Value chain · CLM-0999
In plain terms
Rockwell hung a small transmitter above the antenna to give every patch the same timing reference, and each patch corrected its own received timing back to what a perfectly flat antenna would see.
The claim as recorded
Rockwell's 1981 reference-phase distribution, stated as common to all its systems except the klystron "Reference Concept" (to be "converted to the common approach at a future time"), is free-space rather than cabled: a single shaped-beam illuminator at the rear of the aperture, at a height between half and three times the aperture diameter, feeds about 130,000 pick-up antennas, one per 5 m subarray, orthogonally polarised to the power dipoles, and a phase bridge and servo at each subarray normalise its received phase to that of a flat aperture held to +/-18 cm.
Evidence behind this: T3-contractor concept description; the databook says the pilot array and receiver designs were not available.
Scope and limits
A CONCEPT: "neither the exact design of the ground pilot array, nor that of the on-board pilot receiver antenna is available at this point" (printed 3-63). The illuminator's own stability and the free-space path's sensitivity to the aperture's shape are not analysed on these pages. SCOPE, from the same page (printed 3-60): the free-space approach is "common to all Rockwell systems, with the exception of the 'Reference Concept', i.e., one consisting of klystron-powered sub-modules", whose beam control "will be converted to the common approach at a future time"; so as of March 1981 Rockwell's own klystron reference concept was not yet on it. And the "~130,000 (one per 5-m subarray)" is a solid-state-antenna figure: it implies about 3.25 km2 of aperture (a 2.0 km diameter), not 1 km, and does not reconcile with the section's 1,588 mechanical 30 m modules (57,168 five-metre subarrays per antenna) unless it counts both antennas of the dual solid-state satellite; the page does not say.
What it assumes
No assumptions are recorded against this claim.
Where it comes from
Printed 3-60, transcribed from the render: the reference signal "originates from a single transmit location at the rear of the aperture"; pick-ups "orthogonally polarized with respect to the power dipoles" (normalised-verified); "structural integrity of the array aperture to within +/-18 cm flatness". Figure 3.1-45 (printed 3-57): "D/2 < H < 3D". Figures 3.1-50 and 3.1-51 (printed 3-61): "~130,000 pickup antennas (one per 5-m subarray)"; the phase bridge "drives a phase shifter until the path delay differential equals that of the reference standard".
Basis: illuminator height in aperture diameters; pick-up antennas per subarray
Related records
- Answers question
- QST-013 not published in this release
Cite this
energyaperture.com/c/clm-0999
CLM-0999, Energy Aperture, as of 1981.
Connected records
Other published records linked to this one. A list, not a judgement.
- Also from SRC-582
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