An improved mixed-integer multi-objective particle swarm optimization and its application in antenna array design

An improved mixed-integer particle swarm optimization (MI-PSO) algorithm is presented, which is called asynchronous updating particle swarm optimization (AU-PSO). The proposed algorithm speeds up convergence rate of PSO by handling discrete and continuous decision variables differently. The discrete variables have a possibility holding previous values, while the continuous variables are treated normally. This kind of treatment provides more chances to find a better solution. The proposed AU-PSO is then examined by test functions and successfully applied in a design of circular antenna array.