Antenna arrays with shaped power patterns have many applications in communications and radars. Many antenna array synthesis techniques for shaped patterns have been developed in the past years, and most of them deal only with uniformly spaced arrays. In this paper, a new method is proposed for the synthesis of nonuniform linear antenna arrays with shaped power patterns. The proposed synthesis method consists of three steps. First, we find a satisfactory power pattern for the required radiation characteristics by solving a constrained least-squares problem which is obtained with the help of non-redundant representation of squared magnitude of a linear array factor. Then, we factorize the polynomial associated with the power pattern by using polynomial rooting, and consequently obtain the corresponding field patterns. Finally, the forward-backward matrix pencil method is used to obtain a nonuniform linear array with optimized excitation magnitudes, phases and locations for a specific choice of field patterns. The synthesized array has a smaller number of elements than the one with uniformly spaced elements for the same pattern performance. Several synthesis experiments are conducted to validate the effectiveness and advantages of the proposed synthesis method.
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