This paper provides a direct and fast acquisition algorithm of civilian long length(CL) codes in the L2 civil(L2C) signal. The proposed algorithm simultaneously reduces the number of fast Fourier transformation(...This paper provides a direct and fast acquisition algorithm of civilian long length(CL) codes in the L2 civil(L2C) signal. The proposed algorithm simultaneously reduces the number of fast Fourier transformation(FFT) correlation through hyper code technique and the amount of points in every FFT correlation by using an averaging correlation method. To validate the proposed acquisition performance, the paper applies this algorithm to the real L2C signal collected by the global positioning system(GPS) L2C intermediate frequency(IF) signal sampler—SIS100L2C. The acquisition results show that the proposed modified algorithm can acquire the code phase accurately with less calculation and its acquisition performance is better than the single hyper code method.展开更多
针对电力系统故障录波数据的存储和传输问题,提出了基于CL多小波和多级树集合分裂SPIHT(Set Partitioned in Hierarchical Tree)编码的数据压缩方法。首先对故障录波数据进行CL多小波变换,然后对变换以后的系数进行一维SPIHT编码,对得...针对电力系统故障录波数据的存储和传输问题,提出了基于CL多小波和多级树集合分裂SPIHT(Set Partitioned in Hierarchical Tree)编码的数据压缩方法。首先对故障录波数据进行CL多小波变换,然后对变换以后的系数进行一维SPIHT编码,对得到的排序位流再进行算数编码。实验结果表明该算法在压缩比为8.2907%时,均方误差为0.4544%,信噪比达46.8504,同时该算法可以根据需要自由控制压缩比,实现了可变码率,在应用中可得到满意的压缩效果。展开更多
基金supported by the Fundamental Research Fund for the Central Universities(NS2013016)
文摘This paper provides a direct and fast acquisition algorithm of civilian long length(CL) codes in the L2 civil(L2C) signal. The proposed algorithm simultaneously reduces the number of fast Fourier transformation(FFT) correlation through hyper code technique and the amount of points in every FFT correlation by using an averaging correlation method. To validate the proposed acquisition performance, the paper applies this algorithm to the real L2C signal collected by the global positioning system(GPS) L2C intermediate frequency(IF) signal sampler—SIS100L2C. The acquisition results show that the proposed modified algorithm can acquire the code phase accurately with less calculation and its acquisition performance is better than the single hyper code method.
文摘针对电力系统故障录波数据的存储和传输问题,提出了基于CL多小波和多级树集合分裂SPIHT(Set Partitioned in Hierarchical Tree)编码的数据压缩方法。首先对故障录波数据进行CL多小波变换,然后对变换以后的系数进行一维SPIHT编码,对得到的排序位流再进行算数编码。实验结果表明该算法在压缩比为8.2907%时,均方误差为0.4544%,信噪比达46.8504,同时该算法可以根据需要自由控制压缩比,实现了可变码率,在应用中可得到满意的压缩效果。