A High-Accuracy Incoherence Compensation Method for Multiband Fusion Based on Phase-Coherent Coefficient Between Subbands

Multiband fusion (MF) technology can greatly enhance the range resolution of radar by generating ultrawideband echo using several subbands echoes (SBEs). A critical issue of MF is how to accurately estimate and compensate for incoherence between SBEs. In this letter, a novel high-accuracy incoherence compensation method is proposed. First, the phase-coherent coefficient (PCC) is introduced to quantify the phase correlation between SBEs, which is not exactly analyzed in the existing MF methods. Then, it is noticed that for PCC, the linear phase and the fixed phase are coupled and difficult to be estimated simultaneously. Accordingly, this letter proposes to estimate the linear phase and the fixed phase separately, where the linear phase is estimated and compensated by applying the information entropy minimization criterion, and the fixed phase is then compensated based on PCC. Finally, the validity and advantages of the proposed method are investigated by numerous simulation results.