Research on ionospheric phase decontamination for OTHR

Ionospheric phase decontamination is a key step to detect ship targets for OTHR. A PGA algorithm based on adaptive clutter filter bandwidth extraction is proposed for small amplitude, slowly varying type phase contamination that can be used to solve clutter filter bandwidth selection. STFT-SPWVD joint time-frequency distribution suppression algorithm is proposed for large amplitude, slowly varying type phase contamination that is with high time-frequency coherence and low cross term. Polynomial phase modeling suppression algorithm based on adaptive order selection, which can quickly and accurately determine the order of the polynomial phase signal, is proposed for small amplitude, fast-changing type phase pollution. STFT-SPWVD and polynomial phase modeling based on adaptive order selection cascaded applications is proposed for large amplitude, fast-changing type phase pollution. The above all algorithms are verified to be effective by the simulation and experimental data.