Value chain · CLM-1091
In plain terms
The people running the programme said 2.45 GHz was sensible and also said, in the same breath, that nobody international had agreed to it and the choice was open. Their own account of the 1979 world radio conference is that no frequency was given and one might be, if the environmental case were made.
The claim as recorded
Inside the programme the choice was described as reasonable and not final. The 1979 radio astronomy workshop: "The beam center frequency choice of 2.45 GHz is a reasonable one from many viewpoints. Nonetheless, no international frequency assignment has been made, and this choice cannot yet be considered final." The 1977 ionosphere study: "The choice of frequency, aside from the political and frequency allocation aspects, depends on a common scale of values applied to the ionospheric and tropospheric impacts. The ionospheric effects argue for a higher frequency" and "In the meantime, a clear choice cannot be made." The 1980 Boeing summary reports the 1979 WARC: "no frequency was assigned but it was ruled that the U.S. could have such an assignment if the SPS is proven environmentally safe by further research." TM-58236's reference guidelines "did not rule out the consideration of alternatives".
Evidence behind this: T3-programme and contractor statements of the choice's status, 1977-81, one of them a second-hand account of WARC-79 with no WARC document cited.
Scope and limits
THE WARC STATEMENT IS ONE PARAGRAPH OF A CONTRACTOR'S CONFERENCE SUMMARY WITH NO WARC DOCUMENT CITED; it records what the programme believed in January 1980 and is not evidence of what WARC-79 decided. CLM-0919's limits leave the WARC outcome open and this does not close it. The 1977 study's "clear choice cannot be made" is conditional on cost data it says did not then exist.
What it assumes
No assumptions are recorded against this claim.
Where it comes from
PDF p.37 / 20, NORM, both sentences. SRC-108 PDF p.9 / 1-2, NORM, all three spans, and "Half or more of the SPS power at either frequency may be lost to the rectenna through a hailstorm with large, wet stones." SRC-551 PDF p.28 / 18, render, TRANSCRIBED (text layer "'Vas" for "was"): "Frequency allocation for SPS was discussed at the 1979 WARC; no frequency was assigned but it was ruled that the U.S. could have such an assignment if the SPS is proven environmentally safe by further research." SRC-554 PDF p.30 / 20, render, TRANSCRIBED, the guidelines sentence.
Related records
- Answers question
- QST-017 not published in this releaseQST-019 not published in this release
Cite this
energyaperture.com/c/clm-1091
CLM-1091, Energy Aperture, as of 1977-1981.
Connected records
Other published records linked to this one. A list, not a judgement.
- Also from SRC-108
- CLM-0043The study the 1978 reference system cites put the level where the beam may start to disturb the ionosphere at about 20 milliwatts per...CLM-0045The apparent conflict between 12 and 23 was not an error. The underlying study gave a range, and the figure adopted sits near the top of it.CLM-0066The figure adopted in 1978 was higher than each of the lower figures in the studies it cited, though those figures were themselves...CLM-0072The 1978 study gives 12 milliwatts per square centimetre for runaway, give or take a factor of two, and says no threshold can be set in the...CLM-0082The formula is the right one for the conditions space solar power would create. It was written for this case, not borrowed from a different...CLM-0083The formula is the right type but nobody has said how far it can be pushed, and at space solar power frequencies the wave is about 200...CLM-0085The 1978 formula does not give a threshold. It relates threshold power to the width of the plasma structures produced, so getting a single...CLM-0101The 1978 contract required the researchers to report fixes if ionospheric disturbance pushed the pilot-beam phase error past 2 to 3...More on the source page.
- Also from SRC-516
- CLM-0988The rule that radio astronomers hold the satellite to is a specific international report, and its limit near the satellite's frequency is...CLM-0989The same figure, minus 160, appears in two 1970s papers meaning two different things: in one it is the noise reaching the ground, in the...CLM-0990The extra twenty decibels of noise suppression for a fleet assumes a hundred satellites. The government's reference plan was sixty, which...CLM-0991In 1978 the frequency band the satellite was to use was an industrial free-for-all band in the West, where users must put up with each...CLM-0992The receiving field on the ground makes its own harmonics: the diodes that turn microwaves into electricity also generate signals at two...CLM-1222The fourth paper the 1978 design cites for its beam limit also calls the limit a theory that had not been tested. The one experiment it...
- Also from SRC-551
- CLM-1088By 1980 the programme remembered its first study as having picked 2.45 GHz. The first study's report says it picked 3.3 GHz. The 2.45 GHz...CLM-1090The programme's two printed tables of how much beam the weather eats do not agree. One has the ionosphere numbers the wrong way round, and...CLM-1408In the late 1970s, US studies sketched receiving stations raised on posts or legs so the ground beneath could still be farmed or built on...
- Also from SRC-554
- CLM-0911If the steering signal from the ground stops, the 1978 design's beam does not carry on pointing somewhere. It falls apart, and the power on...CLM-1017By 1981 the programme itself said the ionospheric limit it had designed to was probably too cautious, and worked out what relaxing it to...CLM-1018Three years of study left the efficiency chain exactly where 1978 put it, and Boeing's own version says out loud the solar constant the...CLM-1019The programme gave three reasons for choosing the klystron; the company that designed the satellite said the choice was more or less...CLM-1020By 1981 the programme was confident the beam could be pointed and formed, and named the network that carries the timing reference across...CLM-1022A loss you can make up by adding solar panels costs about 56 million dollars per percentage point; a loss at the ionospheric ceiling costs...CLM-1087When the programme wrote down why it used 2.45 GHz, its reasons were consistent: each time it named the industrial band and how the beam...CLM-1478Almost everything that can go wrong with this design makes the beam fall apart and become harmless, which is the right way to fail. Two...