Analyzing Existing Applied Models of the Ionosphere for Calculating Radio Wave Propagation and Possibility of Their Use for Radar Systems. I. Classification of Applied Models and the Main Requirements Imposed on Them for Radar Aids

Abstract

We review modern HF–X band radars covering over-the-horizon problems. The ionosphere significantly affects wave propagation in all the bands. We describe available correction techniques, which use additional evidence on the ionosphere, as well as models of different degrees of complexity. The fact that the field of view cannot be covered by ground-based instruments as well as the growing requirements to the precision and stability of the radars result in the impossibility of ionospheric correction with up-to-date models, hence the latter require further elaboration. We give a virtually full classification of the models. The article summarizes the requirements to the models for the radars depending on their function.

Analyzing Existing Applied Models of the Ionosphere to Calculate Radio Wave Propagation and a Possibility of Their Use for Radar-Tracking Systems. Ii. Domestic Models

“…Development of theoretical, empirical, and semiempirical ionospheric models has been the most important line of ionospheric research. Depending on solar and magnetic activity, season, time of day, geomagnetic latitude, models have been developed of the D-, E-, F1-, F2-regions, E s layer, rarely of the outer ionosphere, as well as of ionospheric disturbances of different nature [Aksenov et al, 2019].…”

“…The above models, as has been noted, are deterministic. By their physical nature, the deterministic models cannot in principle satisfy the following two requirements [Aksenov et al, 2019] 1) consideration of irregular, constantly changing state of the ionosphere (this property of the ionosphere can be satisfied by empirical, semi-empirical or theoretical probabilistic-statistical models);…”

“…The first part of the paper by Aksenov et al [2019] presents a detailed classification of ionospheric models, briefly describes existing methods of considering ionospheric conditions in modern SHF-, UHF-, VHF-, HFband radars, formulates requirements for ionospheric models to use them in radar, which significantly improves radar performance. The purpose of the second part of the research is to analyze domestic models for compliance with these requirements.…”

“…In general, the existing and currently developed ionospheric models (with rare exception) can be used for calculating propagation of only HF waves, i.e. for one-hop over-the-horizon radars [Aksenov et al, 2019].…”

“…3. There is a more or less detailed description of the model that allows us to evaluate it for compliance with the requirements [Aksenov et al, 2019].…”