| 摘要: |
| 为了应对低截获概率(Low Probability of Intercept，LPI)雷达通过载频捷变、脉宽随机调制等手段规避反辐射侦察问题，提出了一种基于改进型维格纳分布(Wigner-Ville distribution，WVD)与自适应粒子滤波的波形参数盲估计算法。针对WVD在处理多分量信号时的交叉项干扰，采用时频屏蔽窗口技术进行抑制，提取高置信度的脉冲描述字(Pulse Description Word，PDW)。在此基础上，建立基于隐马尔可夫模型(Hidden Markov Model，HMM)的频率跳变模式预测框架，实现了对波形捷变规律的在线学习与实时跟踪。仿真结果表明，所提算法能够有效解算频率捷变范围超过20%的跳频雷达信号，参数估计精度相比常规自相关算法提升了约15%，能够有效提升反辐射无人机在电子干扰环境下的生存能力与攻击精度。 |
| 关键词: 反辐射无人机 低截获概率（LPI）雷达 波形捷变 盲参数估计 改进型维格纳分布（WVD） 隐马尔可夫模型（HMM） |
| DOI：10.20079/j.issn.1001-893x.260424001 |
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| 基金项目: |
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| Blind Estimation and Tracking of LPI Radar Waveform Agility Parameters |
| CHEN Jie |
| (Southwest China Institute of Electronic Technology，Chengdu 610036，China) |
| Abstract: |
| To address the problem of low probability of intercept(LPI) radar evading anti-radiation reconnaissance through carrier frequency agility，random pulse width modulation，and other means，a blind estimation algorithm for waveform parameters based on improved Wigner-Ville distribution(WVD) and adaptive particle filter is proposed.To mitigate the crossterm interference of WVD when processing multicomponent signals，a time-frequency masking window technique is adopted for suppression，enabling the extraction of high-confidence pulse description word(PDW).On this basis，a frequency hopping pattern prediction framework based on hidden Markov model(HMM) is established，achieving online learning and realtime tracking of waveform agility rules.Simulation results show that the proposed algorithm can effectively process frequency hopping radar signals with a frequency agility range exceeding 20%，and the parameter estimation accuracy is improved by about 15% compared with that of conventional autocorrelation-based algorithms，thus effectively enhancing the survivability and attack accuracy of anti-radiation unmanned aerial vehicle（UAV） in electronic jamming environments. |
| Key words: anti-radiation UAV low probability of intercept(LPI) radar waveform agility blind parameter estimation improved Wigner-Ville distribution(WVD) hidden Markov model(HMM) |
《电讯技术》编辑部 