雷达脉冲信号相位差变化率测量精度的改进算法

Improved Algorithm for Phase Difference Change Rate of Radar Pulse Signals

对于单站无源定位而言,增加相位差变化率这一观测量,可以有效地提高定位速度和精度。给出了一种雷达脉冲信号相位差变化率估计的改进算法,选择准最佳频率估计算法,减小频率估计误差,使脉内积累后信号的信噪比提高N(脉内采样点数)倍;采用解相对无模糊相位差算法,避免了由于差分运算造成的信噪比下降问题。仿真结果表明,在相同信噪比下该算法比现有算法估计精度提高了将近一倍,逼近Cramer-Rao下限,且在较低的信噪比下仍然有很高的估计精度。

Passive location with the information of the phase difference rate of change has many advantages, such as high precision, quick location and so on. An improved algorithm for phase difference change rate of radar pulse signals is proposed. A suboptimal frequency estimation method is used to estimate the frequency and the error of the frequency estimation is reduced. And the signal-to-noise ratio （SNR） is enhanced N times than that of the input SNR （ N is the number of the signal sample within a pulse）. The phase difference change rate is estimated by relative unambiguous phase difference. It can avoid the descending of SNR because of difference operation. The simulation results show that with this improved method the estimated precesion increases approximately one time under the conditions of the same SNR and approaches the Cra- mer-Rao lower bound. And the phase difference rate can estimate accurately under the lower SNR condition.