A static approach method method is used to get the spectrum expression of the pulse interval modulation signal.The expression is simple,has a clear physical concept and it has been confirmed by a simultaneous experiment.
Pulse repetition interval(PRI)modulation recognition and pulse sequence search are significant for effective electronic support measures.In modern electromagnetic environments,different types of inter-pulse slide rada...Pulse repetition interval(PRI)modulation recognition and pulse sequence search are significant for effective electronic support measures.In modern electromagnetic environments,different types of inter-pulse slide radars are highly confusing.There are few available training samples in practical situations,which leads to a low recognition accuracy and poor search effect of the pulse sequence.In this paper,an approach based on bi-directional long short-term memory(BiLSTM)networks and the temporal correlation algorithm for PRI modulation recognition and sequence search under the small sample prerequisite is proposed.The simulation results demonstrate that the proposed algorithm can recognize unilinear,bilinear,sawtooth,and sinusoidal PRI modulation types with 91.43% accuracy and complete the pulse sequence search with 30% missing pulses and 50% spurious pulses under the small sample prerequisite.展开更多
Recognition of pulse repetition interval(PRI)modulation is a fundamental task in the interpretation of radar intentions.However,the existing PRI modulation recognition methods mainly focus on single-label classificati...Recognition of pulse repetition interval(PRI)modulation is a fundamental task in the interpretation of radar intentions.However,the existing PRI modulation recognition methods mainly focus on single-label classification of PRI sequences.The prerequisite for the effectiveness of these methods is that the PRI sequences are perfectly divided according to different modulation types before identification,while the actual situation is that radar pulses reach the receiver continuously,and there is no completely reliable method to achieve this division in the case of non-cooperative reception.Based on the above actual needs,this paper implements an algorithm based on the recurrence plot technique and the multi-target detection model,which does not need to divide the PRI sequence in advance.Compared with the sliding window method,it can more effectively realize the recognition of the dynamically varying PRI mo dulation.展开更多
开展脉冲重复间隔(Pulse Repetition Interval,PRI)模式识别工作是电子支援系统的一项重要任务。现代复杂电磁环境下,受雷达辐射源部署和接收设备本身影响,雷达脉冲丢失率极高,导致分选后PRI序列调制规律被破坏,现有的PRI模式识别方法...开展脉冲重复间隔(Pulse Repetition Interval,PRI)模式识别工作是电子支援系统的一项重要任务。现代复杂电磁环境下,受雷达辐射源部署和接收设备本身影响,雷达脉冲丢失率极高,导致分选后PRI序列调制规律被破坏,现有的PRI模式识别方法准确率不足。针对上述问题,从PRI序列还原角度出发,并结合PRI序列本质是时序序列的特点,提出GAIN-LSTM(Generative Adversarial Imputation Nets and Long Short Term Memory)网络架构,其先对丢失脉冲位置进行补全操作,恢复PRI调制规律,然后对还原后PRI序列进行调制模式识别。仿真结果表明,提出的GAIN-LSTM网络架构在脉冲丢失率70%时仍保持95%的正确识别率。展开更多
为提升对雷达脉冲重复间隔(pulse repetition interval,PRI)的分析性能,提出了一种基于周期样本图重构的雷达PRI调制类型识别算法。首先,建立了雷达PRI调制模型,分析了不同调制类型的信号特点;其次,利用到达时间(time of arrival,TOA)...为提升对雷达脉冲重复间隔(pulse repetition interval,PRI)的分析性能,提出了一种基于周期样本图重构的雷达PRI调制类型识别算法。首先,建立了雷达PRI调制模型,分析了不同调制类型的信号特点;其次,利用到达时间(time of arrival,TOA)多阶差分序列估计了雷达PRI调制周期,并基于直方图算法重构了PRI周期样本图;然后,以PRI周期样本图为基础,提出了5个PRI调制特征实现PRI调制类型识别;该方法不仅能够提升PRI调制类型的识别准确率,而且对干扰脉冲特别是脉冲丢失具有很强的稳健性;最后,仿真实验表明了所提方法的有效性。展开更多
该文以三相电压型脉宽调制(pulse width modulation,PWM)整流器为研究对象,提出一种基于新型开关表的直接功率控制(direct power control,DPC)策略。首先,根据两相旋转dq坐标系下整流器数学模型计算开关矢量对有功功率和无功功率的控制...该文以三相电压型脉宽调制(pulse width modulation,PWM)整流器为研究对象,提出一种基于新型开关表的直接功率控制(direct power control,DPC)策略。首先,根据两相旋转dq坐标系下整流器数学模型计算开关矢量对有功功率和无功功率的控制幅度,并归一化处理进行定量分析,以此为基础将传统DPC的12扇区重新划分为24扇区。然后,设计有功功率差值区间判断器,根据其输出值Cp和有功功率与无功功率滞环比较器的输出值Sp、Sq,选择当前扇区最佳开关矢量构造新型开关表,实现对有功功率的精确控制。仿真对比表明,该新型开关表不仅克服传统开关表对无功功率控制能力差的缺点,而且改善网侧电流总谐波失真,降低输出直流电压波动和有功功率与无功功率脉动。最后,搭建一台800W三相电压型PWM整流器样机,通过对比实验验证所提控制策略的正确性和有效性。展开更多
遥传技术是随钻测量(MWD,measurement while drilling)系统中的一项关键技术,目前大多数MWD系统均采用泥浆脉冲方式进行数据传输。随着井深的增加,单纯的脉冲调制的传输性能会快速恶化。提出了一种联合卷积编码与脉冲间隔调制,构造出一...遥传技术是随钻测量(MWD,measurement while drilling)系统中的一项关键技术,目前大多数MWD系统均采用泥浆脉冲方式进行数据传输。随着井深的增加,单纯的脉冲调制的传输性能会快速恶化。提出了一种联合卷积编码与脉冲间隔调制,构造出一种网格编码脉冲间隔调制(TC-PIM)方法。TC-PIM最大化调制输出序列之间的最小时间距离,从而获得显著的编码增益。TC-PIM可以用于随钻测量系统,以提高泥浆脉冲遥传系统的传输距离。展开更多
文摘A static approach method method is used to get the spectrum expression of the pulse interval modulation signal.The expression is simple,has a clear physical concept and it has been confirmed by a simultaneous experiment.
