浅地层步进变频探地雷达合成孔径算法研究

Research of synthetic aperture algorithms for surface-penetrating stepped frequency radar

合成孔径成像是一种常用的改善方位分辨率的方法。连续波步进变频雷达平均发射功率较高而且可以实现较大的相对带宽,所以在探地应用中可以获得较高的分辨率和较深的探测深度。针对浅地层步进变频探地雷达回波信噪比很低的特点,利用时域回波图像所呈现的双曲线,提出了一种曲线适配的合成孔径成像算法。通过对实测数据处理,证明所提算法在步进变频探地雷达中比传统的合成孔径算法能得到更好的方位分辨率,而且明显增强了目标图像的信噪比。

Synthetic aperture imaging is usually used to improve azimuth resolution. Because continuous wave stepped frequency radar has higher average power and relative bandwidth, it has been comprehensively applied with better azimuth resolution and penetration depth in ground penetrating radar. In view of the basis of lower signal/noise ratio for stepped frequency surface-penetrating radar, a new synthetic aperture algorithm of based-curve matching is given. This algorithm makes use of hyperbolic image of time-domain. The practical simulation results show that this new synthetic aperture algorithm has better azimuth resolution than traditional synthetic aperture algorithms and it enhances the signal/noise ratio of object image.\;