Assessment volume of a forest biomass by the attenuation of the navigation signals the frequencies L1Anatoly Sorokin, Anatoly Ostylovsky, Aleksandr Borisov, Viktor Ivanov, Daniil Makarov and Dmitry KharlamovE3S Web Conf., 149 (2020) 02006DOI: https://doi.org/10.1051/e3sconf/202014902006