Documents / Report
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.
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"labeled" as whatever is recovered from the receivers at the same frequency as (and
indeed phase-locked to) the modulation, so therefore the PPF can be distinguished from
scattered BPF very easily. Typically a lock-in amplifier (referenced to the field
modulation) is used to recover the signal in such an arrangement, which provides
significant noise rejection by effectively reducing the detection bandwidth.
D01.3 Microwave Transmitter {Gaussian beam)
Design of the microwave transmitter for the Gaussian beam, directed towards the
central fractal membranes: Dr. R.C. Woods (LSU) + graduate student, Dr. R. M L
Baker (TSC), G.V. Stephenson (TSC). This is expected to require 10 to possibly
10,000W (1,000W nominal) at around 10GHz, with an associated power supply and
appropriate safety interlocks. Possible technologies include solid-state, magnetron,
traveling-wave tube (TWT), or high-power klystron, and specifications will be developed
under this component of the work. These are all mature technologies and commercial
units will suffice. Possible suppliers include: Microwave Power Inc. (Santa Clara,
California; solid-state, up to 500W); ETM Electromatic Inc. (Newark, California; TWT or
klystron, up to 10kW); and Toshiba Electron Tube and Devices Co., Ltd. (Japan; TWT or
klystron, over 10kW). Generally speaking, wideband solid-state amplifiers produce less
output power than medium bandwidth models or narrow-band tube designs, so that the
compromise here will be to decide whether to accept lower power in favor of wide
tunability. Also required is a suitably matched transmit antenna. Again, commercial
designs will suffice, such as those from Rozendal Associates Inc. (Santee, California),
ETS-Lindgren (Cedar Park, Texas), or Orban Microwave Products (El Paso, Texas). The
compromise that must be worked out in the antenna design is that a high-gain antenna
is needed to constrain the GB to be within the resonance cavity or interaction volume
(so that microwave input power is not wasted), but a high-gain antenna is less tunable
than a broadband low-gain antenna. As in other work areas of this proposal, the
complete design will need to establish the cost-performance tradeoff issues surrounding
the various approaches.
D01.4 Fractal Membranes and Microwave Absorbers
Design of the fractal membranes as microwave reflectors/absorbers at select
frequencies (Wen et al., 2002; Zhou et al., 2003) and other high-performance
microwave absorbers: Dr. R. ML Baker (TSC), G.V. Stephenson (TSC).
DDl.4.1 Design of the fractal membrane (FM) reflectors at the waist of the
Gaussian beam including their paraboloidal form. An analysis will be completed to
determine the optimal material of the FMs (copper, stainless steel, or aluminum are the
obvious leading candidates). A paraboloidal surface will be designed that can be
fabricated from the FM to focus the PPF at the planned locations of the microwave
receivers. Hong Kong University of Science and Technology can fabricate the fractal
membranes out of these metals in almost any form.
DDl.4.2 The interior of the containment vessel (except for an opening at the
Gaussian-beam transmitter end) must be treated to eliminate exterior sources of noise.
Either a Faraday Cage (using a mosaic of HTSC tiles; for example, YBCO) or fractal
membranes are possibilities. Both will be examined in detail to determine the optimal
approach. A design compatible with the containment vessel shape (DD1.1.4) and
placement of interior detector elements will be developed.
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Report, from the dia 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.