Study Of Shaped Beam Pattern With Series-fed Microstrip Arrays

Microstrip antenna’s benefits include light weight,low section plane,a variety ofthe electrical properties and so on.It is suitable for large-scale production for easyintegration with active devices and circuit.Antenna arrays can improve the antennagain.And it also can achieve expectable antenna pattern in arrays by beam-formingtechnology and improve antenna’s directivity.A series-fed microstrip arrays with shapedbeam pattern is studied in this paper,it has pencil beams in horizontal direction andcsc2θ shaped beam in pitch direction so it will find its important applications in.thelow altitude and hedgehopping defense radar.In the first part of this paper,a kind of series-fed microstrip antenna element hasbeen designed.Considering of project requirement and design difficulties,the series-fedbilayer dielectric plate rectangular microstrip antenna has been chosen.With a view tothe influence of discontinuity,the equivalent model of series-fed microstrip element hasbeen built,the equivalent parameters has been determined by simulation methods.Secondly,pattern synthesis method of microstrip arrays is presented. A csc2θshaped beam in the pitch direction is carried out with both the technique for powerpattern synthesis proposed by Orchard et al. and the technique for modifiedsin π z π zpattern synthesis combine.The amplitude of the feed of subarray in horizontaldirection is determined by Taylor line source synthesis method.The obtained antennapattern meets the technical requirements.In the last,part of this paper,designment and simulation of a discontinuousseries-fed microstrip rectangular arrays and waveguide feed network is presented.Theantenna is manufactured and the measured results completely fulfills the designrequirements which prove the simulation method in this paper is correct.