| 摘要: |
| 为了解决高速飞行器通信时的高动态信号捕获问题，根据多普勒变化特点，将信号建模为非线性调频信号，采用时频分析的方式提取瞬时频率，设计了一种基于多重同步压缩(Multisynchro Squeezing Transform,MSST)的时频分析方法，有效提高了时频能量聚集能力和鲁棒性。为了避免时频图起始点选择错误引起的频率估计误差过大的问题，提出了一种分段能量泛函最小化法，将时频面分成多个部分，向前向后分别提取脊线，提高了低信噪比下频率估计的准确性。仿真结果表明，对6玀a、40g、100玤/s的高动态信号，相比传统时频分析方法频率估计精度提高50%以上，所提方法捕获概率可达到95%以上，对低信噪比高动态信号有较强的适应能力。 |
| 关键词: 高动态信号捕获 非线性调频 多重同步压缩(MSST) 分段能量泛函最小化 |
| DOI：10.20079/j.issn.1001-893x.221001004 |
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| 基金项目:国家自然科学青年基金(61805284) |
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| A High Dynamic Signal Acquisition Technology Based on Multisynchro Squeezing Transform(MSST) |
| CHENG Lingfeng,NI Shuyan,CHEN Shimiao,LIAO Yurong |
| (a.Graduate School;b.Department of Electronic and Optical Engineering,Space Engineering University,Beijing 101416,China) |
| Abstract: |
| In order to solve the problem of high dynamic signal acquisition of aerial vehicles with high speed,the signal is modeled as a nonlinear frequency modulation(FM) signal according to the characteristics of Doppler change,and the instantaneous frequency is extracted by time-frequency analysis.A time-frequency analysis method based on Multisynchro Squeezing Transform(MSST) is designed,which effectively improves the time-frequency energy focusing ability and robustness.In order to avoid the problem of excessive frequency estimation error caused by the wrong selection of the starting point of the time-frequency map,a subsection energy functional minimization method is proposed,which divides the time-frequency surface into multiple parts and extracts ridge lines forward and backward respectively,thus improving the accuracy of frequency estimation under low signal-to-noise ratio(SNR).The simulation results show that the frequency estimation accuracy of the proposed method is more than 50% higher than that of the traditional time-frequency analysis method for 8玀a,40g and 100玤/s high dynamic signals,and the acquisition probability can reach more than 95%.The method has strong adaptability to low SNR and high dynamic signals. |
| Key words: high dynamic signal acquisition nonlinear frequency modulation multisynchro squeezing transform(MSST) subsection energy functional minimization |
