TWO-DIMENSIONAL ANALYSIS OF MICROSTRIP CIRCUITS AND ANTENNAE.

This article reviews methods and applications of two-dimensional analysis approach to transmission structures, circuits, resonators and antennae with one of the dimensions much smaller than the operating wavelength. Various methods of analysis discussed include Green's functions approach, segmentation method, desegmentation method, numerical methods for arbitrary shapes, and multimode characterization. Applications in the design of circuits as well as antennae are discussed. Circuit applications include; accurate analysis of MICs, compensation of discontinuities, circuit optimization, design of planar resonators, design of ferrite components, and thin waveguide circuits. Applications to microstrip planar antennae involve modelling of antenna configurations as multiport networks. Specific configurations reviewed include gap-coupled antennae for broadband operations, and optimization of single-feed circularly-polarized microstrip antennae.