双基地合成孔径声呐时间同步误差分析

Analysis of time synchronization errors in bistatic synthetic aperture sonar

双基地合成孔径声呐克服了单基地声呐系统的诸多缺陷,在成像等方面有很大优势,但时间同步仍然是一个目前制约成像质量的重要因素,时间同步误差影响是值得关注的重要问题。在回波信号模型和时间同步误差模型基础上,针对双基地合成孔径声呐进行误差影响的理论分析,并进行仿真验证。结果表明,固定时间误差主要引起距离向聚焦位置偏移,线性时间误差引起方位向聚焦模糊和分辨率降低,随机时间误差引起距离与方位向旁瓣升高。

The bistatic synthetic aperture sonar overcomes many shortcomings of the monostatic sonar system,and has great advantages in imaging performance.However,time synchronization technology is still a significant factor that restricts imaging quality,so analysis of time synchronization error is an important issue worthy of attention.Based on the signal echo model and time synchronization error model,the resolution under the influence of error is calculated,and the theoretical analysis of the error influence of the bistatic synthetic aperture sonar is carried out and verified by simulation.The results show that the fixed time error mainly results in focus position migration in distance dimension,the linear time error results in the azimuth focus blur,and the random time error results in the rising of side lobes both in distance dimension and azimuth dimension.