Research And Design Of Wearable UWB Filtering Antenna

With the spring up of wireless communication equipment,especially the intelligent terminal equipment,there is an increasing high demand for the short distance high speed data transmission,portable and miniaturized electronic device.As the important components of communications system,antenna and filter affect the performance of the wireless communication facility,so the study on ultra wideband filtering antenna and wearable filtering antenna is of important significance.This paper focuses on topic of the ultra wideband filtering antenna and wearable filtering antenna,the main research contents are as follows:First of all,the paper described the research background and significance of the filtering antenna and the wearable antenna,and introduced the design features of the wearable antenna and its design requirements.It introduced the basic theories of the filter design and the wearable antenna design,and the methods to add notch-band characteristics on ultra wideband antenna.Then,the low-pass characteristic of the dumbbell-shaped defected ground structure is studied,and an ultra wideband filtering antenna with excellent out-off-band suppression and frequency selectivity is designed.And on this basis it realized notch-band characteristics within passband by etching slot on the feeding line,then an ultra wideband filtering antenna with notch-band characteristics is proposed.Next,a narrowband wearable filtering antenna is designed.A short-stub loaded resonator is used to build a band-pass filter,and the filter is employed in the design of filtering antenna,then the narrowband filtering antenna is designed.Finally,we studied the antenna radiation property under different bending degree,and found that the antenna can still maintain normal operation when the degree of bend is in a certain degree.And then,based on stepped impedance resonator and CPW feed ultra wideband antenna,a wearable ultra wideband filtering antenna is designed.The antenna has good upper stopband characteristic and suppresses the high frequency radiation effectively by allocating these resonant frequencies properly.We analyzed the performance parameters of the antenna under bending,which proved it can withstand certain degree of bend and apply to wearable application.At last,in order to reduce the antenna radiation to human body,electromagnetic band gap structure is proposed.The simulation comparisons of specific absorption rate and radiation pattern are implemented by establishing human models,and verify that the EBG structure can reduce the radiation to the back of the antenna,decrease SAR value and increase antenna gain.