Nonlinear Transmission Line Characteristics And Applications Of Research

Nonlinear transmission lines (NLTLs) are periodic structures,in which nonlinearities are introduced to provide turnable features for controlling the signal propagation characteristics along the line. In this thesis, the historical development and future trend of NLTL are introduced and the characteristics of NLTL are discussed in detail. Based on these theories, applications of NLTL are analyzed and designed.The voltage dependent capacitance of the reverse biased varactors in NLTLs results in voltage dependent propagation velocity which can be used to sharpen the rising edge of a pulse. So NLTL can be used as ultrashort pulse generator to generate sub-picosecond pulse. In this thesis NLTL are used to generate a pair of symmetric positive and negative impulses which are applied in the sampling circuit.The voltage dependent phase velocity in NLTLs also makes them candidate for wideband true time delay lines.A nonlinear delay line is designed in this thesis,and dynamic matching is used for improving the return loss at the input port.NLTLs contain nonlinear components hence can be used for frequency conversion. Second harmonic generation are achieved in this thesis and a modified construction is used for high conversion efficiency.NLTL supports soliton generation and transmission because of containing both nonlinear and dispersive effects. As an important branch of nonlinear science,soliton has important theoretical and applied significance.In this thesis the solitary wave equation is derived and the characteristics of solitons are studied.Until now, few research achievements on NLTL are reported in China. This assignment design of NLTLs may be a practical reference for study and development in future.