基于改进时频脊线的多用户宽带跳频信号参数估计方法

Parameter Estimation Method of Multi-broadband Frequency Hopping Signal Based on Improved Time-frequency Ridge

摘要:

针对多用户宽带跳频信号参数估计问题，提出了一种基于改进时频脊线的参数估计方法；基于短时傅立叶变换获得的时频矩阵，进行最高与最低时频脊线的计算和处理，联合两时频脊线差分结果进行滑窗处理，进而获得了跳频时刻粗估计结果，基于漏跳问题，实现了跳频时刻校正，使用矫正后的结果，通过最小二乘拟合，计算得到了跳速与跳频时刻的估计结果；经仿真试验测试，验证了该算法在不同带宽和跳速下的有效性，跳速估计平均值准确，标准差在0.006%以内，跳频时刻估计误差平均值和标准差分别在0.18%和0.14%以内；经实测跳频信号测试，跳速估计平均值准确，标准差在0.03%以内；算法实现了多用户宽带跳频信号的跳速和跳频时刻估计，且计算量小，具有工程应用前景。

Abstract:

Aiming at the problem of parameter estimation of multi-users broadband frequency hopping signals, a parameter estimation method based on improved time-frequency ridge is proposed. Based on the time-frequency matrix obtained by Short-time-Fourier transform (STFT), the calculation and processing of the highest time-frequency ridge and the lowest time-frequency ridge are carried out, and the sliding window processing is carried out by combining the difference results of the two time-frequency ridges, and then the rough estimation results of the frequency hopping time are obtained. Based on the problem of missing hops, the frequency hopping time correction is realized. Using the corrected results, the estimation results of the hopping speed and the frequency hopping time are calculated by the least square fitting. The effectiveness of the algorithm under different bandwidth and hopping speed is verified by simulation test. The average of the hopping speed estimation results is accurate, and the standard deviation is within 0.006%. The average values of the estimation error and the standard deviation of hopping time is 0.18% and 0.14% respectively. Through the test of measured frequency hopping signal, the average of the hopping speed estimation results is accurate, and the standard deviation is within 0.03%. The algorithm realizes the estimation of hopping speed and hopping time of multi-broadband frequency hopping signals, and the calculation amount is small, which has the prospect of engineering application.