SwaMURAy - Swapping memory unit for radio astronomy

This paper concerns design and performance testing of an HDL module called SwaMURAy that is a configurable, high-speed data sequencing and flow control module serving as an intermediary between data acquisition (or pre-processing) and subsequent processing stages. While a FIFO suffices for many applications our case needed a more elaborate solution to overcome legacy design limitations. The SwaMURAy is designed around a system where a block of sampled data is acquired at a fast rate and is then distributed among multiple processing cores to achieve a desired processing rate; this pattern of processing is sometimes needed in software defined radio (SDR) and radio astronomy applications. This solution was partly in response to legacy design restrictions of the SDR platform used, a difficulty likely experienced by many developers whereby new sampling peripherals are inhibited by legacy characteristics of the underlying reconfigurable platform. Our SDR platform has a planned lifetime of at least five years; a complete redesign and re-fabrication would be too costly. While the SwaMURAy overcame some performance problems, other problems arose. This paper overviews the SwaMURAy design, performance improvements achieved in a SDR case study, and remaining limitations and workarounds we expect will achieve further improvements.