Fig. 2
![Fig. 2](http://media.springernature.com/full/springer-static/image/art%3A10.1186%2Fs40645-021-00441-8/MediaObjects/40645_2021_441_Fig2_HTML.png)
Signal-to-noise ratio (top) and electron density (bottom) behavior over Kharkiv and Shigaraki during joint measuring campaign on 5–6 September 2017. LT is solar apparent time
Signal-to-noise ratio (top) and electron density (bottom) behavior over Kharkiv and Shigaraki during joint measuring campaign on 5–6 September 2017. LT is solar apparent time