication system.Through the design of the structure,the band width of the wearable antenna is expanded,and the band of the wearable antenna is respectively(2-6GHz)and(0.99-9.41GHz),covering most of the low-frequency communication band.The specific absorption rate(SAR)simulation test is used to verify the safety of the antenna in human body wearing.In the processing,the use of engraving plotter printing process and metal sputtering process two different processing methods for the surface of the metal structure processing and production.Finally,the antenna was tested for wearable and radiation performance,and its robustness and structural stability were verified by conformal test.The antenna showed good flexibility,stability in fixed frequency band range and good far-field radiation performance,making it an ideal antenna for wearable applications.The two antennas designed by this paper are composed of coplanar waveguide feeding and flexible composite material dielectric substrate,which have good impedance matching characteristics and return loss characteristics within the bandwidth range and are safe for human body wear.In the future wireless communication field and wearable system has a wide range of application scenarios and development potential.