Several Reflector/array Studies And Designs

With the rapid development of modern microwave technology,the requirements for high-frequency and high-speed data transmission in applications such as radar and communications have prompted the development of antenna research in the direction of high gain,large bandwidth,and beamforming.Combining the requirements of the subject and actual engineering needs,this thesis mainly studies the following work:First,design a Cassegrain antenna that achieves beam deflection at a specific angle,with a working frequency of 94 GHz and a beam deflection of 5.9°.Through theoretical analysis,discuss the feasibility of its design;then simulate and optimize the design of the standard Cassegrain antenna;then conduct a comparative study of deflection methods,and finally select the off-axis Cassegrain antenna scheme of the secondary surface.Both the simulation and actual measurement results show that the scheme can better achieve the required beam deflection angle and meet other design requirements.Secondly,a shaped single reflector design method for realizing the specified off-axis angular cone beam is given.The method uses the principle of geometric optics to track the beam's forward direction and derives the differential equation that the shaped reflector cross section needs to meet.Solve the shaping curve by numerical algorithm.To meet the requirements of the cone beam,the feed uses an omnidirectional TEM mode horn antenna.According to this method,the design and manufacture of a shaped reflector antenna with a working frequency of 35 GHz and a cone beam off-axis angle of 40° has been completed.The actual measurement results show that the antenna has achieved the required indicators well.This design method can achieve flexible off-axis angle requirements and cone beams with a gain greater than 10 dBi,and has good engineering application value.Finally,a dual-polarization planar reflector array antenna is designed,the working frequency is X-band,and its design highlight is that it can achieve dual-polarization and broadband characteristics.The array adopts dual resonant units to achieve better bandwidth expansion.The phase curve of this unit has better smoothness and phase range.The array design is based on the basic principle of phase compensation,and the dual-polarized quad-ridge horn antenna is used as the feed,The array antenna can achieve a gain of up to20 dBi,a 3dB gain bandwidth of up to 32%,and a good dual-polarization effect,which better meets the design requirements.