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This Defense Intelligence Reference Document, DIA-08-1004-005, is dated 6 April 2010. The Defense Intelligence Agency's Defense Warning Office prepared it under the Advanced Aerospace Weapon System Applications program. It reviews proposed laboratory generators and detectors for high-frequency gravitational waves. It favors a piezoelectric approach for proof-of-concept tests, IR-excited molecules for an operational transmitter and the Li-Baker detector as the receiver. It estimates about 1.9 million bits per second over 7,000 km through the Earth and discusses timing standards and interplanetary navigation uses.
From the source:Release of 2026-09-18 Incident: 4/6/10, Las Vegas, Nevada. Released with redactions. This document is a Defense Intelligence Reference Document (DIRD), a technical reference format used by the Defense Intelligence Agency (DIA) to capture baseline knowledge on a specific topic for later analytic use. DIRDs are best understood as reference and synthesis products rather than as original research. It is one of 38 DIRDs produced under the Advanced Aerospace Weapon System Applications Program (AAWSAP) between 2009 and 2011. Because AAWSAP’s scope permitted a broad range of supporting topics, not every DIRD in the series directly concerns aerospace systems or future threat assessment. The following summary reflects the DIRD’s scope and framing at the time of writing and should not be read as implying current validation of the concepts discussed. This DIRD examines whether high-frequency gravitational waves could serve as a communications medium while avoiding the attenuation that limits radio-frequency systems. The report surveys proposed transmitter and detector concepts, argues that gravitational-wave communications could support secure point-to-point links, timing standards, and interplanetary navigation, and gives particular attention to laboratory generator concepts and the Li-Baker detector as possible building blocks for such a system. The document makes clear, however, that the entire concept depends on capabilities that had not been demonstrated in practice, including laboratory-scale generation and reliable detection of usable high-frequency gravitational-wave signals. It is an exploratory systems-oriented review built around a future communications concept.
UNCLASSIFIED//EOR OEEICI0L Llili QI\IL¥ quantitative estimate would be needed to ensure that the non-uniformity is not serious in the present appl ication, but this is not expected to be a problem since field non uniformity just produces non-uniform PPF generation in the interaction volume. The fracta l membrane reflectors would still focus all the PPF at the receivers. The design tradeoff will be whether one or two large magnets are more cost-effective than a larger number of sma ller magnets. The design effort will be divided into two major sub-tasks: off-the -shelf electromagnets currently available, and emerging -technology proposed magnets that may become available during the construction phase of the HFGW detector. DDl.7.1 Off-the-shelf hardware: Excepting major installations, iron-core magnets are limited to around 2T over small volumes so that superconducting magnets are expected to be used here. Cryogen-free (more accurately, the cryogen is completely enclosed and re-cycled each time the magnet is cooled for use) superconducting magnets producing fields up to 16T are available commercia lly from a number of manufacturers including Scientific Magnetics, Oxford Instruments, and Cryogen ic Ltd. (all UK). As examples, Oxford Instruments can supply magnets producing 9T in a 20cm bore, and ST in a 1m bore. Typica lly, cooling is provided by an integral Gifford McMahon cryo-cooler at 4.2K. Use of a cryogen-free "dry" magnet means that there are no cold seals to be a source of leaks. DDl.7.2 Emerging technology: Since the detection PPF signal is directly proportional to the static magnetic field value, the detector sensitivity will be increased by using larger fields than currently-avai lable commercial designs permit. To this end we will investigate the feasibility of co-developing with a third-party (for example, National High Magnetic Field Laboratory, Tallahassee, Florida) a custom-made high-field design capable of up to 35T (Bird, 2004), which may be real izable during the construction phase of the Li-Baker detector. If successful, ach ieving this value of magnetic field would improve the sensitivity of the Li-Baker detector by an order of magnitude. In this case, if a separate refrigeration system is required, the specification would include cryogen level-monitoring to ensure safe auto-rundown of the superconducting magnet if the helium level falls below a pre-set value, to reduce the danger associated with cryogenic -system related magnet failure .. I Systems Engineering Tasks Following the completion of the Li- Baker detector development tasks, plans and specifications will be drawn up by LSU in collaboration with TSC. Since overlap of tasks is possible, approximately 18 months will be allowed for the detector design, and approximately 8 months for the preparation of plans and specifications. With approximately two months overlap of the major tasks, a total of two years will be schedu led for the detector's design and development of the plans and specifications. Fig. 4.1a shows a Gannt chart for scheduling the project. For any large engineering project, coordination among investigators is important for the development of a coherent, unified design . This is the role of systems engineering tasks, depicted at the top of Fig. 4.1a. In the present case, the development of the detector will demand the close coordination of the detection link budget very early on, in order to carefu lly guide the component design for each of the component areas, and to ensure that the sensitivity goals can be met. This task culm inates in a review of the predicted signal-to noise ratio. A follow-on to this task is the development of key component requirements Interface requirements development is the next level of detail in systems engineering UNCLASSIFIED/ /FOR OEEICIJ.b HSI!! Dflti 50
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Official release, from the pursue collection. The PDF is mirrored here; the original link is above. 57 pages are in the text index: search them above, or from the library's search.