In low-current electronics, the nature of noise was established at the first half of the past century 1. Investigation of noise and fluctuations made it possible to understand spectral lines broadening, amplitude fluctuations, and phase diffusion in physical oscillators, study oscillators' synchronization in detail. However, in relativistic electronics, noise is not studied so well. Despite the fact that the first high-current oscillators appeared in the 70s of the last century 2, only a few works devoted to noisy effects have been published to date 3. In accordance with the published material, the main source of noise in HPM sources is the ecton structure of electron beams produced due to explosive electron emission.
Anishchenko et al. (2023) studied this question.