Value chain · CLM-1124
In plain terms
One panel the size of a sheet of paper turned about seven-tenths of the microwave power landing on it into DC, and did best at about three hundred watts per square metre, a little over half the highest level tested.
The claim as recorded
One 203-element, 181 x 256 mm tile of the NRL 2022 array, at the target centre with the incident density swept "over a 98 to 524 W/m2 range" into a 180 ohm load, gave "16.5 W output power" at "a power density of 522 W/m2, corresponding to an RF-to-DC conversion efficiency of 68%", and "A peak efficiency of 71% is achieved at a power density of 304 W/m2", the efficiency being output power divided by the total power incident on the tile surface; the authors call the single-tile result "not statistically representative".
Evidence behind this: T1-peer-reviewed measured tile efficiency, single specimen, the authors' own "not statistically representative".
Scope and limits
ONE TILE, ONE SWEEP, NO STATED UNCERTAINTY; the authors' own caveat is in the claim. The 180 ohm load is the tile's, not the array's 30 ohm; the peak at 304 W/m2 rather than at the top of the range is a load-matching effect the paper does not analyse. Pulsed conditions as in CLM-1123.
What it assumes
The incident density is the calibrated-horn map at the tile position (CLM-1125's stated error source applies here too).
Where it comes from
PDF 9 / printed 36: "sweeps over a 98 to 524 W/m2 range" (normalised); "measured output power across a 180" (normalised) ohm load; the paper reports 16.5 W of output at 522 W/m2, an RF-to-DC efficiency of 68 per cent, while calling the sample not statistically representative (R1); "A peak efficiency of 71% is achieved at a power density of 304 W/m2" (R1); the definition: efficiency is the output power divided by the total power incident on the surface of the rectenna tile (normalised). Recomputed: 0.181 x 0.256 = 0.04634 m2; 522 x 0.04634 = 24.19 W incident; 16.5 / 24.19 = 0.682; at 304 W/m2 and 71 per cent, 0.71 x 304 x 0.04634 = 10.0 W; sqrt(16.5 x 180) = 54.5 V and 0.30 A at the tile, 4.5 V per row and 18 mA per element.
Basis: W; W/m2; ohm; per cent RF-to-DC (DC output / incident power on the tile surface)
Related records
- Answers question
- QST-002 not published in this release
Cite this
energyaperture.com/c/clm-1124
CLM-1124, Energy Aperture, as of 2022-01.
Connected records
Other published records linked to this one. A list, not a judgement.
- Also from SRC-270
- CLM-1122About twenty thousand postage-stamp-sized antenna-plus-diode cells, each with an off-the-shelf microwave diode, wired into tiles, then...CLM-1123A five-metre dish and a 100 kW radar-type pulsed tube a kilometre away, bounced partly off the ground on purpose to get more power onto the...CLM-1125Four square metres of receiver turned 73 per cent of the microwave power arriving at it into 1.65 kW of DC, measured a kilometre from the...CLM-1126They deliberately fried each of the four panels with ever-stronger pulses. A bare panel gave up at 672 watts out; clamping its voltage with...CLM-1127As flown, under two per cent of the microwave power fed to the dish came out of the receiver as electricity, because the beam had to be...CLM-1128A second test used a big radar dish in Massachusetts to light up a strip of LEDs on a tower over a kilometre away, with about a kilowatt...CLM-1129The authors say the 1975 record still stands at twenty times their power, that the custom diodes which set it no longer exist, and that...CLM-1130A quick way to size a ground-to-ground beam: at the distance where the dish stops focusing, the cone holding half the power is about twice...More on the source page.