# Influence of plasma turbulence on microwave propagation

@article{Kohn2016InfluenceOP, title={Influence of plasma turbulence on microwave propagation}, author={Alf Kohn and Eberhard Holzhauer and Jarrod Leddy and Matthew B. Thomas and Roddy G. L. Vann}, journal={Plasma Physics and Controlled Fusion}, year={2016}, volume={58}, pages={105008} }

It is not fully understood how electromagnetic waves propagate through plasma density fluctuations when the size of the fluctuations is comparable with the wavelength of the incident radiation. In this paper, the perturbing effect of a turbulent plasma density layer on a traversing microwave beam is simulated with full-wave simulations. The deterioration of the microwave beam is calculated as a function of the characteristic turbulence structure size, the turbulence amplitude, the depth of the…

## 15 Citations

Microwave beam broadening due to turbulent plasma density fluctuations within the limit of the Born approximation and beyond

- Physics
- 2017

Plasma turbulence, and edge density fluctuations in particular, can under certain conditions broaden the cross-section of injected microwave beams significantly. This can be a severe problem for…

The deteriorating effect of plasma density ﬂuctuations on microwave beam quality

- PhysicsEPJ Web of Conferences
- 2019

Turbulent plasma edge density ﬂuctuations can broaden a traversing microwave beam degrading its quality. This can be a problem for scenarios relying on a high spatial localization of the deposition…

Experimental study of high power mm-waves scattering by plasma turbulence in TCV plasmas

- Physics
- 2017

Understanding the propagation of high power mm-wave in plasmas is of tremendous importance in the route to fusion considering their extensive use in magnetically confined fusion devices. Mm-beams,…

Interaction of radio frequency waves with cylindrical density filaments: scattering and radiation pressure

- PhysicsJournal of Plasma Physics
- 2021

The propagation of radio-frequency (RF) waves in tokamaks can be affected by filamentary structures, or blobs, that are present in the edge plasma and the scrape-off layer. The difference in the…

Millimeter-wave beam scattering by edge-plasma density fluctuations in TCV

- PhysicsPlasma Physics and Controlled Fusion
- 2018

In magnetically confined fusion devices, the use of millimeter waves (mmw) at the electron cyclotron (EC) frequencies ranges from plasma diagnostics to plasma heating, current drive and core…

The effect of density fluctuations on electron cyclotron beam broadening and implications for ITER

- Physics
- 2018

We present state-of-the-art computations of propagation and absorption of electron cyclotron waves, retaining the effects of scattering due to electron density fluctuations. In ITER, injected…

Millimeter-Wave Beam Scattering by Field-Aligned Blobs in Simple Magnetized Toroidal Plasmas.

- PhysicsPhysical review letters
- 2018

A first-principles full-wave model, using conditionally sampled 2D electron density profiles, predicts fluctuations of the millimeter-wave power that are in agreement with experiments.

3D full-wave modelling of microwave interactions with plasma density fluctuations

- Physics
- 2018

The scattering of microwaves by density fluctuations in magnetised plasmas where the
inhomogeneity scale length is comparable to the wavelength is not fully understood.
Yet microwaves are used…

Modelling effects of edge density fluctuations on electron-cyclotron current drive used for neoclassical tearing mode stabilization

- PhysicsJournal of Plasma Physics
- 2021

In this work we study the undesired effects of electron density fluctuations (in the form of blob structures which may exist in the edge region of tokamak plasmas) to the electron-cyclotron wave…

Generation of synthetic magnetized plasma turbulence by representation as a stochastic process

- Physics
- 2017

Plasma turbulence simulations are often computationally expensive with delicate numerical stability. Yet, long simulations are needed to generate uncorrelated turbulence data for studies such as…

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