为解决相干跳频和直接序列扩频结合的抗干扰测控信号在大时差大多普勒条件下快速捕获的问题,采用基于FFT并行相关的分段码相关算法,实现积分时长为单个跳频段的快速码相位滑动相关;采用相位补偿算法,补偿各个跳频段间因时间差、跳频频...为解决相干跳频和直接序列扩频结合的抗干扰测控信号在大时差大多普勒条件下快速捕获的问题,采用基于FFT并行相关的分段码相关算法,实现积分时长为单个跳频段的快速码相位滑动相关;采用相位补偿算法,补偿各个跳频段间因时间差、跳频频率和多普勒导致的相位差,实现了较大多普勒频偏条件下跳频段之间的相干累加。与非相干累加相比,本算法消除了大时差大多普勒条件对信号长时间相干累积的影响,在某信号体制下检测性能提升9 d B,代价是算法复杂度随捕获时间分辨率的增加而线性增加10倍。本算法可改变搜索精度,能灵活适应不同应用背景下扩频应答机的计算资源限制,目前已经应用于某卫星系统的测控应答机。展开更多
An signal noise ratio（ SNR） adaptive sorting algorithm using the time-frequency（ TF）sparsity of frequency-hopping（ FH） signal is proposed in this paper. Firstly,the Gabor transformation is used as TF transformat...An signal noise ratio（ SNR） adaptive sorting algorithm using the time-frequency（ TF）sparsity of frequency-hopping（ FH） signal is proposed in this paper. Firstly,the Gabor transformation is used as TF transformation in the system and a sorting model is established under undetermined condition; then the SNR adaptive pivot threshold setting method is used to find the TF single source. The mixed matrix is estimated according to the TF matrix of single source. Lastly,signal sorting is realized through improved subspace projection combined with relative power deviation of source. Theoretical analysis and simulation results showthat this algorithm has good effectiveness and performance.展开更多
文摘为解决相干跳频和直接序列扩频结合的抗干扰测控信号在大时差大多普勒条件下快速捕获的问题,采用基于FFT并行相关的分段码相关算法,实现积分时长为单个跳频段的快速码相位滑动相关;采用相位补偿算法,补偿各个跳频段间因时间差、跳频频率和多普勒导致的相位差,实现了较大多普勒频偏条件下跳频段之间的相干累加。与非相干累加相比,本算法消除了大时差大多普勒条件对信号长时间相干累积的影响,在某信号体制下检测性能提升9 d B,代价是算法复杂度随捕获时间分辨率的增加而线性增加10倍。本算法可改变搜索精度,能灵活适应不同应用背景下扩频应答机的计算资源限制,目前已经应用于某卫星系统的测控应答机。
基金Supported by the National Natural Science Foundation of China(64601500)
文摘An signal noise ratio（ SNR） adaptive sorting algorithm using the time-frequency（ TF）sparsity of frequency-hopping（ FH） signal is proposed in this paper. Firstly,the Gabor transformation is used as TF transformation in the system and a sorting model is established under undetermined condition; then the SNR adaptive pivot threshold setting method is used to find the TF single source. The mixed matrix is estimated according to the TF matrix of single source. Lastly,signal sorting is realized through improved subspace projection combined with relative power deviation of source. Theoretical analysis and simulation results showthat this algorithm has good effectiveness and performance.
