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The electromagnetic fields measured on the ERG satellite are presented and their comparative analysis with measurements on the WIND satellite is carried out. The possibility of capturing auroral kilometric radiation (AKR) into plasma channels, which was first discovered on the ISEE satellite, has been confirmed. Plasma inhomogeneities, formed with an increase in geomagnetic activity, are extended along the magnetic field and form channels along which the radiation propagates. The trapped radiation spectrum is distorted because of the relative position of the source and channel at low frequencies. The distortion of the AKR spectrum at high frequencies is related to the frequency dependence of propagation conditions in the channel. Asymmetry of the processes of formation of plasma channels and AKR sources in the northern and southern auroral regions is found.

According to measurements of the electric component of the electromagnetic field in the frequency range from 2 kHz to 10 MHz by the Japanese ERG satellite, generation regions of kilometric continuum radiation and new hectometric continuum radiation have been determined. It is demonstrated that the kilometric continuum is mainly observed on the dayside of the magnetosphere, its source is located near the geomagnetic equatorial plane, and the size of the source does not exceed ±(0.1–0.3)RE across this plane, where RE is the Earth radius. Hectometric radiation mainly observed in the nightside magnetosphere has two sources. One of them is located near the plasmasphere and its distance from the geomagnetic equator can reach 3RE. The second source is observed near the Earth at distances from 1.1RE to 2RE.

An Erratum to this paper has been published: https://doi.org/10.1134/S0021364022380015

Permanent variation in parameters affecting the key characteristics of the auroral ionosphere hinders the creation of a sufficiently accurate model for practical application within classical approaches describing quasi-stationary phenomena. The fractal approach for describing the properties of plasma in the auroral region has the following advantages: the results are versatile and the emergence of self-similar structures is nature-independent. Due to the self-similarity and fractality of ionospheric structures, it will suffice to have a few measurements within a characteristic scale; therefore, it is necessary to obtain a series of simultaneous measurements at intervals of tens of meters to tens of kilometers to describe the spatial and temporal distribution of inhomogeneities in the ionospheric plasma. Small and relatively low-cost satellites (the socalled cubesats) are supposed to be used to check whether the fractal approach can be applied to study the inhomogeneous structure of the ionosphere, including with artificial heating. The satellites should be located at different distances from each other to span the scales ranging from the inertial length of electrons to the inertial length of O+ ions. For each satellite, it is supposed to measure the variations in plasma density and electric and magnetic fields.

The results of a joint experiment using the Tromso heating facility and the INTERBALL-2 satellite are presented. It is shown that fluxes of accelerated ionospheric electrons reach an altitude of 11200 km, suppressing the auroral kilometric radiation. The timescales of the observed phenomena are estimated and possible physical mechanisms are discussed.

The enhancement of auroral kilometric radiation near its lowest frequency has been detected in the polar edge of the auroral zone in the POLRAD experiment with the INTERBALL-2 satellite. The difference between the local electron cyclotron frequency and the lowest frequency of enhanced radiation is 8–20 kHz, indicating the closeness to the source of auroral kilometric radiation. According to the detailed analysis of low-frequency auroral kilometric radiation, its amplitude is larger than the “background” values by a factor of 20–70 and has amplitude modulation with characteristic periods of 40-60 s. The increase in the intensity at low frequencies is attributed to the intersection of the source region by the satellite and the detection of waveguide modes in it.

A statistical analysis of the auroral kilometric radiation (AKR) measurements in the POLRAD experiment on the INTERBALL-2 satellite has revealed a dependences of the size and location of the AKR generation region on geomagnetic activity: the generation region rises upward and expands with increasing magnetic disturbances. Based on our two-year measurements, we found seasonal AKR intensity variations: the AKR maximum and minimum are observed in winter and summer, respectively. The seasonal variations and the dependence of the spectrum on geomagnetic activity are assumed to have a common physical nature—the background-plasma density variations in the region of the AKR source attributable to plasma flows from the ionosphere into the magnetosphere.