对频率捷变信号成像效果影响因素分析

Analysis of the Factors Influencing on Imaging Effect of the Frequency Agile Signal

针对频率捷变信号成像效果较差的问题,分析了目标运动速度、频率捷变间隔等因素对成像效果的影响。理论分析和仿真结果表明,目标运动所产生的运动速度对成像存在影响,但通过合理的速度补偿,在满足速度补偿精度要求情况下能够提高成像质量。频率捷变信号存在的频点缺失问题是成像效果变差的主要原因。频点缺失会导致合成带宽变小、捷变间隔发生变化,合成后的一维像受栅瓣影响严重,致使成像质量下降。

Aiming at the problem of poor imaging with frequency agile signal,the influence of factors such as target speed and frequency agility interval on the imaging effect is analyzed.Theoretical analysis and simulation results show that the motion speed generated by the target motion has an effect on the imaging,but through reasonable speed compensation,the imaging quality can be improved when the speed compensation accuracy requirements are met.The frequency missing problem of frequency agile signals is the main reason for the poor imaging effect.The lack of frequency will cause the synthesis bandwidth to become smaller and the agile interval to change.The synthesized one-dimensional image is seriously affected by the grating lobes,resulting in a decline in imaging quality.