高斯噪声下差分跳频信号的高分辨率频率检测

差分跳频(DFH)是一种新的高速短波通信体制,它利用相邻跳变频率的变化而不是载频本身来携带信息。跳变频率检测是实现DFH的关键技术之一。本文利用四阶累积量研究了(色)高斯噪声下基于ARMA建模法的DFH信号频率检测,并针对由于模型阶数估计过高而产生的虚检频率,提出一种充分利用信号先验信息的改进算法。仿真结果证明了该方法的有效性,尤其是在低信噪比时仍然能够实现精确检测。

High Resolution Frequency Estimation of Differential Frequency Hopping Signal in Gaussian Noise

Differential Frequency Hopping (DFH) is a new kind of high-speed HF communication system, in which the change of two adjacent frequencies instead of carrier frequency itself, bears the information of symbols. Frequency estimation is one of the key techniques in a DFH communication system. This paper focuses on the research of the frequency estimation of DFH signal in (colored) Gaussian noise by using ARMA-based method with fourth-order cumulants. An improved method, making the most use of the information of the signal itself, is proposed to get rid of the false frequencies caused by the larger order of the estimated ARMA model. Simulation results show that the proposed method is effective,especially in the circumstance of low Signal-to-Noise-Ratio (SNR).