Adaptive beamforming based on compressed sensing for HF sky-surface wave radar

The High Frequency (HF) hybrid sky-surface wave radar is a new system radar, based on sky-wave transmitting and surface-wave receiving. However, recently, with the rapid development of inshore tourism and digital device, the appropriate beaches for antennas distribution are lesser and lesser, electromagnetic environment is more and more complex. So it is imperative to find a new way for HF over the horizon (OTH) hybrid mode radar system. This paper introduces elementary composing and operating principle of this hybrid mode radar system and a new adaptive digital beamforming method of HF OTH hybrid mode radar system on the receiving radar station based on compressed sensing (CS) and variable diagonal loading (VDL) methods are proposed. Because of the spatial sparseness of receiving target signals, so fewer element can be adopted to sample receiving signals. And then, the target echo of the absent channels can be restored by the Subspace Pursuit (SP) method of CS theory. Then the new adaptive digital beamforming can use the restored echo signals. Finally, the result of numerical experiment demonstrates the effectiveness of the proposed arithmetic.