Weak target detection based on the Membership Degree of the IMFs Energy

In the paper, the proportions of the sea clutter Intrinsic Mode Functions (ab. IMFs) energy to the whole signal energy and the influence of the target on the proportions are discussed. It is found that the latter low frequency IMFs are weaker when no target is hit, but they are stronger when the target is hit, and the proportions of their energy to the whole signal energy become larger, which could be described by the Membership Degree of the IMFs Energy (ab. MDIE). So the MDIE is proposed to detect the weak target, whose performance to detect the slowly fluctuant target in the sea clutter is better than the one of the weak target detection method directly using the box dimension.