The echo separation issue associated with different transmit antennas is the most technical challenge in realizing the Multiple-Input Multiple-Output (MIMO) Synthetic Aperture Radar (SAR) system. In this paper, a reconfigurable MIMO-SAR transmission scheme based on inter-pulse and intra-pulse joint phase modulation is proposed. The proposed scheme has many advantages. First, lots of monostatic waveforms can be directly employed in a MIMO-SAR system, which offers flexibility in waveform selection. Second, according to different MIMO-SAR applications, it is reconfigurable and can flexibly adjust the system Degree of Freedoms (DoFs) to accomplish echo separation, achieving the best system performance, which is the key for the multimodal operation of MIMO-SARs. Finally, due to the limited system resources in the real MIMO-SAR system, it is hard to separate echo in a single domain, and the proposed scheme jointly capitalizes DoFs of Doppler, time, and space domains to ensure the successful echo separation. In addition, detailed simulation experiments are carried out to verify the practicability and effectiveness of the newly proposed transceiver schemes.

中文翻译：

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基于脉冲间和脉冲内联合相位调制的可重构MIMO-SAR传输方案


与不同发射天线相关的回波分离问题是实现多输入多输出（MIMO）合成孔径雷达（SAR）系统的最大技术挑战。本文提出了一种基于脉冲间和脉冲内联合相位调制的可重构MIMO-SAR传输方案。所提出的方案有很多优点。首先，大量单基地波形可以直接用于MIMO-SAR系统，这为波形选择提供了灵活性。其次，根据不同的MIMO-SAR应用，它是可重构的，可以灵活调整系统自由度（DoF）来完成回波分离，实现最佳的系统性能，这是MIMO-SAR多模运行的关键。最后，由于实际MIMO-SAR系统中的系统资源有限，很难在单个域中分离回波，所提出的方案联合利用多普勒、时间和空间域的DoF来确保回波分离的成功。此外，还进行了详细的仿真实验，以验证新提出的收发器方案的实用性和有效性。