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Defense Intelligence Reference Document High-Frequency Gravitational Wave Communications

Defense Intelligence Agency · 57 pages · text from the file's own layer

This Defense Intelligence Reference Document was prepared by the Defense Intelligence Agency under its Advanced Aerospace Weapon System Applications (AAWSA) program, is dated 6 April 2010 and is part of a series of advanced technology reports produced in FY 2009. It reviews proposed laboratory generators and detectors of high-frequency gravitational waves for communications. It favors an infrared-excited molecules transmitter and the Li-Baker detector, estimating about 1.9 million bits per second over 7,000 km through the Earth. It also discusses timing standards and interplanetary navigation uses.

  • p. 3 …the FTS Devices ............................................. 30 3.4.1 Propagating Signals From Optical Lattice Clocks for Timing ................ 31…
  • p. 4 …Omni-Directional Nature of the HFGW Radiation Pattern ....................... 10 Figure 8. Predicted Relic GW Energy Density…
  • p. 5 …The Piezoelectric Approach to HFGW generation is best for the proof-of- concept test and the…
  • p. 6 …Antennas, cables, and phone lines would be things of the past. A timing standard alone, provided…
  • p. 8 …over the time interval !1t, s; that is, the jerk or shake of the two masses…
  • p. 9 …The usual difficulty with HFGWs generated by nuclear reactions is the small dimensions of their nuclear…
  • p. 22 …the initial momentum uncertainty, dt is the time of the future measurement, and m is the…
  • p. 23 …Eis the effective energy contained within the detector cavity summed over the detection averaging time, and…
  • p. 24 …The temporal quality factor in the Li-Baker detector arises from averaging the signal over time…
  • p. 28 …Another way to increase Q is to arbitrary increase sample times of the signal. This technique…
  • p. 29 …There is also a hidden integral here which occurs over the sample time, which is understood…
  • p. 30 …3.3 FREQUENCY AND TIME STANDARD The first application of HFGW to the distribution of frequency…
  • p. 31 …The arrival times of the received PPS signals could be compared via time difference of arrival…
  • p. 32 …The universal nature of the HFGW frequency and time standards are especially helpful. The following telecommunication…
  • p. 33 …the search space is reduced, speeding acquisition. • Ultra-fast acquisition allows more efficient TDMA, or Time…
  • p. 34 …For a 5 μsec acquire test time, the result is Tacq = 150 x 150 x 16…
  • p. 35 …At this precision one could measure the time delay caused by changing once centimeter in height…
  • p. 36 …the problem of mapping the positions of the Lagrangian points, which vary slightly over time. 3…
  • p. 38 …As prototypes show promise they could be transitioned to device development, the first time that industry…
  • p. 39 …For instance, if there were one GW source on Earth, and one GW source on the…
  • p. 41 …Nonlinearity improves the focusing process and h goes to one in finite time, producing a singularity…
  • p. 45 …and Stephenson, G.V. (2007), "The Value Estimation of an HFGW Frequency Time Standard for Telecommunications…
  • p. 46 …Thesis, The University of Birmingham, January. Kippenberg, T. J. and Vahala, K. J. (2008), "Cavity Optomechanics…
  • p. 49 …time of future measurement, s effective energy contained within the detector cavity summed over the detection…
  • p. 50 …The project plan and timing are described below under separate headings for each component of the…
  • p. 51 …coils that superimpose upon the constant applied magnetic field a time-varying component at low frequency…
  • p. 53 …photon events, and has very good time resolution. The disadvantage is its cost and complexity. This…
  • p. 55 …Cryogen-free (more accurately, the cryogen is completely enclosed and re-cycled each time the magnet…
UNCLASSIFIED//F811. 8FFll!l*L 1!1!11! 8HL"i'
1964), the gaser consists of a long rod of a material and microscopic parts of which can
be excited by a means, such as electromagnetic (EM) radiation, to emit HFGWs. They
utilize linearized theory to treat the interaction of a gravitational field with matter:
"Application is made to the emission ... of gravitons by microscopic systems such as
molecules and nuclei." Grishchuk and Sazhin in early 1974 discussed the emission of
gravitational waves by an electromagnetic cavity. In August of 1974 Chapline, Nuckolls
and Woods suggested the generation of HFGWs by nuclear explosions. In this same
regard Fontana suggested that the problem of efficient generation of HFGWs and pulses
of gravitational radiation might find a reasonably simple solution by employing nuclear
matter (Fontana and Baker, 2006; Fontana and Binder, 2009), especially isomers. A
fissioning isomer not only rotates at extremely high frequency(~ 3.03x10 24 s- 1 )
according to the aforementioned references, but is also highly deformed in the first
stages of fission (the nucleus is rotating and made asymmetric "before" fission). Thus
one achieves significant impulsive forces (for example, 3.67x 108 N) acting over
extremely short time spans (for example, 3.3x10- 22 s). Alternatively, a pulsed particle
beam, which could include antimatter, could trigger nuclear reactions and build up a
coherent GW as the particles move through a target mass. The usual difficulty with
HFGWs generated by nuclear reactions is the small dimensions of their nuclear-reaction
volumes-that is, the small moment of inertia and submicroscopic radii of gyration (for
example, 10-16 m) of the nuclear-mass system. Such a difficulty is overcome by utilizing
small clusters of nuclear material, whose nuclear reactions are in synchronization; for
example, through the use of a computer controlled logic system. Such nuclear-
energized HFGW generators are currently very theoretical. Braginsky and Rudenko
(1978) discussed the generation of gravitational waves in the laboratory and proposed
a means utilizing small particles In 1981 Romero and Dehnen analyzed the generation
of gravitational radiation in the laboratory also utilizing a linear array of piezoelectric
crystals that will be analyzed in more detail in Section 2.1.3. In 1988 Pinto and Rotoli
presented a paper on the laboratory generation of gravitational waves at the Italian
Conference on General Relativity and Gravitational Physics. Another Italian, Giorgio
Fontana (1998), suggested that the possibility of emission of high frequency
gravitational radiation from junction between d-wave and s-wave superconductors.
Kraus (1991) proposed that gravitational-wave communication might be possible in the
IEEE Antennas & Propagation magazine. At the first HFGW Working Group Conference
at the MITRE Corporation in 2003, Grishchuk analyzed electromagnetic generators and
detectors of gravitational waves. At that same Conference Valentin Rudenko presented
a paper on the optimization of parameters of a coupled generator-receiver for a HFGW
Hertz experiment. At the second HFGW Working Group Conference in Austin, Texas, in
2007, Kolosnitsyn and Rudenko presented another paper on the generation and
detection of the high-frequency gravitational radiation in a strong magnetic field. In
2007, and more recently this year, a new type of HFGW generator/detector and mirror
system based on thin, type I superconducting films was proposed by R. Chiao, S.
Minter, and K. Wegter-McNelly (2007; 2009a,b). Therefore it is evident that a number
of devices for the laboratory generation of HFGWs have been proposed including the
aforementioned gaser (as has been mentioned, was first proposed by Halpren and
Laurent in 1964, some 45 years ago) discussed by Fontana and Baker (2003); as well
as an actual laser generator of HFGWs as discussed by Li and Li (2006). Finally a rather
practical laboratory HFGW generator, which may be appropriate for the initial proof-of-
concept test, is one utilizing off-the-shelf components such as magnetron energized
piezoelectric crystals or Film Bulk Acoustic Resonators or FBARs has been analyzed in
Woods and Baker, (2005) and Baker, Woods and Li (2006).
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Report, from the dia collection. The PDF is mirrored here; the original link is under it. 57 pages are in the text index: search them above, or from the library's search.