Electromagnetic Band Gap Synthesis Using Genetic Algorithms for Mixed Signal Applications

Abstract

A novel electromagnetic band gap (EBG) synthesis method for mixed signal applications is presented. In this method, a genetic algorithm (GA) is utilized as a solution-searching technique. One of the main advantages of the proposed method is an automated design procedure for EBG structures that meet given design specifications. For this purpose, the GA method is combined with multilayer finite-difference method (M-FDM) and dispersion diagram (DD) method. The M-FDM is a circuit-based simulator for computing the Z-parameters of planar structures, while the DD method is a plot of the propagation constant versus frequency. The EBG synthesis method introduced in this paper consists of three main parts namely: 1) GA, which generates populations of EBG structures and evaluates fitness functions using band gap response results from DD; 2) M-FDM, which analyzes the EBG structures generated by the GA and links the analysis results to DD; 3) DD, which calculates band gap frequencies using the EBG structure analysis results from the M-FDM and links the calculated stop band frequencies to the GA for fitness checks. For the verification of the suggested method, EBG structures having various specifications have been designed using the EBG synthesizer tool described in this paper. The designed EBG structures have been modeled and simulated using M-FDM. The EBG structures have also been fabricated and measured in the frequency-domain. The corresponding frequency-domain simulations and measurements have exhibited band gaps as per the design specifications used to synthesize the EBG structures.