Effects of Ionospheric Total Electron Content on Direct Path Interference Removal for Single-Channel Passive Radar

Passive radar sounding is a promising remote sensing technique that uses ambient radio emissions as signals of opportunity for terrestrial and planetary radar observations. Recent work has focused on improving passive sounding’s signal-to-noise ratio (SNR) by optimizing a single-channel direct signal suppression (DSS) algorithm to remove direct path interference. However, this technique requires an accurate estimate of the echo delay time, which can be significantly impacted by the ionosphere’s total electron content (TEC). This research adapts a recently developed DSS technique to consider the effects of the ionosphere’s TEC with respect to the echo delay time to provide further improvements to passive radar SNR.