A normal laser warning system model based on Hadamard transform

摘要

It is very important to extract the useful information from weak laser signal which is obtained in complex battlefield environment as laser warning taking an increasingly important role in laser countermeasures. The weak signal merging in noise becomes difficult to detect since the signal to noise ratio (SNR) of the signal received by the laser warning system is very low in real battlefield. Traditional signal detection methods, in which only mean filter or wiener filter are used; perform poorly in improving the SNR of the signals. A modified matrix of Hadamard Transform based on the Weighting Theory, overcame the disadvantages of matrices that are commonly used to cope with the low SNR signal. The modified matrix generating method of Hadamard Transform is introduced in detail, and then theory analysis, calculations and simulations on the modified matrix Hadamard Transform are presented. The results showed that this kind of Hadamard Transform performs excellently in increasing detection probability and decreasing False Alarm Ratio (FAR) of the laser warning system.