A Synthesis Technique for Concentric Rings Array Using Sectional Excitation

Many configuration have been used for the array antenna and rectangular or triangular networks have been the most attentive topology. In fact, Synthesis techniques can take the advantage of periodicity of these type of networks. Concentric rings array are a special type of array antennas that are used in tracking radars and acoustic systems. This type of arrays does not have linear periodicity in a plane. Therefore, many methods that are based on the linear periodicity of elements are unable to deal with the difficulty of the calculations. Besides, the number of elements in this type of arrays may be very high or even thousands of elements which makes the synthesis procedure more complicated and time consuming. In this paper, these deficiencies and complexity have been reduced in very great extent by using non-uniform sampling and sectional excitation. In the proposed technique, each array is divided into the smaller sub-arrays making up more control over the symmetric array factor by sectional excitation. This control over array factor makes possible to synthesize asymmetric pattern from such circularly symmetric arrays. The results confirm that using sectional excitation maintains the parameters of the array factor at the desired values and this is done with less time.