On The Conical Conformal Arrays And Antennas Used In Special Fields

The research works are made with scientific projects. The design methods of theconical conformal array and antennas used in special field are discussed in thisdissertation.In the dissertation, the major works can be divided into three parts: the study ofconical conformal arrays with axial main beam and conical conformal phased array aremade in the first part. The engineering samples of several antennas used in special fieldsare proposed in the second part, which includes wideband tapered slot antennas withbroad beamwidth, high gain and special beam microstrip array antennas andsidelobe-suppressed arrays antenna based on elements rotation technique. The author'smajor contributions are outlined as follow:1. In the study of conical conformal arrays, in attempt to axially orient the mainbeam of the array, a projection principle is proposed to manage the polarizationorientation of each element. Then, a 64-element conical conformal array is analyzed viaHFSS to validate the efficiency of the proposed method. In addition, the effects of mainparameters on the array pattern are also discussed.2. In the design of conical conformal phased array, different element arrangementson the conical platform are analyzed to determine the optimum elements arrangement.Then, a 384-element conical conformal phased array is proposed, which employs thedual polarized microstrip patch antennas as the elements of the array. The modifiedBernstein polynomial and the self-adaptive differential evolution algorithm are utilizedto explore the optimum excitation amplitudes distribution for synthesizing the scanningbeam of conical conformal phased array, which has a beam scanning range of 0°~360°in the azimuth, and -40°~40°in the elevation.3. In the design of wideband tapered slot antennas with broad beamwidths, threewideband linearly tapered slot antennas with broad beamwidths based on loadingtechniques are proposed?Measured results illustrate that the proposed antennas couldradiate broad beams in the wide bandwidths.4. High gain and special beam microstrip array antennas are designed andimplemented. To meet the needs of communication systems used in the unmanned aerialvehicle and point to point wireless communication, microstrip array antennas with highgains and special radiation beams are designed via the software Ansoft HFSS,respectively. The proposed array antennas are fabricated and measured. The measured results show that the proposed array antennas can meet the requirements for practicalapplications.5. In the investigation of sidelobe-suppressed array antenna based on elementsrotation technique, a uniformly excited planar microstrip array antenna isselected as an example to analyze and study the principles and features of elementsrotation technique whose advantages and disadvantages are also discussed. Then, awideband array antenna with suppressed sidelobes is proposed. By optimizing theelements spacing and rotation angles, the sidelobes are suppressed in a bandwidth of42%.