基于频域平滑循环周期图法的直接序列扩频信号的参数估计  

Parameter estimation of the direct sequence spread spectrum signal based on frequency-smoothing symmetrical periodogram

作　　者：汪赵华[1,2] 陈昊[2] 郭立[1] 

机构地区：[1]中国科学技术大学电子科学与技术系,安徽合肥230027 [2]解放军电子工程学院,安徽合肥230037

出　　处：《中国科学技术大学学报》2010年第5期466-473,共8页JUSTC

基　　金：国家自然科学基金(60175018);安徽省自然科学基金(050420101)资助

摘　　要：根据直接序列扩频(DS-SS)信号的传输特点,将其建立为循环平稳模型.利用基于频域平滑的周期图估计了DS-SS信号的码元速率、载波频率、初始时间和初始相位,提高了参数估计精度.在循环谱密度函数的数字实现过程中,用频域平滑后的循环周期图估计循环谱密度函数,推导了在有限数据条件下循环谱的对称式周期图估计和频域平滑对称式周期图估计的方差表达式,分析了经过频域平滑后的DS-SS信号参数估计方差和估计精度.最后,仿真实验验证了算法的有效性.An algorithm for estimating the code rate, carrier frequency, initial time and phase ot the direct sequence spread spectrum （DS-SS） signals was proposed using frequency-smoothing symmetrical periodogram instead of cyclic spectrum according to cyclostationary feature of DS-SS signal to improve the precision of parameter estimation. The variance expression of estimation for the cyclic spectrum was deduced by the symmetrical periodogram and frequency smoothing symmetrical periodogram. The estimation performance was analyzed for the cyclic spectrum by frequency-smoothing symmetrical periodogram from variance and precision of parameter estimation in the ease of limited length. Simulation results show that the proposed algorithm is effective.

关 键 词：直接序列扩频(DS-SS)信号 循环谱 参数估计 

分 类 号：TN911[电子电信—通信与信息系统] TN929[电子电信—信息与通信工程]