Central Signal Processor


Design of the SKA Central Signal Processing (CSP) Element

Who are we?

The “Central Signal Processor” (CSP) Consortium is comprised of 13 signatories from 8 countries with more than 10 additional participating organizations. The Consortium includes a rich mixture of engineers, scientists and managers from various academic institutions, industry and government labs spread over 5 continents (see https://www.skatelescope.org/csp/ for more details). As might be expected, it has been a challenge to proceed efficiently with such a diverse and distributed team.

The lead organisation of the Consortium is the National Research Council of Canada (NRC). NRC has contracted MDA Systems Ltd. (a Maxar Company) to assist in leading the Consortium.

What are we designing?

The CSP Element includes design of the hardware and associated firmware/software necessary for the generation of visibilities, searching for new pulsar candidates, and producing high-fidelity pulsar timing data from the telescope arrays. More background on the CSP can be found in the previous eNews submissions: https://newsletter.skatelescope.org/category/newsletter-archive/

Current Status of Design Activities

Since the last eNews submission in July the CSP Team has completed preparing for and executing the LMC Critical Design Review (CDR) and CSP CDR meetings at SKAO Sept 24-28. Sonja Vrcic led the LMC team through a very successful CDR that preceded the element level review. Many excellent observations were made by the expert review panel members for both CDRs. The Consortium addressed these comments and held constructive discussions at the reviews. Following the reviews, the team made the necessary updates to the documentation package and submitted them by Oct 31 for final SKAO approval. Once final approval has been achieved, the CSP Consortium will cease to exist and the member organizations will continue to support the SKA through the bridging phase via direct MOUs with the SKAO.

The following are some comments by various Consortium leaders, SKAO and CDR review panel members:

Luc Simard, CSP Consortium Leader, NRC: “It’s been a wonderful experience, wonderful bunch of people, extremely talented, extremely knowledgeable. We have the best of the best, and working with them has been a real honor. I’d like to thank them from the bottom of my heart.”

David Stevens, CSP Consortium Project Manager, MDA Systems Ltd.: “This has been a fascinating journey for me starting over 6 years ago when Brent Carlson and I visited all the potential CSP partners to form the CSP Consortium. Over the pre-construction period we have had our fill of challenges as we went through re-baselining activities and the down-selection process and the resulting reconfigurations of the Consortium. Throughout the team has been committed to delivering the best telescope possible and produced a truly outstanding design for the CSP that is compliant to requirements, cost effective, and power efficient. I am very grateful for being able to work with such a terrific team and have learned a great deal from everyone. I would like particularly to thank Philip Gibbs and Wallace Turner of the SKAO (and the rest of the IET) for working so cooperatively with us all these years. I look forward to continuing to work with you all going forward.”

CSP Element CDR Review Panel: “The Element design is convincing, providing detailed analysis and rationale for the partitioning of the Element, for both Mid and Low telescopes, into the Sub-Elements with thorough traceable flow down of requirements and interfaces. Where assumptions have been made these have been clearly and formally captured and reviewed (these will provide an invaluable resource in progressing the SKA1 Project towards its System CDR). The development, prototyping, integration and testing of a viable implementation of the CSP Element are clearly identified with a consistent level of design detail across all documentation. The designs are convincing, with supporting simulation and modelling results indicating that nearly all functional requirements will be met.

An impressive volume of documentation was delivered in plenty of time for the review. This documentation was consistently comprehensive, clear and well written describing the design in an appropriate level of detail showing that the performance has been rigorously checked against the requirements though there are a few non-compliant and partially compliant items which are documented. The Panel believes, given the provided rationales, these have negligible impact on the telescopes.

The Consortium have produced simple but efficient architectures optimised to work within the extremely tight constraints of low power consumption and cost whilst minimising risk. The Frequency-slice concept and the Pulsar Search’s processing density are major contributors in this regard. Innovations such as the frequency offset scheme for the Mid telescope offers improved performance for the Telescope regarding RFI suppression and reduction of aliasing artefacts.

It has been difficult for the Panel to identify any gaps specific to CSP due to the high quality and completeness of the CSP CDR submission.

The Review Panel unanimously and unreservedly recommend that the CSP Element team have fully passed the Element CDR review.”

Title “CSP Element CDR Meeting at SKAO Sept 24-28, 2018. This only represents a small fraction of the full team. Of particular note missing: Willem van Straten and Peter Baillie of AUT and Nicolas Loubser of MDA.”

Report provided by the CSP consortium