Wideband Energy Detection Using Weighted Fourier Integral Method With Frequency Color Rendering

The wideband energy detection with conventional beamformer (CBF) is often used for passive target detection. To improve the detection performance, the Fourier integral method (FIM) or weighted FIM (WFIM) may be taken to replace CBF for wideband energy detection. However, for the practical application the target of interest is often submerged in high-level noise and strong interferences, degrading the detection performance of existing methods. In this paper, to improve the performance of passive wideband energy detection, we propose a wideband energy detection using WFIM with frequency color rendering (FCR), which is termed as WFIM-FCR for short. WFIM-FCR assign RGB values to the frequency azimuth (FRAZ) matrix of WFIM, and use color blending to produce the colorful spatial spectrum and the final colorful bearing and time record (BTR). The proposed WFIM-FCR method has two advantages; one is making use of the noise-suppression and high-resolution abilities of WFIM (when compared to CBF); the other is using the frequency distinguishing characteristics (realized by the color rendering) between the target, the interferences, and the background noise. As a result, WFIM-FCR shows a better weak target detection performance than the traditional energy detection. Numerical simulations validate the effectiveness of the proposed WFIM-FCR method.