摘要
针对扩频通信网络跳频信号时差估计结果误差过高,导致信号定位追踪能力下降,多领域内信号传播停滞的问题,为增强扩频通信网络跳频信号的传播效率,提高辐射源跟踪和定位系统的信号探测能力,提出基于分数阶傅立叶变换(FRFT:Fractional Fourier Transform)与盲分离的扩频通信网络跳频信号时差估计算法的方法。采用盲分离方法获取满足跳频信号时差估计条件的两条信道,即平坦衰落信道和频率选择性衰落信道,利用FRFT估计两条信道特征,分别将平坦衰落信道特征和频率选择性衰落信道特征与最大似然块检测算法结合,实现扩频通信网络跳频信号的时差估计。实验结果表明,该方法无论是在正常环境中,还是在噪声干扰环境中,其均方根误差均处于较低水平、估计成功率均处于较高水平。
The estimation error of the time difference of the frequency hopping signal in the spread spectrum communication network is too high,leading to a decrease in signal positioning and tracking ability,and signal propagation stagnation in multiple fields.In order to enhance the propagation efficiency of the frequency hopping signal in the spread spectrum communication network and improve the signal detection ability of the radiation source tracking and positioning system.A method for estimating the time difference of hopping signals in spread spectrum communication networks is proposed based on FRFT(Fractional Fourier Transform)and blind separation.The blind separation method is used to obtain two channels that meet the time difference estimation conditions of frequency hopping signals,namely flat fading channel and frequency selective fading channel.The two channel characteristics are estimated by FRFT.The time difference estimation of frequency hopping signals in spread spectrum communication networks is realized by combining the characteristics of flat fading channel and frequency selective fading channel with the maximum likelihood block detection algorithm.The experimental results show that the root mean square error of the proposed method is at a low level and the estimation success rate is at a high level whether in normal environment or noise interference environment.
作者
马煜
MA Yu(Information Construction Management Service,Shaanxi University of Chinese Medicine,Xianyang 712046,China)
出处
《吉林大学学报（信息科学版）》
CAS
2023年第3期396-402,共7页
Journal of Jilin University（Information Science Edition）
基金
国家自然科学基金资助项目(62605012)。
关键词
盲分离
平坦衰落信道
频率选择性衰落信道
分数阶傅立叶变换
时差估计
blind separation
flat fading channel
frequency selective fading channel
fractional fourier transform(FRFT)
time difference estimation
