Operation analysis of the wideband high-power microwave sources based on the gyromagnetic nonlinear transmission lines

Abstract

The wideband High-Power Microwave (HPM) sources, which combine the advantages of narrowband and ultrawideband sources, have drawn much attention. As a kind of wideband source, the gyromagnetic nonlinear transmission lines (GNLTLs) can directly modulate the incident pulses into radio frequency pulses without relying on the interaction between e-beam and microwaves. Due to the special working mechanism of gyromagnetic precession, the center frequency of the GNLTL can also be adjusted in a certain range. Based on classical magnetism and a simplified model of the GNLTL, this paper semi-quantitatively and theoretically analyzed the generation mechanism of HPM and illustrated the influences of the variations of parameters on the output microwaves. Then, a simple simulation based on 1-dimensional transmission line modeling method was carried out to study the performance of the GNLTL quantitatively, with the coupling of 1D telegraphist equations and the 3D Landau–Lifshitz–Gilbert equation. Simulation results preliminarily verified the conclusions derived from the theoretical analysis, and some working characteristics of the GNLTL were also obtained. This paper may help to understand the special working mechanism of the GNLTL and provide certain guidance for related simulations and experiments.

Computer simulation of multi-gigawatt magnetic compression lines

“…The reason for the appearance of the voltage in addition to the counter-EMF, which is always induced by the main pulse current, is the lag between the movement of M and Heff, which can be described by a divergence angle between these vectors αMH. Modifying the analysis performed in [8] for arbitrary αMH values, and assuming a steady precession of M around Heff with an angular frequency ω, the additional instantaneous induced voltage Vi can be written as (3):…”

“…In literature there are reports on numerical models of GNLTLs, which are usually based on one of the two approaches. Several models [7,8] consider the GNLTL as a transmission line, which can be described by the telegraph equations. The magnetization dynamics is solved using the Landau-Lifshitz-Gilbert equation (LLG) for a magnetized medium.…”

RF generation using a compact bench gyromagnetic line

“…11,12 More recently, there has been a growing interest in this topic because of the use of gyromagnetic lines as RF sources. Since a complex mathematical analysis is required, several recent studies [32][33][34] resorted to addressing this problem using numerical modeling based on Dolan's method, electromagnetic software such as COMSOL, or open-source software well established in the micromagnetic community. 35 In the GNLTL schematic (Fig.…”

Пикосекундный Магнитный Компрессор Гигаваттного Уровня Мощности

“…В течение последних 5 лет ситуация в области генерирования мощных пикосекундных импульсов изменилась кардинальным образом. Оказалось, что гиромагнитная нелинейная передающая линия (Nonlinear Transmission Line, NLTL), содержащая надетые на внутренний электрод ферритовые кольца, намагниченные внешним магнитным полем, в определенных условиях может работать не только как генератор СВЧ колебаний [3][4][5][6][7], но и как усилитель мощности входного видеоимпульса [8][9][10][11][12][13]. Суть подхода, предложенного в [8] и развитого далее в [9], заключается в том, что линия работает в режиме магнитного компрессора энергии (Magnetic Compression Line, MCL), который реализуется при близких значениях длительности входного импульса напряжения и периода колебаний, генерируемых в линии.…”