SKA Mid Frequency Aperture Array Test Systems

The Mid-Frequency Aperture Array, MFAA, has long been the goal of the SKA - to fulfil the very top-level specification of the instrument: to survey all the neutral hydrogen in the observable universe. This requires instrument(s) which are: very sensitive, provide a fast survey speed and operate from ~50MHz to the rest HI emission at 1421MHz.
Clear candidates to perform this role are Aperture Arrays that provide an all-electronic solution to the collector technology and, in principle, are flexible enough to deliver an optimized solution that can minimize post-processing resources.

The SKA has made the decision to deploy a Low Frequency Aperture Array, LFAA, in SKA phase 1 capable of covering from 50MHz up to 600MHz. Development work is in a consortium led by ASTRON in The Netherlands, but engineering leadership and the crucial antenna technology development is at Cambridge University.

The MFAA development work started in the SKA Design Studies programme (SKADS) in 2005. It should be noted that the Project Engineer for SKADS is based at Cambridge University. SKADS showed that a mid-frequency aperture array is entirely feasible, but requires substantial processing resources - which at the time of completion of SKADS in 2010 were too expensive for the SKA in terms of money and power. The great benefit of a processing based collector system is that industry is developing processing hardware that has increasing performance with reducing power over time.

At this phase of the SKA development it was decided that the MFAA developments should continue as an "Advanced instrumentation Package", AIP, to prepare MFAA for deployment in the mid-2020s as part of the full SKA. There is therefore an MFAA consortium, which has the same leadership as LFAA. A significant benefit of the MFAA development following a few years behind LFAA is that the technologies and concepts developed under the major deployment programme for LFAA are available for use by MFAA. This mitigates cost and risk of MFAA development. LFAA has an on-going and successful sequence of "verification systems" that serve to prove technology development and give confidence in the system capability for the wider SKA community. The larger scale systems are also capable of useful scientific observations, which are beneficial and add to the credibility of the implementations.

This proposal is for the costs of building a mid-frequency aperture array verification system MF-AAVS1 using a sparse antenna based on the chosen design for the SKA Low Frequency aperture array. This enables re-use of many of the concepts and importantly the signal processing developments from the lower frequency system.
MF-AAVS1 build schedule is for 2016 with sufficient time for significant results for the MFAA Preliminary Design review in November 2016.

he SKA is a major new global astronomy facility. It will be operated as an observatory with time awarded via competitive application for observing time. At the same time, the SKA project is a major technical challenge especially within the area of High-performance computing, "Big Data" technologies and energy efficient computing.

The output of the work to be supported by the application will be detailed design and prototyping work for the SKA through to Critical Design review. The delivery of the SKA itself which will follow from this design work will benefit the full academic astronomy community within the partner countries and more widely. In addition the key science goals for the instrument are at the core of modern cosmology and physics and the results will have significant impact beyond the astronomical community both within scientific community more widely but also to Society via our better understanding of the Universe and fundamental physics. We note in particular that SKA phase 1 will provide un-paralled views of the Epoch of deionisation when the first objects form and studies of pulsars within our Galaxy will enable theories of gravity to be tested in extreme conditions and detection of the expected stochastic background of gravitational waves. The UK leadership in key design areas will ensure the UK astronomical community is ideally placed to maximise return from the SKA when operational.

The design work will also have a much wider impact. The SKA is widely recognised as the next BigData challenge within science. As such the required design is pushing the boundaries of those technologies needed to process, analyse and store streaming data. These technologies are critical to the SKA, but are also of wide and general applicability across a broad range of market sectors from standard Data Centres to the analysis and management of data from sensor networks such as those associated with Smart Cities. Via collaboration with major industry partners in the ICT sector and the targeted contracts to be managed as part of this work, the design work to be undertaken will have much wider applicability across the IT market sector. In particular the SKA acts as a single point of focus for many companies both in terms of their own development work, but also as a project for wider collaboration within the sector. In these ways the ICT sector will be a direct beneficiary of the SKA design work. Areas where IP is likely to be developed as part of the design work include new software for file and object stress, new software management layers for Data Centres/HPC facilities especially for BigData challenges, new tools for data management, new analytical approaches for BigData. For these beneficiaries we foresee that the impact may occur in a a number of ways:
1. IP will be developed via this work either jointly or within the industry partners. The IP arrangements in place enable industry partners to exploit this IP while retaining necessary rites for the delivery of the SKA. If the IP is jointly developed appropriate sharing of the results of the impact will be put in place following standard procedures established via Cambridge Enterprise.
2. The SKA design work will provide a focus for some industry partners to develop modified or new products and services which will have wider impact.
3. Direct funding of design work will be undertaken as part of this work. Exploitation of IP derived in this way will be determined by the contractual arrangements with those companies winning competitive tenders while ensuring the delivery of the SKA design according to the SKA IP policy.

Further IP generated wholly within Cambridge will be exploited appropriately via interaction with the University's wholly owned Cambridge Enterprise subsidiary.