The Research Of Microwave Multilayer Circuit By Wave Concept Iterative Process

The electromagnetic (EM) field numerical analysis method, which can analyzes the circuit efficiently and accurately, has been widely used with speed development of microwave circuit. Especially over the recent years, the appearance and application of microwave monolithic integrated circuit (MMIC) and flat plane antenna technique advances a higher analysis speed and accuracy demand for planar circuit and multilayer circuit. Consequently there are important implications for developing a new electromagnetic computational method especially fast algorithm which is with simple theory, fast calculating speed and aim at multilayer circuit.Wave Concept Iterative Process (WCIP), as a neoteric iterative approach, bases on the wave concept, and can work out the microwave circuit discontinuity scattering problem preferably. At the same time, the method has a lower computation complexity. WCIP introduces the incident wave and scattering wave by electric field and current density, builds the recurrence relation between the kth and (k+1)th incident wave and scattering wave. When the superposed waves are constringency, the iterative approach will stop the loop, then, electric field and current density distribution of the circuit interface are achieved. WCIP has been used in single layer microwave planar circuit, but this method is not widely extended to other area at the moment.In this paper, WCIP is introduced to analysis the multilayer microwave planar circuit. The new method combines WCIP with Generalized Transmission Line Theory, analysis the every circuit layer's discontinuity by wave concept, defines the waves between layers by Generalized Transmission Line Theory, and calculates the electromagnetic distribution of every circuit layer by iterated operation, and then acquires the circuit characteristic parameters. Besides, the factors which affect the calculating speed of WCIP are also analysis in this article, the comparison of computation complexity proves the calculating speed advantage of WCIP.In this article, WCIP is used to analysis the multilayer microwave planar circuit such as some microwave antennas which are based on the multilayer circuit. Some circuit characteristic parameters of multilayer circuit antennas are achieved at first, such as electromagnetic distribution, admittance parameter, scattering parameter, VSWR, Gain. Then the simulation results will contrast with Ansoft HFSS's or the reference results, which prove the feasibility that WCIP can analysis the multilayer microwave planar circuit. At last, the computation complexity of WCIP, FEM, MOM is under consideration and comparison, which validates the efficiency of WCIP.