OFDM signal with BPSK modulated subcarriers for multi-carrier ionospheric sounding Vladimir Ivanov, Natalya Ryabova, Alexey Elsukov and Alexey Laschevsky ITM Web Conf., 30 (2019) 15006 Published online: 27 November 2019 DOI: 10.1051/itmconf/20193015006