Coplanar Waveguide Transmission Characteristics Based On The Straight-line Method Limited

Coplanar Waveguide (CPW) is an important planar transmission line, which is developed from the microstrip. With the high-speed development of microwave, millimeter wave and optical integrated circuits, as a new type of integrated media delivery system, CPW has received wide attention. So far, many experts and scholars study on the CPW deeply. Among them, most of researches focus on the CPW of infinite ground-plane width, but when the actual CPW circuits for microwave or microwave devices, its ground-plane width is often finite. Therefore, the accurate analysis of the electromagnetic characteristics of finite ground coplanar waveguide (FG-CPW) is very important. For the above, this paper studies the FG-CPW by use of the method of lines (MoL), and analyzes ground plane width of the impact of change on the electromagnetic characteristics of CPW in detail.In a variety of analysis methods, MoL has aroused a high degree of attention, because of its high-performance solution of partial differential equation. In this paper, the first step is establishment of a solution model for FG-CPW. CPW is a kind of multi-conductor transmission line, and it has many discrete regions and their widths are much difference. So we use nonequidistant discretization to discrete the CPW, because it can greatly reduce the calculation of the matrix, the computing time and memory. In addition, this thesis analyzes the distribution of CPW, including tangential electric field and current distributions of the surface of the conductor, distributions of the electromagnetic field of the whole structure, and so on. According to the results of the field, it obtains the characteristic impedance of CPW. This thesis will make the numerical results by MoL with the literature, simulation and experimental measurements compared to verify the correctness of theoretical analysis. At the same time, it gives the content about the simulation and experimental measurements. According to the theory of MoL, it discusses ground plane width of the impact of change on the electromagnetic characteristics from transmission and dispersion characteristics. Lastly, it shows the calculation software based on MoL, and finishes the precision and efficiency testing. Test results show that the precision of the software can reach the level of the professional simulation software, and this software has the advantage of greater computational efficiency.