Simulation Studies of Distributed Nonlinear Gyromagnetic Lines Based on <italic>LC</italic> Lumped Model

Abstract

Great interest has been devoted to the study of nonlinear transmission lines (NLTLs) for radio-frequency generation. The two better known configurations of NLTLs are a dispersive line consisting of sections with nonlinear components and a continuous nondispersive line called gyromagnetic line. The goal of this paper is to study the gyromagnetic line through the effects of changing the NLTL parameters. This is done based on an analytical model supported by SPICE circuit simulations and validation of results with numerical analysis, focusing on the pulse rise time compression. Different models are studied by comparing simulations with corresponding results found in the literature. Such a technique could be used for the design of NLTL for space applications and mobile defense platforms of compact size.

Analysis of nonlinear gyromagnetic line operation using LLG equation

“…Nowadays gyromagnetic nonlinear transmission lines (NLTL) have been studied with great interest [1] since they can generate RF up to frequencies of 1-3 GHz at high power (hundreds of MW) as demonstrated recently [2][3][4]. As they are all solid-sate they can be used as compact RF sources.…”

Optimized analysis of sharpening characteristics of a compact RF pulse source based on a gyro-magnetic nonlinear transmission line for ultrawideband electromagnetic pulse application

“…The circuit model proposed by Dolan and Bolton is considered as the optimal method to describe the modulated process of a GNLTL with an azimuthal and an axial biasing field [21]. In order to simplify this model, the instantaneous voltage source is replaced with the nonlinear inductor in the circuit model, the rationality of which has been confirmed [13]. The sharpening effect of a GNLTL can be explained by the 'pursuing theory' resulting from a nonlinear inductor.…”

“…A gyro-magnetic nonlinear transmission line (GNLTL) is a solid-state microwave oscillator, which not only sharpens the rise time of an incident pulse into sub-nanosecond scale, but simultaneously modulates into a certain frequency of RF electromagnetic pulse ranging from hundreds of MHz to several GHz with a kHz repetition rate or even higher by gyro-magnetic precession of a material's magnetic moments [13,14]. Compared with other types of nonlinear transmission lines, GNLTLs can more efficiently generate an RF pulse with a higher frequency and a higher power as a result of the lower dielectric loss and the coaxial configuration with distributed parameters [15].…”

A Review of Nonlinear Transmission Line System Design

“…Several models were used with various parameters: Weiner and Silber's model, a simplified theory on pulse sharpening, had an input of 6 kV and 40 ns rise and fall times; Pouladian-Kari et al's model, which calculated the reduction of the output rise time due to the decrease in permeability, had an input of 12 kV and a 3.5 ns rise time; and Dolan and Bolton's model had an input of -10 kV with a rise time of 2 ns and produced 5 GHz oscillations. The numerical analysis was done using Mathematica [101].…”