在分析 Quinn算法性能的基础上, 提出一种改进的 Quinn测频算法, 并对该算法的原理和 FPGA实现步骤进行详细说明。仿真结果表明: 在低信噪比条件下新算法的估计性能不随被估计信号的频率分布而产生波动, 在整个频段内估计均方根误差(RMSE)接近克拉美-罗下界 (CRLB)。为了减少测频时间, 新算法在 FPGA平台实现时采用初始频偏的多项式函数构造频率估计值。实测结果表明新方法测频精确度高, 测频时间短, 可以用于快速测频场合。

An improved Quinn algorithm is proposed based on analyzing the performance of Quinn algorithm. The principle and Field Programmable Gate Array(FPGA) implementation steps of the new algorithm are described in detail. The simulation results indicate that the performance of improved Quinn algorithm does not fluctuate with the distribution of signal frequency, and its Root Mean Square Error(RMSE) approaches to Cramer-Rao Lower Bound(CRLB) throughout the whole frequency range. In order to decrease the latency of frequency measurement, polynomial function of frequency deviation estimator is utilized to implement improved algorithm on FPGA. The experiment results demonstrate the new algorithm with high accuracy and less latency is suitable for fast frequency measurement.