浅海水声信道是目前最困难的无线通信信道之一,可建模成稀疏衰落信道,其噪声以S S分布来描述.提出了基于H1自适应滤波的稀疏双选衰落信道估计算法,针对S S分布噪声中个别脉冲对信道估计影响较大的情况,分别对信号的实虚部进行限幅以消除影响算法稳定度和性能较大的脉冲噪声. 仿真结果表明:在S S分布噪声下,所提出的针对脉冲噪声的5预处理提升了系统性能;无论是多径信道还是双选衰落稀疏信道,基于H1自适应滤波的信道估计算法的性能优于sIPNLMS算法.
Shallow sea is a difficult channel for acoustic communications. Noise in shallow sea acoustic communications may be described by the S S distribution, and the channel modeled as a sparse double selective fading channel. The H1 adaptive filtering is specially designed for none-Gaussian noise, and therefore can be used for channel estimation in an S S noise environment. This paper proposes an algorithm to solve the channel estimation problem based on the H1 adaptive filtering. In addition, to solve the performance degradation problem due to serious individual pulse noise, a signal preprocessing method is proposed. The results show that the performance is improved because of the preprocessing. It is shown that the performance of the H1
adaptive filtering is better than sIPNLMS both in a sparse multipath channel and in a sparse double selective channel.
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