摘要
针对垂直水声通信中时变多普勒引起的定时偏差问题,研究一种基于伪随机序列的迭代定时估计及补偿算法。该方法利用伪随机序列作为同步信号,分三步估计时变多普勒:采用低复杂度的模糊函数法粗补偿接收信号内的平均多普勒;通过迭代插值法实现残留时变多普勒的精确估计及补偿;利用基于信道相关函数的相位信息,纠正均衡后信号的偏转相位。为实现高阶海试数据的有效解调,采用基于伪随机序列均方误差的多通道加权合并方式,获得空间分集增益。仿真及海试数据处理结果证明所提方法具有良好的时变多普勒估计及补偿性能,同时对30个通道内的1024QAM数据进行合并处理,在500 m的通信距离下,误码率为0.04,信道容量达到7.6 bits/symbol。与传统数据帧结构相比,无需使用线性调频信号,可以提高有效数据传输率。
To solve the problem of timing error caused by time-varying Doppler in vertical underwater acoustic communication,an iterative timing estimation and compensation algorithm based on pseudo-random sequence is studied in this paper.The method uses pseudorandom sequence as synchronization signal,and estimates time-varying Doppler in three steps:a low complexity ambiguity function is used to roughly compensate the average Doppler in the received signal;the accurate estimation and compensation of residual time-varying Doppler are realized by iterative interpolation method;the phase information of correlation function based on the channel is used to correct the deflection phase of the equalized signal.Then,to further realize the effective demodulation of high-order sea trial data,multi-channel weighted combination based on mean square error of pseudo-random sequence is adopted to obtain spatial diversity gain.The simulation and sea trial data processing results show that the proposed method has good time-varying Doppler estimation and compensation performance,and the 1024QAM data in 30 channels are combined and processed.At the communication distance of 500 m,the BER is 0.04,and the channel capacity reaches up to 7.6 bits/symbol.Compared with the traditional data frame structure,the linear frequency modulation signal is unnecessary,so the effective data transmission rate can be improved.
作者
王达
朱敏
武岩波
褚润聪
WANG Da;ZHU Min;WU Yanbo;CHU Runcong(Ocean Acoustic Technology Laboratory,Institute of Acoustics,Chinese Academy of Sciences,Beijing 100190,China;University of Chinese Academy of Sciences,Beijing 100049,China;Beijing Engineering Technology Research Center of Ocean Acoustic Equipment,Beijing 100190,China;State Key Laboratory of Acoustics,Institute of Acoustics,Chinese Academy of Sciences,Beijing 100190,China)
出处
《应用声学》
CSCD
北大核心
2024年第2期262-274,共13页
Journal of Applied Acoustics
基金
中国科学院战略性先导科技专项(A类(XDA22030101))
国家自然科学基金项目(61971472)
国家重点研发计划项目(2021YFC2800200)。
关键词
水声通信
伪随机序列
多普勒估计
多通道合并
Underwater acoustic communication
Pseudo random sequence
Doppler estimation
Multi channel merge