基金supported by the National Natural Science Foundation of China(61801143,61971155)the National Natural Science Foundation of Heilongjiang Province(LH2020F019).
文摘Pulse repetition interval(PRI)modulation recognition and pulse sequence search are significant for effective electronic support measures.In modern electromagnetic environments,different types of inter-pulse slide radars are highly confusing.There are few available training samples in practical situations,which leads to a low recognition accuracy and poor search effect of the pulse sequence.In this paper,an approach based on bi-directional long short-term memory(BiLSTM)networks and the temporal correlation algorithm for PRI modulation recognition and sequence search under the small sample prerequisite is proposed.The simulation results demonstrate that the proposed algorithm can recognize unilinear,bilinear,sawtooth,and sinusoidal PRI modulation types with 91.43% accuracy and complete the pulse sequence search with 30% missing pulses and 50% spurious pulses under the small sample prerequisite.
基金supported by the National Defense Science and Technology Outstanding Youth Science Fund Project(2018-JCJQ-ZQ-023)the Hunan Provincial Natural Science Foundation of Innovation Research Group Project(2019JJ10004)。
文摘Recognition of pulse repetition interval(PRI)modulation is a fundamental task in the interpretation of radar intentions.However,the existing PRI modulation recognition methods mainly focus on single-label classification of PRI sequences.The prerequisite for the effectiveness of these methods is that the PRI sequences are perfectly divided according to different modulation types before identification,while the actual situation is that radar pulses reach the receiver continuously,and there is no completely reliable method to achieve this division in the case of non-cooperative reception.Based on the above actual needs,this paper implements an algorithm based on the recurrence plot technique and the multi-target detection model,which does not need to divide the PRI sequence in advance.Compared with the sliding window method,it can more effectively realize the recognition of the dynamically varying PRI mo dulation.
文摘开展脉冲重复间隔(Pulse Repetition Interval,PRI)模式识别工作是电子支援系统的一项重要任务。现代复杂电磁环境下,受雷达辐射源部署和接收设备本身影响,雷达脉冲丢失率极高,导致分选后PRI序列调制规律被破坏,现有的PRI模式识别方法准确率不足。针对上述问题,从PRI序列还原角度出发,并结合PRI序列本质是时序序列的特点,提出GAIN-LSTM(Generative Adversarial Imputation Nets and Long Short Term Memory)网络架构,其先对丢失脉冲位置进行补全操作,恢复PRI调制规律,然后对还原后PRI序列进行调制模式识别。仿真结果表明,提出的GAIN-LSTM网络架构在脉冲丢失率70%时仍保持95%的正确识别率。
文摘为提升对雷达脉冲重复间隔(pulse repetition interval,PRI)的分析性能,提出了一种基于周期样本图重构的雷达PRI调制类型识别算法。首先,建立了雷达PRI调制模型,分析了不同调制类型的信号特点;其次,利用到达时间(time of arrival,TOA)多阶差分序列估计了雷达PRI调制周期,并基于直方图算法重构了PRI周期样本图;然后,以PRI周期样本图为基础,提出了5个PRI调制特征实现PRI调制类型识别;该方法不仅能够提升PRI调制类型的识别准确率,而且对干扰脉冲特别是脉冲丢失具有很强的稳健性;最后,仿真实验表明了所提方法的有效性。
文摘该文以三相电压型脉宽调制(pulse width modulation,PWM)整流器为研究对象,提出一种基于新型开关表的直接功率控制(direct power control,DPC)策略。首先,根据两相旋转dq坐标系下整流器数学模型计算开关矢量对有功功率和无功功率的控制幅度,并归一化处理进行定量分析,以此为基础将传统DPC的12扇区重新划分为24扇区。然后,设计有功功率差值区间判断器,根据其输出值Cp和有功功率与无功功率滞环比较器的输出值Sp、Sq,选择当前扇区最佳开关矢量构造新型开关表,实现对有功功率的精确控制。仿真对比表明,该新型开关表不仅克服传统开关表对无功功率控制能力差的缺点,而且改善网侧电流总谐波失真,降低输出直流电压波动和有功功率与无功功率脉动。最后,搭建一台800W三相电压型PWM整流器样机,通过对比实验验证所提控制策略的正确性和有效性。
文摘遥传技术是随钻测量(MWD,measurement while drilling)系统中的一项关键技术,目前大多数MWD系统均采用泥浆脉冲方式进行数据传输。随着井深的增加,单纯的脉冲调制的传输性能会快速恶化。提出了一种联合卷积编码与脉冲间隔调制,构造出一种网格编码脉冲间隔调制(TC-PIM)方法。TC-PIM最大化调制输出序列之间的最小时间距离,从而获得显著的编码增益。TC-PIM可以用于随钻测量系统,以提高泥浆脉冲遥传系统的传输距离。
