This paper presents the integration and channel characterization of a highly integrated dual-band digital beamforming space-borne synthetic aperture radar (SAR) receiver. The proposed SAR sensor is a low-cost, lightweight, low-power consumption, and dual-band (X/Ka) dual-polarized module ready for the next-generation space-borne SAR missions. In previous works, by the authors, the design and experimental characterization of each sub-system was already presented and discussed. This work expands upon the previous characterization by providing an exhaustive experimental assessment of the fully integrated system. As it will be shown, the proposed tests were used to validate all the instrument channels in a set-up where the SAR sensor was illuminated by an external source minim the ground reflected waves. Test results demonstrate how the system channels are properly operating allowing the reception of the input signals and their processing in the digital domain. The possibility to easily implement a calibration procedure has also been validated to equalize, in the digital domain, the unavoidable amplitude differences between the different channels.

中文翻译：

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具有数字波束形成的双频带双极化 SAR 的信道表征

本文介绍了高度集成的双频段数字波束成形星载合成孔径雷达 (SAR) 接收机的集成和信道表征。所提出的 SAR 传感器是一种低成本、轻量级、低功耗的双频 (X/Ka) 双极化模块，可用于下一代星载 SAR 任务。在作者之前的作品中，每个子系统的设计和实验特性已经被介绍和讨论过。这项工作通过提供对完全集成系统的详尽实验评估，扩展了先前的表征。正如将要展示的那样，所提出的测试用于验证设置中的所有仪器通道，其中 SAR 传感器由外部光源照射，以最大限度地减少地面反射波。测试结果展示了系统通道如何正常运行，从而允许接收输入信号并在数字域中对其进行处理。轻松实施校准程序的可能性也已经过验证，可以在数字域中均衡不同通道之间不可避免的幅度差异。