LuTan-1 (LT-1) refers to an innovative mission of spaceborne bistatic synthetic aperture radar (BiSAR) adopting the phase synchronization scheme of pulse exchange, which is scheduled to be launched in 2020. In this mission, the multipath effect caused by the reflection of satellites and Doppler frequency shift resulting from the relative motion between satellites constitute two critically latent factors deteriorating the performance of the phase synchronization scheme. This article details a loss factor to evaluate the fading of synchronization signals under the reflection of smooth and rough surfaces and estimates the influence of Doppler frequency shift on synchronization signals. Furthermore, the multipath channel impulse response is modeled, and the correlation characteristics of multipath channel are described by the coherent bandwidth and coherent time. In addition, two simulation experiments based on the system parameters of LT-1, are implemented to assess the influence of time-invariant and -varying multipath effects on the phase synchronization scheme. A scale experiment is also executed to quantify the influence of multipath effect on phase synchronization, and its result demonstrates that the phase synchronization scheme of LT-1 can not only achieve full coverage of space and backup capability of pulse exchange but also meet the application requirements under multipath effect.

中文翻译：

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LT-1 相位同步方案中多径效应的首次演示

LuTan-1（LT-1）是指采用脉冲交换相位同步方案的星载双基地合成孔径雷达（BiSAR）创新任务，计划于2020年发射。卫星的反射和由卫星之间的相对运动引起的多普勒频移构成了两个严重的潜在因素，使相位同步方案的性能恶化。本文详细介绍了在光滑和粗糙表面反射下评估同步信号衰落的损耗因子，并估计多普勒频移对同步信号的影响。此外，多径信道脉冲响应被建模，多径信道的相关特性用相干带宽和相干时间来描述。此外，还基于 LT-1 的系统参数进行了两个仿真实验，以评估时不变和变化的多径效应对相位同步方案的影响。还进行了规模化实验，量化了多径效应对相位同步的影响，结果表明LT-1的相位同步方案不仅可以实现空间全覆盖和脉冲交换备份能力，还可以满足应用需求。在多径效应下。实施以评估时不变和变化的多径效应对相位同步方案的影响。还进行了规模化实验，量化了多径效应对相位同步的影响，结果表明LT-1的相位同步方案不仅可以实现空间全覆盖和脉冲交换备份能力，还可以满足应用需求。在多径效应下。实施以评估时不变和变化的多径效应对相位同步方案的影响。还进行了规模化实验，量化了多径效应对相位同步的影响，结果表明LT-1的相位同步方案不仅可以实现空间全覆盖和脉冲交换备份能力，还可以满足应用需求。在多径效应下。