  The burgeoning interest within the space community in digital beamforming is
largely attributable to the superior flexibility that satellites with active
antenna systems offer for a wide range of applications, notably in
communication services. This paper delves into the analysis and practical
implementation of a Digital Beamforming and Digital Down Conversion (DDC)
chain, leveraging a high-speed Analog-to-Digital Converter (ADC) certified for
space applications alongside a high-performance Field-Programmable Gate Array
(FPGA). The proposed design strategy focuses on optimizing resource efficiency
and minimizing power consumption by strategically sequencing the beamformer
processor ahead of the complex down-conversion operation. This innovative
approach entails the application of demodulation and low-pass filtering
exclusively to the aggregated beam channel, culminating in a marked reduction
in the requisite digital signal processing resources relative to traditional,
more resource-intensive digital beamforming and DDC architectures. In the
experimental validation, an evaluation board integrating a high-speed ADC and a
FPGA was utilized. This setup facilitated the empirical validation of the
design's efficacy by applying various RF input signals to the digital
beamforming receiver system. The ADC employed is capable of high-resolution
signal processing, while the FPGA provides the necessary computational
flexibility and speed for real-time digital signal processing tasks. The
findings underscore the potential of this design to significantly enhance the
efficiency and performance of digital beamforming systems in space
applications.
