Research On Wide-bandwidth Beam Antenna

Since the twentieth century,wireless positioning and direction finding technology has been widely used in military and civilian area.In order to guarantee the quality of wireless communication,the antenna should has a wide beamwidth in the direction finding and communication of aircraft,missiles,etc.,and the antenna is required to have a sufficient gain in the beamwidth to keep the communication even though the signal is weak.In this paper,we design four wide-beam antennas for practical applications with the theory and design of wide beam antenna.In the third chapter,a conformal wide beam logarithmic period antenna with notch characteristics is designed.The antenna has a notch characteristic in the band of6.2~8GHz by loading a double "U"-shaped slot structure with the U-groove design theory and improved method.Finally,a missile-borne DF antenna array consisting of5 antennas is designed in the base of the antenna.The beamwidth of the antenna array is not less than 120? in the range of 3~6.2GHz and 8~12GHz.The gain is not less than 0dB.In the fourth chapter of the thesis,a wide-beam antennas working in the Ku-band,namely the linear-polarized magneto-polar dipole antenna are designs.The loading of the parasitic patch effectively broadens the beamwidths of the antennas.The beamwidth of the antennas are all not less than 160°,and the gains in the beam range are all not less than-2dB.In the fifth chapter of the thesis designs,two quad-ridge horn antennas that work in SC and X-band are designed respectively.In order to widen the working frequency band of the antenna,this paper use an open ridge structure.At the same time,by optimizing the ridge structure,the beamwidth of the two antennas are not less than130?,and the antenna gain in the beam range are above-2dB and-1dB,respectively.Finally,based on the two antennas in this chapter and the linearly polarized antennas in Chapter 3 of this paper,a missile-borne interference antenna array is formed,and the array antennas meet their respective performance indicators respectively.