Design of non-uniform circular antenna arrays by convex optimization

The design of a non-uniform circular array with the minimum number of antenna elements for a desired sidelobe level (SLL) under the constraint of a fixed beam width is presented. The related synthesis is formulated and relaxed to a convex problem. The convex optimization method is proposed to determine an optimum set of weights and locations of the non-uniform spaced elements based on the minimization of l1-norm. Numerical experiments have been presented to validate the effectiveness and advantages of the proposed synthesis method. Compared with those so-called global optimization algorithms like firefly algorithm (FA), genetic algorithm (GA) and particle swarm optimization (PSO), the proposed method is more robust. Moreover, it can achieve a lower SLL and lead to fewer elements.