This paper presents the feasibility of performing multiple spacecraft per aperture (MSPA) ground operations by using a low-cost software-defined baseband (SDB). The SDB is a Consultative Committee for Space Data Systems (CCSDS)-compliant baseband that employs a personal computer for signal processing and a low-cost commercial-off-the-shelf RF front end for RF signal sampling. The SDB is customized to offer traditional telemetry, tracking, and command (TT&C) services for near-Earth missions operating in S band. The study starts by reviewing MSPA methods already studied by space agencies such as NASA and ESA before going to MSPA methods proposed in the latest CCSDS blue book on RF and modulation systems. The feasibility of operating the CCSDS-proposed multiple uplink carrier MSPA method using the SDB is assessed after evaluating in-band interference and out-of-band emissions from the uplink signals radiated by the low-cost RF front end employed by the SDB. Furthermore, we present a case study where the SDB is used in MSPA operations on a typical solid-state amplifier (SSPA) amplifier typically used in near-Earth missions.

中文翻译：

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将软件定义的基带用于每孔径多空间 (MSPA) 地面操作的可行性

本文介绍了通过使用低成本软件定义基带 (SDB) 执行多个航天器每孔径 (MSPA) 地面操作的可行性。SDB 是一个符合空间数据系统 (CCSDS) 标准的基带咨询委员会，它使用个人计算机进行信号处理，并使用低成本的商用现成射频前端进行射频信号采样。SDB 经过定制，可为在 S 波段运行的近地任务提供传统的遥测、跟踪和指挥 (TT&C) 服务。该研究首先回顾了 NASA 和 ESA 等航天机构已经研究过的 MSPA 方法，然后再研究最新的 CCSDS 射频和调制系统蓝皮书中提出的 MSPA 方法。在评估了 SDB 采用的低成本射频前端辐射的上行链路信号的带内干扰和带外发射后，评估了使用 SDB 运行 CCSDS 提出的多上行链路载波 MSPA 方法的可行性。此外，我们还提供了一个案例研究，其中 SDB 用于 MSPA 操作中的典型固态放大器 (SSPA) 放大器通常用于近地任务。