Adaptive HF Signal Detection Algorithm CFAR and Its Verification By Means of SDR Based Digital Ionosonde with USRP Platform

The paper presents the findings of the research into the problem of automatic detection of signal contaminated with nonhomogeneous noise and interferences for the purpose of sounding of ionosphere and HF communication multi-channel. The use of fixed threshold detector is not appropriate in this case. Thus, we studied two modifications (CA-CFAR, OS-CFAR) of adaptive threshold detection also referred as constant false alarm rate detection which utilizes changing threshold where the threshold level is raised and lowered depending on noise and interferences power in a HF communication channel.