Optimization And Design Of Wide-Beam And Wide-Band Yagi Antenna

In this paper, a wide-beam and wide-band Yagi antenna worked in VHF for thedemand of Meteor Burst Communication (MBC) system is studied. The calculationand multi-objective optimization of the Yagi antenna is given by the Method ofMoments (MOM) and an improved hybrid optimization algorithm which incorporatesNelder-Mead Simplex Method into Differential Evolution (DE) algorithm.Aiming at the slow convergence and bad local searching ability of the traditionalDE based on the single strategy, the hybrid optimization algorithm incorporatedNelder-Mead simplex method into DE can improve the convergence speed andsolution precision apparently. In this paper, the hybrid optimization algorithm issuccessfully applied to the optimization of the Yagi antenna.For the MBC, the coverage area of the antenna pattern determines the availablemeteor burst range. Therefore, the beamwidth of the MBC system should be as wide aspossible. But the wide-beam demand will reduce the gain of the antenna and thenmany originally available meteor burst will be abandoned. So the parameters must beoptimized properly.In this paper, the methods to extend the bandwidth are studied in detail bytheoretical analysis and optimization. And several workable methods are proposed tobroaden the beamwidth of Yagi antenna. At last, a Yagi antenna with the22%relativebandwidth and the beam width up to80°is designed and measured and can besuccessfully used in MBC system.