Research On Wireless Communication Filtering Antennas

As two key devices in the wireless communication system,the antenna and filter are the objects to be considered in design of the system.The size and performance of them play an important influence on the wireless communication system.If they are integrated,the performance of the whole circuit system will be improved.Moreover,the size of RF front end can be reduced,and it is easy to integrate with other microwave devices in the system to further realize the integration and miniaturization design of wireless communication system.In the thesis,the integration design of the UWB filter and UWB antenna is studied,and the resonant structure is loaded to complete the design of UWB band-notched antenna.The main work and achievements of this thesis are summarized as follows:Firstly,the research background,significance and the research status of the filtering antenna and the UWB band-notched antenna are briefly introduced.The theory and the main parameters of the antenna are introduced briefly.Secondly,the single band notched UWB filtering antenna is designed,which works from 3 GHz to 10.45 GHz and has good inhibition effect on the signal outside of the UWB frequencies.The WLAN band(5.725 to 5.85 GHz)is notched to avoid the interference of the narrowband communication to the UWB communication.The UWB filter is introduced to the feed end of the UWB antenna.The size of the UWB filtering antenna is smaller than the size of the UWB filter directly cascade with the UWB antenna.At the same time the introduction of the filter does not affect the radiation characteristics of ultra-wideband antenna.Finally,the double band notched UWB filtering antenna is designed,which works from 3.1 to 10.66 GHz,the UWB filtering antenna also has good inhibition effect on the signal outside of the UWB frequencies.At the same time,the stop bands are produced in WLAN(5.15 to 5.35 GHz)and in the X-band(7.9 to 8.4 GHz).The UWB filter based on multimode resonator and UWB antenna are connected by coupling feed.The E-shape structure is placed near the multimode resonator to produce two notched bands.The notched bands can be adjusted by adjusting the size of the E-shape structure.