Study On Miniaturization Of Ultra-wideband Antenna

Now,we are fortunate to live in the era of rapid development of technology,and various advanced technologies are constantly emerging,bringing surprises and conveniences to the world.Ultra-wideband communication technology is a new wireless communication technology that has unparalleled advantages over many traditional communication technologies.While as a core part of this technology,the study of ultra-wideband antennas has become more popular in this field.In view of the current development trend of ultra-wideband antennas,ultra-wideband antennas should be characterized by wideband,miniaturization,and easy integration and so on.In addition,the wide operating bandwidth(3.1?10.6GHz)of the UWB system covers the operating band of WLAN(5.15?5.825GHz).In order to avoid interference of WLAN signal to the UWB system,ultra-wideband antennas with band notched characteristics have attracted much attention.The main works of this paper are as follows:Firstly,the development of UWB antenna is explored,including the research significance and development status,then the market demand of miniaturized UWB antenna is put forward.The theoretical research on the microstrip antenna is carried out,which is the key research object to achieve ultra-wideband miniaturized antenna.The principle and method of broadening the band of the microstrip antenna,realizing miniaturization-and band notched characteristics are summarized.Then,an ultra-wideband miniaturized microstrip antenna with simple structure and excellent performance is proposed.Four right angles are cut on the basic rectangular patch,so a gradually changing structure is introduced between the patch and the ground and the frequency band is broaden.In order to further broaden the frequency band,a u-shaped slot is cut at one end of the ground near the radiation patch.The size of the antenna is reduced by cutting the area with low current energy density of the rectangular patch.The cut-out area is a rectangle of 9×8 mm2,and the size of the antenna is successfully reduced.By optimizing several parameters,an ultra-wideband antenna with an impedance bandwidth of 1.5 to 18.7GHz and good omnidirectional radiation characteristics over the entire operating bandwidth is obtained.Next,a new ultra-wideband antenna with band-notched characteristic with CPW-feed is proposed.In order to avoid interference of WLAN signal to the UWB system and achieve the sharp and controllable notch-band characteristic,one pair of half-wave-length stubs and slits are introduced inside the tapered slot and the circular patch,respectively,on the basis of an UWB antenna with good performance.A combination of two processing techniques yields an UWB band-notched antenna with good frequency selectivity.Simulated and measured results show that the antenna has an operating band of 3.0 to 11 GHz,can meet the requirements of the UWB communication system,and it shows a good band-notched characteristic in 5.0?5.8GHz,which can avoid the interference of the WLAN signal effectively.Lastly,the work of the paper is summarized and the expectations for later work are put forward.