摘要
根据Rife算法在被估计频率接近量化频率时的估计精度较差,但接近两相邻量化频率中心区域时估计精度接近克拉美一罗限的特点,本文提出改进Rife(I-Rife)算法。I-Rife算法利用频移技术和频谱细化技术使信号频率总是位于两相邻量化频率中心区域后,然后再利用Rife算法便可以获得较高的频率估计精度。I-Rife算法改进了判据,降低了频率修正方向的误判概率,使I-Rife算法在低信噪比下仍能保持较高的频率估计精度。仿真结果表明,在信噪比达到-13dB时,I-Rife算法仍保持较高的频率估计精度,而且整个频段上性能稳定。I-Rife算法计算量小,易于硬件实现,可以实时精确的进行正弦波频率估计。
Because the frequency estimate precision of Rife algorithm has a great deviation when the signal real frequency is near to the discrete frequency,but the frequency estimate precision can reach Cramer-Rao lower bound when the signal frequency is near to the midpoint of two neighboring discrete frequencies.An improved Rife（I-Rife） algorithm is presented by moving the signal frequency to the midpoint area of two neighboring discrete frequencies and then the frequency is estimated by Rife algorithm.The ill-judged probability of correctional frequency direction can decrease sharply after using improved criterion.The I-Rife algorithm holds on higher precision even when the SNR reaches to -13dB,but it need lower workload owing to using spectrum subdivision technique.The simulation results indicate that I-Rife algorithm not only has good frequency estimation precision,but also has a good stability in all frequency domains. Frequency estimation of sinusoid wave based on the I-Rife algorithm can be achieved in real-time.It can be implemented easily by the hardware.
出处
《信号处理》
CSCD
北大核心
2010年第10期1573-1576,共4页
Journal of Signal Processing
基金
十一五武器装备预研基金(9140A07020806DZ01)
关键词
频率估计
频谱细化
频谱搬移
克拉美—罗限
frequency estimation
spectrum subdivision
spectrum shift
Cramer-Rao lower bound
作者简介
王宏伟（1972-）男，陕西风翔。西安电子科技大学博士，讲师／工程师，研究方向为信号处理、电子信息对抗。E—mail：xdwanghongwei@163．com
赵国庆（1953-）男，教授，西安电子科技大学博导，从事电子对抗、信号处理等方面的研究。
