Value chain · CLM-0511
In plain terms
The first real, built, and measured version of CASSIOPeiA's beam-steering hardware converts electricity to radio power at 42%, against about 80% for the amplifier alone and 65% for the amplifier with its circulator, once every real component is counted rather than just the amplifier chip.
The claim as recorded
A fabricated 112-element cross-helix retrodirective array (the CASSIE grant's own hardware deliverable, Queen's University Belfast/Imperial College London, academically independent of Ian Cash/Space Solar/International Electric Company) achieved a measured system-level DC-to-RF efficiency of 42% once the full retrodirective unit cell (phase-locked loop, driver, circulator, DC-DC conversion) is counted, against the same authors' earlier report of a power-amplifier drain efficiency close to 80% (75% at 6 W without the circulator) and 65% for the amplifier with its circulator (SRC-001 PDF p.6-7, printed p.5-6); the paper states reaching 80% at the unit-cell level "would not be trivial." No mass or areal-density figure is stated anywhere in the paper.
Scope and limits
Tested at 112 elements, 1m2 rectenna, 6.5m range, roughly six and a half to eight orders of magnitude below the scale a real CASSIOPeiA system needs (672 W RF against 2 GW is about 6.5 orders; a 1 m2 rectenna against the paper's projected 6.7 km x 13 km farm is about 7.9 orders; SRC-001 PDF p.2); no end-to-end DC-to-DC efficiency was measured because the borrowed test rectenna's polarisation did not match the array's linear polarisation.
What it assumes
No assumptions are recorded against this claim.
Where it comes from
PDF p.6 (printed p.5): "12.7 W is required to give 6.35 W of RF power, which equates to a DC-RF Efficiency of 50%"; "The total DC power into the DC-DC converter was measured as 15.11 W, which reduces the overall DC-RF efficiency to 42%"; "the power amplifier used in the phase conjugating unit cell has a drain efficiency close to 80% [16]"; "it would not be trivial to obtain efficiencies of this level". PDF p.7 (printed p.6): "Knowing that the overall PA and circulator efficiency is 65%"; "this showed the majority of unit cells to be in the region of 42% DC to RF conversion efficiency, with several units reaching close to 45 % conversion efficiency".
Basis: measured DC-to-RF efficiency, 112-element fabricated array, W/element
Related records
- Answers question
- QST-002 not published in this release
Cite this
energyaperture.com/c/clm-0511
CLM-0511, Energy Aperture, as of 2026.
Connected records
Other published records linked to this one. A list, not a judgement.
- Also from SRC-001
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