The Study And Realization Of The Artificial Transmission Line

With the rapid development of wireless communication technology, electronic system performance of microwave circuits have become demanding increasingly. Its type is getting more and more, and new craft and design methods are also emerging. The microstrip circuit becomes a kind of important component because of its unique characteristic, and its related technology has also obtained extensive and in-depth research and considerable development, especially the size of the circuit turns toward miniaturization. Of these, researchers have proposed a planar artificial transmission line which can greatly reduce the size of microwave circuits. On the basis of artificial transmission line in the simulation analysis and theoretical study, Paper presents the experience formula to design artificial transmission line, which laid a good foundation for the wide application of artificial transmission line. Paper is divided into the following sections:First, paper analyze the artificial transmission line using lossless transmission line equivalent circuit, and study the relationship between the structure of planar artificial transmission line parameters and the characteristic impedance, electrical length. And then, using the simulation software, a dual-frequency power divider is designed by the planar artificial transmission line. The measurements show that S-parameters can meet the design requirements, and circuit area reduced by 50% comparing with the traditional Power divide.Secondly, paper focused on theoretical analysis of planar artificial transmission line equivalent lumped circuit. Combining with two-port network of the transfer matrix and scattering matrix, function about the artificial transmission line characteristic impedance and propagation constant is derived. Paper summarized the different circuit dimensions, dielectric constant and dielectric substrate thickness of the empirical formula of artificial transmission line, and use empirical formula to design the plane artificial transmission lines expected which measurements with the expected value, the simulation values have a good consistency, and verify the validity and reliability of the formula. In the end, a single-frequency power divider is designed by the empirical formula. The design process time has been shorted greatly, and the blindness of the design has been avoided. For the widespread using of artificial transmission line laid a good foundation.Next, in order to reduce loss, the structure of discontinuities was modified. Comparing the low-frequency from 0 to 2.5GHz, The loss of simulation results can be reduced significantly. The research method and conclusions provides a useful reference in the low-frequency.Finally, the thesis summarizes the entire work and the future prospect of the relevant research work.