BPSK signal shaping and processing for digital SDR ionosonde

The paper presents the algorithms of BPSK signal shaping and processing for vertical incidence ionospheric sounding with the use of a hardware platform USRP which implements SDR technology. The principle “ADC to an antenna”, which provides completely digital processing, allows to apply new algorithms. The developed algorithms allow to obtain a quality images of ionograms with the use of low-power signals (less than 20 W). The algorithm of coherent spectral integration, which causes the increase in the SNR, and the algorithm of narrowband interferences mitigation, which uses median equalization, are presented. The efficiency of the algorithms was verified in the full-scale experiments on vertical incidence ionospheric sounding in Yoshkar-Ola.