A Reconfigurable Multi-Modal SDR Transceiver for CubeSats

As the attention towards CubeSats increases due to their low manufacturing and launch costs, it becomes more and more relevant equipping them with Software-Defined-Radio (SDR) technologies to fulfill tasks for various scientific missions. The most recent state-of-the-art about small satellites is quickly moving toward this direction. To provide the highest degree of flexibility, we decided to build a basic baseband multicarrier infrastructure, exploiting the usual Fast-Fourier Transform (FFT) digital signal processing module. In such a way, we provide a software-defined transceiver capable at supporting all standard and non-standard multicarrier transmission waveforms, namely: OFDMA, SC-FDMA and MC-CDMA, but also capable at reconfiguring itself in single-carrier mode with Frequency-Domain Equalization (SC-FDE) and, if needed, even in single-carrier DS/CDMA mode. The dynamic reconfiguration of the receiver is enabled by a waveform recognition block, based on the analysis of the cross-correlation of the received signal in the time/frequency domain. After introducing the motivations and the state-of-the-art framework, the paper describes in detail the software architecture of the transceiver, implemented with open-source GNU Radio tools. Preliminary results will be then presented, aimed at assessing the performance of the proposed SDR-based transceiver. Finally, some considerations will be drawn, concerning with the concrete feasibility of the proposed SDR implementation in the framework of commercial low-cost digital signal processing platforms.