A Duplexer Synthesis Method Based on LM Optimization Algorithm

In this paper, a method based on LM optimization algorithm is proposed to realize the synthesis of duplexers. The traditional optimization method takes all the variables of the duplexer into account, resulting in too many variables to be optimized when the order of the duplexer is too high, so it is not easy to fall into the local solution. In order to solve this problem, a new optimization strategy is proposed in this paper, that is, two channel filters are optimized separately, which can reduce the number of optimization variables. In addition, this paper synthesizes the filter coupling matrix with complex impedance according to the power waves normalization, and obtains better initial values than direct synthesis. This duplexer synthesis based on this method can achieve higher flexibility in topology structure compared with the traditional synthesis algorithm.