基于空间时频分布的高频雷达接收阵校正

Array Calibration Based on the Spatial Time-Frequency Distribution for HFSWR

传统阵列校正大多使用目标的空间相关矩阵,利用信号的时域或频域信息对阵列的幅相误差进行估计。但在实际应用中,由于时域信号信噪比无法满足要求,频域信号快拍数目又过少,导致无法准确估计出目标的空间相关矩阵,从而极大地影响了阵列的校正效果。针对此问题,首次利用空间时频分布理论进行阵列校正,通过时频点的选取提高信噪比,使校正效果和误差容限得到提升。通过计算机仿真给出了该方法与传统方法的性能对比,最后将该方法应用到实测雷达数据中,验证了校正的有效性与可行性。

The traditional array calibration usually uses target＇s spatial correlation matrix（SCM）estimated by time-domain or frequency-domain information of the signal.However,in practice,the signal to noise ratio（SNR）of time-domain signal cannot meet the requirements and the number of frequency-domain snapshots is too small,making it impossible to estimate SCM of the target accurately and thus affecting the calibration results greatly.To solve this problem,the paper firstly applies spatial time-frequency distribution theory to array calibration.SNR is improved through the selection of time-frequency points that both calibration effect and error capacity are improved.And then the performance comparison between the proposed method and the traditional method is given by computer simulation.Finally,the proposed method is applied to the measured radar echo data to verify the effectiveness and feasibility of calibration.