直升机载合成孔径雷达(SAR)是微波成像的潜在重要发展方向。由于直升机平台具有高频振动的特殊性,目标在SAR 图像上会呈现出对称重影,严重影响图像的判读与应用。针对该难题,文中对直升机载SAR 回波信号的额外调制进行理论分析和建模,并结合成像处理流程,提出一种高频相位误差精准补偿方法。实测数据验证结果表明,该方法可实现直升机载SAR 的正常、高质量成像,为直升机载SAR 成像提供了重要技术支撑。

Helicopter-borne synthetic aperture radar (SAR) is an important underlying development aspect of microwave imaging. Because of the particularity that helicopters own high frequency vibrations, targets on the SAR image will take on two symmetrical replicas, which seriously affect the judgment and application of the image. Aim at this difficulty, the extra modulation of the helicopter-borne SAR echoes is investigated theoretically and modeled, and a method that can be used to exactly compensate high frequency phase errors are proposed according to the image formation procedure. Experimental data results demonstrate that the proposed method can normally realize helicopter-borne SAR high quality imaging, providing an important technical support for helicopter-borne SAR image formation.

TN958