合成孔径成像激光雷达是一种新的主动式有源成像系统,其突出优势是可以获得比合成孔径雷达更高的分辨率,和更接近光学图片的成像质量。对激光波段的高分辨距离像进行了研究,介绍了合成孔径成像激光雷达一维距离像的室内实验系统,有效地对合成孔径成像激光雷达一维距离像进行模拟。首先,简述了一维距离像的成像原理。然后,分析了系统的关键技术,给出了系统框图和连接关系,并且针对激光调谐信号的非线性问题,利用多项式推导出非线性的激光信号表达式,提出了一种时域补偿高阶相位误差的补偿方法。最后,通过实验证明了所提方法可以有效地消除各个脉冲的非线性问题,并且表明所给实验系统的可行性。
Synthetic aperture imaging lidar is a new active imaging system,which can realize a finer azimuth resolution than that in conventional SAR system,and obtain higher imaging quality whose fidelity is close to the effect of the optical pictures.An indoor -scale experimental system of synthetic aperture imaging lidar was given,which was a demonstration of imaging with high resolution range profile in laser waveband.Firstly,the basic principle of the dechirp -receiving method was depicted.Secondly,on the basis of analysis of key technique,the system block diagram and connection relation were introduced.Since the nominal chirped laser waveforms was not perfectly linear and unstable from pulse to pulse,the expression of the laser signal using a polynomial form was prenested with respect to the tunable time in each pulse,and a compensation algorithm for pulse′s high-order phase error was given which was based on the reference channel and performed in the time domain.Finally,the result of imaging system was provided,which shows the proposed algorithm can efficiently mitigate nonlinearity of each echo and proves the feasibility of the given experimental system.