Modern studies of solar radio emission are complicated by continuous power amplification and multifrequency external interference, which often completely overlap important frequency ranges. Many topical problems in solar radio astronomy require large effective areas of radio telescopes, high frequency and time resolutions, accurate spatial measurements, and a large dynamic range. It becomes relevant to change the concept of receiving recording equipment. This paper deals with topical problems of the physics of the solar corona in combination with optimal methods of observation with large instruments. The features and difficulties of combining high parameters—dynamic, spatial, temporal, and frequency resolutions—are considered. The proposed solutions of the new-generation observation complex implement the possibilities of intelligent selection of registration conditions in a multioctave mode with multichannel over 8000 channels/GHz with temporary permission up to 8 ms/spectrum. A multiobject observation mode becomes available from powerful flaring objects to faint structures of various nature. High-speed data processing makes it possible to implement an online mode of interference elimination, which is based on a fast statistical analysis of the spectrum with the selection of non-Gaussian (interference) structures. Methods for high-speed analysis of large-volume data (the principal component analysis method) and their presentation to the user are proposed. Examples of the operation of the complex in the range of 1–3 GHz are given. The prospects of a new approach for multiobject radio astronomy observations in the implementation of the RATAN-600 tracking mode are considered: from recombination lines to wide-range spectra, from low-contrast fluctuations to fast changes in flares, etc.

To implement the tracking modes of the RATAN-600 radio telescope, it is necessary to introduce new automation tools that provide a new quality of monitoring and control of the antenna system geometry [1, 2].In this work, the ACS is considered by the movement of the type 3 feed and the carriage, its structure is shown, new capabilities of the complex, previously unavailable on the RATAN-600 radio telescope, are considered.

There is a need today to recreate the Havana observational solar station because of the importance of obtaining a regular forecast of solar activity in a wide range of time intervals. The concept of the created observation network and the infrastructure of the monitoring station as a network element are described in detail. The functions of this network will provide continuous observational material for the Russian Sun and Space Weather Services and will be independent of space observations, but capable of using them for quality control. The physical foundations of complex observations for a wide range of heliogeophysical phenomena are considered.

The paper covers characteristics of big interferometers and reflecting radio telescopes intended for the studies of the solar atmosphere radiation. Solar radio interferometers (radioheliographs) have proven to be more cost-effective than single dish radio telescopes, since using the aperture synthesis allows for fast imaging of the Sun and its active regions with higher spatial resolution, thus, studying solar eruptive processes more efficiently. From the other hand, the studies of many fundamental aspects of the solar atmosphere physics requiring studies of low-contrast structures before and after flares gained no proper development. The efficiency of radio reflectors was enhanced in last decades mainly due to the development of matrix methods of reception, focal arrays, and also due to spectroscopic analysis in the wide wavelength range with high flux density sensitivity. Meanwhile, the diversity of issues related to the physics of the solar atmosphere and active processes requires an optimal combination of capabilities of various microwave interferometric and reflecting systems for joint studies of the Sun. In view of the started implementation of solar observation programs with a new instrument, ALMA, and obtaining newly observed data in the millimeter and submillimeter ranges, the areas of development of solar studies with the RATAN-600 radio telescope in the wide wavelength range are discussed.

Irregular time evolution of the radio emission generated in a B2-class microflare (S0L2017-01-25T10:15), occurring on 2017 January 25 in active region 12,628, is studied. The microflare was apparently initiated by an appearance of an s-shaped loop, observed in the EUV band. The radio emission is associated with the nonthermal electrons detected with Ramaty High Energy Solar Spectroscopic Imager, and originates simultaneously from two opposite footpoints of a magnetic fan structure beginning at a sunspot. According to the active region geometry, the footpoints are situated in the meridional direction, and hence are observed by RATAN-600 simultaneously. The radio emission intensity signal, as well as the left-hand and right-hand circular polarization signals in the low frequency band (3-4 GHz) show good correlation with each other, with the average characteristic time of the variation 1.4 +/- 0.3 s. The polarization signal shows a time variation with the characteristic time of about 0.7 +/- 0.2 s. The irregular quasi-periodic pulsations of the radio emission are likely to be caused by the superposition of the signals generated at the local electron plasma frequencies by the interaction of nonthermal electrons with the plasma at the footpoints. In this scenario, the precipitation rate of the nonthermal electrons at the opposite footpoints could be modulated by the superposition of fundamental and second harmonic modes of sausage oscillations, resulting in the observed different characteristic times of the intensity and polarization signals. However, other mechanisms, e.g., the oscillatory regime of loop coalescence or magnetic null point oscillation could not be rigorously excluded.

We describe two methods of fast condition diagnostics of the reflecting surface of the RATAN-600 radio telescope. The first one is based on a radio holography, and the second one relies on measurements of the random scattered background in the observations of the extended radio sources. Both methods were used in the antenna measurements, which proved the reflecting surface of the of the radio telescope main mirror to be in acceptable condition even after 20 years since the last resurfacing.