Summary

The year 2008 marks the 20th anniversary of the finalization of the design of the approximately 150 ground-based, mechanically rotating radars that comprise the Next Generation Radar (NEXRAD) network, known formally as the Weather Surveillance Radar 1988-Doppler (WSR-88D) network. This is the primary radar network in use by the National Oceanic and Atmospheric Administration’s (NOAA) National Weather Service (NWS) for operational surveillance of meteorological phenomena. The design of the newest systems of the nation’s civilian network of radars for aircraft surveillance and tracking, operated by the Federal Aviation Administration (FAA), was established at about the same time; some radars in the aircraft network were installed more than 40 years ago. This has prompted agencies including NOAA, the FAA, the Department of Defense (DOD) and the Department of Homeland Security (DHS) to undertake planning for possible upgrades to or replacing of these existing “legacy” systems.

The surveillance requirements and the possible applications of modern radar technology are many and varied across the key agencies. Different candidate replacement systems could be selected by individual agencies to fulfill their mission requirements. However, a potentially cost-effective approach would be to replace several legacy systems with a multifunction system designed to simultaneously meet the surveillance needs and mission requirements of several agencies. One such option, the Multifunction Phased Array Radar (MPAR), is the subject of this report.

In 2002, the Federal Committee for Meteorological Services and Supporting Research (FCMSSR) directed the Office of the Federal Coordinator for Meteorological Services and Supporting Research (OFCM) to explore federal needs and potential benefits of a phased array radar capability that would meet the mission requirements of several key agencies. In June 2004, OFCM established the Joint Action Group for Phased Array Radar Project (JAG/PARP), which subsequently issued the report Federal Research and Development Needs and Priorities for Phased Array Radar (OFCM, 2006). In 2007, OFCM requested that the National Research Council (NRC) review federal planning for an MPAR system, including a review of the JAG/PARP report and all relevant subsequent planning activities. Appendix A provides a detailed Statement of Task for the NRC committee that carried out this review.

PRINCIPAL FINDINGS

Phased array technology offers significant technical advantages for a next generation of weather and aircraft surveillance radars. A national implementation of approximately 350 MPAR radars could replace existing NWS and FAA radars and offer many performance advantages. Some technical, operational, and cost issues remain to be resolved. Also, there are some agency mission requirements that cannot be met by



The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement



Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.

OCR for page 1
Summary The year 2008 marks the 20th anniversary of the finalization of the design of the approximately 150 ground-based, mechanically rotating radars that comprise the Next Generation Radar (NEXRAD) network, known formally as the Weather Surveillance Radar 1988-Doppler (WSR-88D) network. This is the primary radar network in use by the National Oceanic and Atmospheric Administration’s (NOAA) National Weather Service (NWS) for operational surveillance of meteorological phenomena. The design of the newest systems of the nation’s civilian network of radars for aircraft surveillance and tracking, operated by the Federal Aviation Administration (FAA), was established at about the same time; some radars in the aircraft network were installed more than 40 years ago. This has prompted agencies including NOAA, the FAA, the Department of Defense (DOD) and the Department of Homeland Security (DHS) to undertake planning for possible upgrades to or replacing of these existing “legacy” systems. The surveillance requirements and the possible applications of modern radar technology are many and varied across the key agencies. Different candidate replacement systems could be selected by individual agencies to fulfill their mission requirements. However, a potentially cost-effective approach would be to replace several legacy systems with a multifunction system designed to simultaneously meet the surveillance needs and mission requirements of several agencies. One such option, the Multifunction Phased Array Radar (MPAR), is the subject of this report. In 2002, the Federal Committee for Meteorological Services and Supporting Research (FCMSSR) directed the Office of the Federal Coordinator for Meteorological Services and Supporting Research (OFCM) to explore federal needs and potential benefits of a phased array radar capability that would meet the mission requirements of several key agencies. In June 2004, OFCM established the Joint Action Group for Phased Array Radar Project (JAG/PARP), which subsequently issued the report Federal Research and Development Needs and Priorities for Phased Array Radar (OFCM, 2006). In 2007, OFCM requested that the National Research Council (NRC) review federal planning for an MPAR system, including a review of the JAG/PARP report and all relevant subsequent planning activities. Appendix A provides a detailed Statement of Task for the NRC committee that carried out this review. PRINCIPAL FINDINGS Phased array technology offers significant technical advantages for a next generation of weather and aircraft surveillance radars. A national implementation of approximately 350 MPAR radars could replace existing NWS and FAA radars and offer many performance advantages. Some technical, operational, and cost issues remain to be resolved. Also, there are some agency mission requirements that cannot be met by 1

OCR for page 1
2 EVALUATION OF THE MPAR PLANNING PROCESS replacing existing radars. These agency mission requirements relate primarily to low- level weather coverage and the ability to detect and track low-level, non-cooperative aircraft. The committee agrees generally with the five major findings in the Executive Summary of the JAG/PARP report (see Box S.1), with some exceptions. Regarding finding 2, the committee notes that some emerging requirements cannot be met with a network of 334 MPAR radars because there will be significant gaps in low-level and regional coverage. Regarding finding 4, the committee believes that the “preliminary cost evaluation” is promising, but embryonic. In addition, the basis for determining cost effectiveness of MPAR does not consider the cost effectiveness of other alternatives to the legacy systems, in addition to the legacy systems themselves. Similarly, regarding finding 5, the MPAR risk reduction program will also provide a basis for cost-benefit comparison to the other alternatives to legacy systems. BOX S.1 Findings from the Joint Action Group for Phased Array Radar Project (JAG/PARP) Report Finding 1: Multiple federal agencies currently rely on radar networks to provide essential services to the nation. The principal current uses are for weather surveillance and other atmospheric observations and for aircraft surveillance. Finding 2: A single MPAR network with the capabilities described in this report could perform all of the existing civilian radar functions. In addition, other existing and emerging needs not being adequately met by existing systems could be met with this same MPAR network. Finding 3: The timing is right to conduct a thorough evaluation now of MPAR as an alternative to conventional radar for the full range of current and emerging applications described in this report. The aging of our existing domestic radar networks for weather and aircraft surveillance will require substantial commitments of federal resources to either maintain or replace them. Finding 4: A preliminary cost evaluation shows that one MPAR network designed to meet multiple national needs can be developed, implemented, and maintained at a lower cost, on a life-cycle basis, than would be required to sustain the existing conventional radar networks through required maintenance and incremental upgrades. Finding 5: The JAG/PARP proposes a risk-reduction and development (R&D) plan that, for a modest investment, will provide a sound technical and cost basis for a national decision between MPAR implementation versus continued maintenance and upgrade of the aging, existing radar systems. The estimated total cost for this risk reduction plan is $215 million. The committee also agrees generally with Recommendations 1-4 in the Executive Summary of the JAG/PARP report (see Box S.2), but notes that even though Recommendation 4 calls for the FCMSSR to direct a cost-benefit analysis of the MPAR option and competing domestic strategies in conjunction with the MPAR risk-reduction program, this analysis is not explicitly found in Appendix D of the JAG/PARP report (the program plan). However, the Terms of Reference of the Working Group –MPAR (WG/MPAR Item 3b; OFCM, 2007) direct the working group to “[Perform] a cost benefit analysis to establish MPAR’s cost-effectiveness against alternative domestic radar options, considering both acquisition and total life-cycle costs.” For the JAG/PARP research plan to be effective, defined requirements and a national system architecture are

OCR for page 1
SUMMARY 3 required that will allow cost-benefit tradeoffs to drive the establishment of focused research objectives. The committee also believes that independent identification of alternative domestic radar strategies is needed. A thorough and independent cost-benefit analysis of MPAR and those alternatives would be in the nation’s best interest. BOX S.2 Recommendations from the Joint Action Group for Phased Array Radar Project JAG/PARP Report Recommendation 1: The FCMSSR should endorse the concept of an MPAR risk-reduction R&D program that substantially incorporates the objectives and the three components of the plan outlined in chapter 6 of this report. Recommendation 2: The FCMSSR should consider organizational options to foster collaborative and joint R&D on the MPAR risk reduction activities by establishing a joint entity, such as a Joint National Center for advanced Radar Research and Development, to manage agencies’ contributions to the risk reduction program outlined in this report. Recommendation 3: For the period prior to standup of a joint management entity, the FCMSSR should direct OFCM to form an interagency MPAR Working Group (WG/MPAR) within the OFCM infrastructure to coordinate and report on the R&D activities of participating agencies in implementing an MPAR risk- reduction program. Activities of the WG/MPAR should include, but not be limited to: • Identification of agency contributions to the first phase of risk-reduction activities in each component prong of the program. • Establish a cost basis for near-term agency contributions, sufficient to allow incorporation into agency budget submissions. • Explore options to foster interagency cooperation and collaboration on MPAR risk-reduction activities. • Develop a set of specific program progress metrics against which annual progress toward risk- reduction goals and objectives can be assessed. • Prepare and publish an annual statement of the next-year objectives and activities for the risk- reduction program. This annual statement should include a review of progress in the current year and connections to out-year activities and objectives, to show how each year’s activities contribute toward achieving the overall risk-reduction goals. As guidance to the participating agencies, the report should include an estimate of budget resources needed for the next-year activities and a summary of prior-year funding by agency. Progress toward goals and objectives, using the program metrics, should be reported each year, with an analysis of areas of shortfall and substantial progress. • Identify opportunities for review of program plans and progress by appropriate boards or study committees of the National Academies’ National Research Council. • Prepare and publish an MPAR Education and Outreach Plan to build understanding of and garner support for a national surveillance radar strategy decision within all the potentially affected federal agencies, Congress, state and local governmental entities, the private sector, and the public. This plan should involve the academic community and the media and include dissemination of results from the NRC studies suggested above. A series of workshops, coordinated through the National Center for Atmospheric Research (NCAR), should be considered for engaging the academic research community. Recommendation 4: The FCMSSR should direct that, in conjunction with the MPAR risk-reduction program, a cost-benefit analysis be undertaken to establish the cost-effectiveness of the MPAR option and competing domestic radar strategies. The basis for MPAR acquisition and life-cycle costs should include results from the technology development and test activities and the MPAR network refinement, as appropriate.

OCR for page 1
4 EVALUATION OF THE MPAR PLANNING PROCESS The committee’s recommendations are grouped below by general topic area. COMMITTEE RECOMMENDATIONS Overarching Recommendation The committee recommends that the MPAR Research and Development (R&D) program be continued with the objective of evaluating the degree to which a deployable MPAR system can satisfy the national weather and air surveillance needs cost- effectively. This program should incorporate the following features: • Full evaluation of the unresolved technical issues • An evaluation of the full operational requirements of all participating agencies and the ability of MPAR to meet these requirements • Development of the basis for reliable and realistic estimates of acquisition and lifecycle costs of a nationally deployed MPAR System • Independent assessment of the cost effectiveness of the R&D program itself, especially prior to commitment of major funding for the full-scale prototype. Specific Recommendations for the R&D Plan Recommendation: The R&D Plan outlined in Appendix D in the JAG/PARP Report should be expanded to provide detailed descriptions of the tasks to be undertaken, their priorities, the associated costs, and key decision points. Recommendation: The FCMSSR should seek a reasonable and continuous funding stream to support the R&D Program. Recommendation: The WG-MPAR planning process for the MPAR R&D program should implement frequent updating and improvement of the MPAR program plan to ensure planning robustness and relevance in the face of changing external conditions. As part of this WG-MPAR planning process, the program plan should be periodically evaluated against program goals and objectives, to ensure that these are both fully satisfied and remain relevant, and also the accomplishments of the R&D work. This evaluation should include annual external reviews, as suggested by Recommendation 3.5- 6 of the JAG/PARP report (see Box S.2). Recommendation: Probability estimates of the likelihood of success/failure of achieving objectives at critical decision points in the R&D program should be developed. Recommendation: The committee endorses Recommendation 2 of the JAG/PARP report and would like to see it implemented early in the program. The committee

OCR for page 1
SUMMARY 5 further recommends that the MPAR R&D program be as open as possible, in particular to ensure that interested parties from industry and universities are involved at early stages, and that the engineering development and scientific applications of the MPAR prototype benefit from involvement of the broadest communities possible. Recommendation: The MPAR R&D program should include the staged development of a prototype MPAR, proceeding through a Line Replaceable Unit (LRU), followed by a single antenna face, two faces, or a full four-faced prototype. Cost effectiveness studies should be carried out to determine how many faces would be required to assess the MPAR concept. Recommendation: The MPAR R&D Program, instead of developing new X- and C- band radars, should develop linkages with appropriate organizations within the radar community as a way to avoid duplication of effort and take full advantage of ongoing work related to short-wavelength radar technologies. Specific Recommendations on the Definition of Requirements Recommendation: The MPAR R&D program should produce a fully vetted set of technical performance requirements for an operational MPAR and radar network. To ensure robustness of the R&D Program in the face of potential re-balancing of stakeholder needs and participation over time, the MPAR planning process for non- weather surveillance should further emphasize the need to fully establish requirements of all participating agencies. Recommendation: MPAR system design studies and analysis of alternatives should consider the MPAR system as a candidate member of a family of systems, carefully considering design and mission tradeoffs with existing and new surveillance capabilities under development. Agencies must define clearly the role that MPAR will play toward meeting their needs and identify the supplemental sensing networks required to fully meet their needs. Recommendation: The Airport Terminal Area or T-MPAR concept needs to be developed in sufficient detail to demonstrate that mission requirements for terminal weather and aircraft surveillance can be met. In addition, the ability of a full MPAR to meet Terminal Doppler Weather Radar (TDWR) requirements must also be assessed due to the fact that the beamwidth would be approximately 1 deg (instead of ½ deg) and the frequency choice is S-band (instead of C-band). Specific Recommendations on Technical Issues Recommendation: The MPAR R&D program should produce a procedure for calibrating the reflectivity and polarimetric measurements at all scan angles. A key decision point for the feasibility of MPAR for weather surveillance, and continuance for

OCR for page 1
6 EVALUATION OF THE MPAR PLANNING PROCESS the R&D program, will be determination of its capability for dual polarization measurements. Thorough evaluation of the capability of phased array radar to accurately measure polarization variables independent of scan angle must be carried out early in the R&D program. Recommendation: Given the high demand for bandwidth at the proposed S-band frequency, the MPAR R&D program must determine the total required bandwidth as early as possible in the research program to ensure the feasibility of the design. Specific Recommendations on the Costs and Cost-Benefit Considerations Recommendation: A thorough and complete cost analysis of the total MPAR program should be performed and compared with historical life-cycle costs for the more recently and currently deployed systems such as ARSR-4 and ASR-11 that are roughly equal in performance to MPAR for air-traffic surveillance, and for NEXRAD and TDWR radars that provide a performance baseline versus MPAR for weather surveillance. A detailed baseline operations and maintenance (O&M) cost estimate should be determined for all legacy radar types to identify and quantify those highest cost radar types that are the prime candidates for life extension, upgrade or replacement. Independent cost risk analyses for the acquisition of MPAR and T-MPAR by recognized methods should be performed and frequently re-visited and updated. Recommendation: An alternative weather-only phased array weather radar design trade study and detailed cost analysis should be performed and compared with historical life cycle costs and performance for NEXRAD and TDWR radars. This trade study and cost analysis should be compared with a more detailed MPAR cost analysis and trade study to determine if the marginal cost of adding the required aircraft surveillance capability is worth the perceived benefit of having an all-in-one system.