Computational Techniques for Design and Analysis of Time-Varying Capacitor Loaded Transmission Lines Using FDTD and Simulink

In this paper, MATLAB based computational approaches for the design and analysis of time-varying capacitor- loaded transmission lines using the finite-difference time-domain (FDTD) technique and the Simulink design environment are presented. The FDTD formulation for multiple lumped capacitors loaded in series on a transmission line is discussed and extended to include time variation of capacitance. The design methodology for the same is also discussed using MATLAB's Simulink using the RF Blockset Library. The developed FDTD formulation and the Simulink method are then used to design a mixer with time-varying capacitors loaded transmission line.