Antennas Design Of LTE Kids Watch

Smart kids watch is one of the most important categories in wearables industry,phone call and positioning are two major practical applications.Meanwhile data synchronization is necessary with mobile terminals like smart phone.Smart kids watch is also able to get the information of Wi Fi hotpots around for more accurate positioning,NFC mobile payment is another possible useful application.Achieve all above communication functions,possible to use different kinds of small antennas within quite limited space of smart kids watch.This arti cle shows three major small antennas.First,summarized the general requirements for antennas implemented on smart watch also fundamental principles being used.Explained characteristics of different small antennas and methods to improve radiation efficiency,provides the necessary basis for antenna selection and design in subsequent chapters.Then,try to use the external metal loop of smart kids watch as main body of antenna,defined different experimental solutions under the guidance of theoretical analysis,considering feeding and grounding layout,matching circuit optimization and interferences from major electrical components around,finally achieved three expected frequency bands includes LTE B1,LTE B3 and GPS L1.Meanwhile introduced antenna testing system.Finally,studied Wi Fi and Bluetooth PIFA antenna,with design,simulation,measurement and optimization on physical sample,antenna efficiency achieved 27% above.Because design is fixed for NFC chip antenna,only studied on how to improve coupling performance of NFC antenna from matching circuit point of view.This article shows antenna simulation both metal loop and PIFA,measured active parameter TRP,also SAR being tested.Target to improve antenna performance for small antennas implemented on LTE smart kids watch,some optimization methods and design guidelines being summarized.Currently more and more metal casings designed for smart watches,all conclusions are valuable probably.