SKATDP Description

The TDP focuses on areas of risk that pertain to performance and cost and that will contribute to key decisions about deploying the SKA. TDP outcomes will contribute significantly to the engineering design phase for the SKA that will commence in the next decade. The two main areas of of risk are:

  1. identifying cost effective ways for producing antenna elements that operate with adequate A/Tsys;
  2. assessing signal processing methods whose costs depend on the number of antennas and thus influence the choice of antenna diameter when the total collecting area is held fixed.

The first of these corresponds to the primary development area in our work breakdown structure (WBS), Antennas, Feeds and Receivers, in which we will develop the technology needed for optimizing the sensitivity of a single antenna while also identifying, through collaboration with manufacturers, how to build antennas at the lowest possible cost. The second area, Calibration and Processing, considers the array aspects of the SKA, including signal transport and processing needed to achieve scientific goals. SKA science comprises a great deal of survey work, whose specifications impact the systems design and cost. Part of our work necessarily considers the role of the SKA as a radio synoptic survey telescope, optimized for discovery and follow-up, and identifying ways in which we can trade field of view against sensitivity.

Activities within the TDP are chosen to tap areas of expertise in the U.S. and which complement work done outside the U.S. Some of our results will comprise unique contributions to the SKA project, while others will be achieved via collaborations within the context of international working groups. For example, while technology development outside the U.S. focuses exclusively on a mid-range frequency band (e.g. 0.3 to 3 GHz), within the U.S. we are also interested in developing technology solutions for the higher frequencies, extended up to perhaps 11 GHz for the mid-range SKA and up to 25 GHz for the full SKA. The deployment plan for the SKA is likely to include in its earliest phases the mid-range band and a low-frequency ``Epoch of Reionization'' (EoR) band (0.1 to 0.3 GHz); for the latter, considerable pathfinder work is being done worldwide (e.g. LOFAR, LWA, MWA). However, the SKA project is not yet informed as to the most cost effective way to define the upper frequency of the mid-range band (given above as 3 GHz only as an example). We need to invest in development of antennas, feeds and receivers and their use in a large-N array as a basis for formulating a sensible, long-term deployment plan for the SKA. This plan must optimize resource development, such as infrastructure and predictable technology trends (e.g. Moore's law), for the entire frequency range demanded by SKA science. Consequently, some of our activity concerns technology solutions for the high-frequency band that will influence early decisions to be made about the overall SKA program.

We must assess the intricate set of tradeoffs that exist between deploying, operating and maintaining a large number of antennas and processing signals to achieve science goals. The multidimensional tradeoff space is the subject of our third work area, costing; it will be coordinated explicitly with the activities of the SPDO to enable decisions needed internationally that will lead to technical and project readiness on the necessary time scales. Life-cycle and divestment costs will also be assessed. The fourth main WBS area is the system design of the SKA. The U.S. will contribute directly to the design via the efforts done under WBS areas 1-3, which will be integrated with working groups that are being organized by the SPDO. Major funding for the SPDO's design effort will come from the EC-funded SKA design project, PrepSKA.

Baseline Project

Primary Goals:

The scope of the TDP has been identified through

  1. consideration of local (U.S.) priorities for the direction of the SKA that have been identifed through community meetings;
  2. identification of a target timeline for the SKA project and for milestone events such as the next U.S. Decadal Survey and various design reviews; and
  3. identification of unique areas of R&D that are not being done elsewhere and which are critical to moving the project forward.

Overview of the Work Breakdown Structure:

TDP work is organized into four primary areas in a work-breakdown structure (WBS) that are listed in the order of specific technology R\&D followed by activities that aggregate knowledge gained to develop an SKA design:

In addition to specific work areas under these four WBS research and development items, the TDP will fund the management of the TDP, and it will fund work and activities that are crucial to U.S. involvement in the international SKA project and that ensure broad national participation in the project. These programmatic areas include: