Investigation Of Microwave Discontinuities And Development Of Its Database

Planar transmission line discontinuity problem is an important brunch of microwave theory. The existence of discontinuity seriously affect the characteristic of transmission line. The purpose of this paper is to simulate and study these effect by using computational electromagnetic method, sum up the law based on a large number of numerical experiment and establish a database concerning with the discontinuity problem, which look forward to guiding the engineering design to a certain degree, and reducing the time consuming of EM software simulation or optimization.In this paper, fundamental theory of transmission line, microwave net and finite difference time domain algorithm are briefly introduced first. Then investigation of planar transmission line discontinuities are carried out by FDTD method. These works include exploring the methods of calculating the impedance of non-TEM transmission line, analyzing the characteristic of step discontinuities, validating their compensations and studying the characteristic of microstrip-slotline transitions.As the major work of the research, a database concerning the microwave discontinuities software are established based on the FDTD algorithm. This database covered the common discontinuity problems, such as single discontinuities analyzing and their compensation, transitions analyzing and multi-discontinuities cascading. The database can be updated by fill or delete the data according to the user's intention. In the investigation of discontinuities, this database possess a complete analyzing system including data inquiring, numerical calculating, equivalent circuit simplifying and matrix computing. Meanwhile, in order to easily extend the database and increase the efficiency of establishing 3D model, a function called quick 3D modeling is developed. The amount of work will be cut down and the time consuming will be reduced if the database apply in the research of planar transmission line discontinuities. Finally the reliability of data is tested as well.