实时准确正弦波频率估计综合算法

为了对正弦波信号频率进行快速、准确估计,以便同时满足实时性和精度的要求,文中补充Rife算法采用了最大谱线及其两边相邻谱线的一种细化估计,在相同的条件下,改善了Rife算法的信噪比要求,提高了在频率真值接近离散频率值时的估计精度,但在频率真值偏离离散频率值时的估计误差较大;进一步提出的综合算法是在最大谱线检测的基础上,对其两边谱线进行提高一倍分辨的频谱细化,根据两边细化分析的谱线比值T决定采用修正Rife算法进行频率估计(T>1 5)或细化补充Rife算法进行频率估计(T<1 5).文中对多种算法进行了500次统计模拟,结果表明,综合算法不仅具有良好的估计精度,而且具有良好的频域稳定性.

A realtime and accurate sinusoidal frequency estimation synthetic approach

The method was studied to exactly estimate the frequency of the sinusoidal signal as quickly as possible, which would satisfy the requirements for real-time processing and accuracy. The completed Rife algorithm provided by this paper is a fined frequency estimate that also uses another two spectrum pints beside the maximum spectrum point. In the same condition, it has a lower SNR and is more accurate than the Rife algorithm when the truth frequency is near those spectrum points. But it will have a great deviation when the truth frequency is away from those spectrum points. The synthesized algorithm which is also proved by this paper is another frequency estimate based on the detected maximum spectrum point. First, two spectrum points beside the maximum point are fined at half frequency step, and then the T is used which is the ratio of the new fined spectrum points to determine which algorithm will be empolyed. The modified Rife algorithm is employed as the T>1.5 and the fine completed Rife algorithm is employed as the T≤1.5. 500 simulation for various algorithms show that the synthesized algorithm not only has a good estimation accuracy, but also has a good frequency stability.