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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¥ rotating rods, laboratory HFGW generation, and so forth is based upon the "jerk" or shake of mass (time rate of change of acceleration) and is derived by Baker (2006) as P = 1.76x1Q-52 (2r.M/6t) 2 W (1) where Pis the power of the GWs, W; r is the distance between two masses, m; Mis a change in force, N; over the time interval 6t, s; that is, the jerk or shake of the two masses, such as the change in centrifugal force vector with time; for example, as masses move around each other on a circular orbit. Figure 2 describes that situation. Please recognize, however, that M need NOT be a gravitational force (see Einstein, 1918; Infeld quoted by Weber 1964, p. 97; Grishchuk 1974). Electromagnetic forces are more than 1035 larger than gravitational forces and should be employed in laboratory GW generation. As Weber (1964, p. 97) points out: "The non-gravitational forces play a decisive role in methods for detection and generation of gravitational waves ... " Equation (1) is also termed "quadrupole formalism" and holds in weak gravitational fields (well over 100 g's), for speeds of the generator "components" less than the speed of light and for r less than the GW wavelength. This last restriction may not really apply. Certainly there would be GW generated for r greater than the GW wavelength, but the quadrupole formalism might not apply exactly. For very small 6t, the GW wavelength, AGw = c6t (where c ~ 3x 108 ms-1, the speed of light) is very small and the GW frequency VGw is high. As a numerical example, r is choosen to be 10 m (convenient laboratory size, though usually greater than AGw), M = 4x 108 N; for example, the force produced by a large number of piezoelectric resonators and M = 2x 10-10 s; equivalent to about a VGw = 5 GHz jerk or shake frequency so that AGw = 6 cm and P = 2.8x 10-13 W or 0.28 picowatts. Clearly a very small HFGW power is generated. GW GW AI [ A ~~----------8 ___ ! __ __._f...=Cf"---!Y fct r I I 8 I l 'I I I GW I T GW Figure 2. Change in Centrifugal Force of Orbiting Masses, dfct, Replaced by Change in Tangential Force, df,, to Achieve HFGW Radiation One of the first suggested means for the laboratory generation of HFGWs was the so called gaser analogous to the laser for light. Simply described (Halpern and Laurent, UNCLASSIFIED/ /FOR OEEICIJ.b HSI!! Dflti 3
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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.