New two-color cancellation algorithm for counter-countermeasures of infrared seekers

Abstract

We propose a new two-color cancellation algorithm as an infrared (IR) counter-countermeasure technique for efficient target tracking under IR countermeasures, such as flares. For the proposed algorithm, we use two different spectral bands in the middle and near IR regions and define the ratio between the two bands' signal (MNR) to estimate the spectral distribution characteristics of the target and the flare. The proposed algorithm computes the MNR of the band signals, detects the MNR of the flare (MNRF) from the MNR histogram, and then cancels the flare signal from the middle band signal using the MNRF. We simulate the MNRF detection and the target signal extraction for the performance evaluation. The simulation results confirm that the proposed algorithm can cancel efficiently the effect of IR countermeasures under various conditions. Particularly, unlike conventional algorithms, the proposed algorithm can extract very well the target signal even when the target and flare signals are mixed in time domain. In addition, it is applicable to any ever-changing environment. (C) 2001 society of Photo-Optical Instrumentation Engineers.