Comprehensive Array Antenna Based On Genetic Algorithm

The object functions for synthesis of array antennas usually have the characteristics of multi-parameters, non-differentiable even discontinuities. The optimization of pattern function is non-linear problem. Traditional optimization techniques search for the best solutions using gradients or random searching. Gradient methods of them are efficient, but have disadvantages of getting stuck in local minima, requiring gradients calculations, working only on continuous and differentiable parameters. Methods of random search don't require gradient calculations, but tend to be slow, and susceptible to getting stuck in local minima. Genetic algorithm optimizer is robust global search method, and its research is based on probability, having advantage of no restraint of differentiable and continuities and avoiding getting stuck in local minima.First, the paper introduces the basic concepts, traits and operating principle of genetic algorithm. A program is developed, and its evaluation results are also given.Second, we studied on the application of genetic algorithms in antenna synthesis importantly. In the article, the application of genetic algorithms in low side lobe pattern synthesis is given. The research on shaped beam of array antenna by genetic algorithms is presented. One shaped-beam for array antenna is designed using genetic algorithms, the result is better than Woodward. The stability of the result of genetic algorithms is checked. Then, pattern synthesis for sparse array antenna using genetic algorithms is researched.At last, we researched on conformal patch on the surface of cylinder and the effect of conformal antenna platform on the radiations of patches in different positions. How to get a good feeding for conformal array antenna by genetic algorithms is presented in the end.