针对低信噪比条件下信号调制盲识别问题,提出了一种基于信号能量聚焦效率检验的识别算法。先对信号进行短时滤波,以提高处理信噪比,后在分析常用6类脉内调制信号单频正弦波生成条件差异的基础上,定义了信号能量聚焦效率特征,并据此实现调制识别。推导了信号能量聚焦效率的统计检验方法。计算机仿真结果表明,本算法在低信噪比条件下可对常用雷达脉内调制方式进行有效识别。
A blind intrapulse modulation recognition based on energy focusing efficiency test was proposed, which can be used to estimate the modulation type under low signal to noise ratio (SNR) conditions. The observed signals were pre- processed by short time filter defined in frequency domain in order to improve the processing SNR. Then, energy focus- ing efficiency feature was defined to identify modulation type of the signals depending on analysis of the condition for the single sinusoid generating among the six types of commonly used intrapulse modulation signals. The statistical test for the energy focusing efficiency was derived. Computer simulation results show that the proposed algorithm can be ef- fective to classify the commonly used intrapluse modulation signals under low SNR conditions.