近年来,全球风力发电装机容量呈指数型增长。然而,现有航管一次雷达的动目标检测(Moving Target Detector, MTD)技术无法抑制具有非零频成分的风电场杂波,可能导致目标遮蔽和虚警率上升。针对此问题,该文提出了一种在风电场杂波下航管一次雷达的目标检测方法。该方法在MTD前端设置风电场杂波抑制器。在该抑制器中首先估计雷达回波每个距离单元的谱中心,并把所有距离单元的谱中心移到零频。其次利用类似于对消固定杂波的方法对消目标回波,而具有较宽频谱宽度的风电场杂波经对消后仍有大部分的能量剩余。然后采用恒虚警率(Constant False Alarm Rate, CFAR)检测确定杂波所在的距离单元,并剔除待检测数据中所有杂波单元,解决了风电场杂波进入非零频多普勒滤波器可能导致当前航管一次雷达MTD检测性能急剧恶化的问题。实验结果表明该方法对风电场杂波强度不敏感,有效地消除了杂波对目标的遮蔽现象并控制了由杂波引起的虚警率上升。%In recent years, the global wind power installed capacity is growing exponentially. However, current Moving Target Detector (MTD) of primary surveillance radar can not suppress the wind farm clutter. The non-zero frequency components of the wind farm clutter may produce target losing and higher false alarm. A novel method for radar target detection in wind farm clutter is proposed. The method sets a wind farm clutter suppressor before current MTD. First, the center Doppler frequency of each range cell is estimated and the spectral center of each range cell is shifted to the zero frequency. Then, target echo is removed with the method similar to canceling stationary clutter. The wind farm clutter with rather wide spectral width still reserves most of energy after canceller process. Finally, the clutter units detected by Constant False Alarm Rate (CFAR) are eliminated. The proposed method prevented the obvious deterioration of current MTD detection due to clutter energy spreading into non-zero Doppler filters. The experimental results indicate that the method conqueres the problem of masked target and decreased false alarms effectively are not sensitive to the power of the wind farm clutter.
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