Robust multicomponent LFM signals synthesis algorithm based on masked ambiguity function

Wigner distribution (WD) based multiple components linear frequency modulation (LFM) signal synthesis method (SSM) is often adversely affected by cross-terms. Masked WD (MWD) is one of the widely used cross-term suppression techniques in practice due to its simplicity and efficiency. However, the cross-terms are hardly masked out when auto-terms and cross-terms are overlapped (Case I) or the components are very close to each other in the time-frequency (TF) plane (Case II). To solve these problems, we present a robust ambiguity function (AF) based approach for multicomponent signals synthesis. This algorithm consists of two stages. First, a SSM from the AF is proposed according to matrix rearrangement and eigenvalue decomposition. However, the existence of cross-term makes the signal synthesis entirely erroneous. To settle this issue, we present a masked AF (MAF) algorithm based on Radon and its inverse transforms in the second stage. Applying the presented algorithm, multicomponent signals can be synthesized efficiently even in Case I and Case II. Simulation results demonstrate the effectiveness and feasibility of the proposed algorithm.