Design And Analysis Of Some UWB Antennas

As a key component of the wireless communication system to send and receive signals,the performance of antenna directly determines the communication function of the entire communication system to work well.Ultra-wideband(UWB)wireless communication technology has developed rapidly in high-speed wireless communication,radar tracking,ranging,precise positioning and other fields with high speed and low error rate.It has become the next generation research on Short distance and high rate Commercial Wireless Communication System.However,there are still some problems,such as the interference problem between ultra-wideband systems and narrowband systems(3.3-3.8GHz WiMAX band and 5.15-5.825GHz WLAN band),in order to avoid mutual interference,the UWB antenna need to block these bands,that is notch characteristics.On the other hand,with the rapid development of modern battlefield,the rapid development of modern anti-missile technology,electromagnetic signal transmission and reception of end-launched antenna or array performance determines the anti-radiation missile capture,tracking targets,and directional attack radiation target efficacy.At the same time,the technical requirements for the antenna also put forward higher indicators.Such as high gain,wide 3dB beamwidth,low sidelobe level,very wide frequency bandwidth,small size,simple mounting structure,etc.It has brought great difficulties to the design of the antenna on the anti-radiation missile surface.The use of traditional antenna design techniques to deal with these requirements and difficulties are very challenging.In view of these two practical problems,the main work of this paper is as follows:(1)A wide-band antenna with coplanar waveguide feed and load coupling unit is designed and fabricated.The antenna can meet the requirements of the low-side in UWB communication.The influence on impedance bandwidth with the changing of the key parameters of the antenna is analyzed(2)A compact UWB antenna with coplanar waveguide feed and a U-shaped slot is designed and fabricated.The influence on impedance bandwidth with the changing of the key parameters of the antenna is analyzed.(3)An UWB antenna has the characteristics of single band-notch,two uniform L-shaped slot is symmetrically loaded on the antenna radiating patch of it is designed and fabricated.The antenna can block the WIMAX band and focus on the influence on band-notch characteristics and impedance bandwidth with the changing of the key parameters of the L-shaped slot.(4)An UWB antenna has the characteristics of double band-notch and L-shaped and U-shaped slots are simultaneously loaded on the radiation patch of it is designed and fabricated.The antenna can block both the WLAN and WiMAX bands.We focus on the analysis the influence on the notch characteristics of the antenna with the not evenly changing of the width and length of the etching slot.(5)In view of the characteristics of excellent directivity and high gain of the LPDA,we transform the structure of the original dipole logarithmic antenna array with the actual engineering requirements,and use the surface of the missile as the grounding plate of the antenna.A novel UWB antenna hast the characteristics of biased end shot to meet the actual needs of the missile is designed and fabricated The influence on the impedance matching of the key parameters of the antenna is analyzed and optimized.