The Pentagon feared the frequency structure being demanded by Brussels in the so-called Upper L Band between 1559 and 1591MHz could have prevented American commanders from degrading navigation data in the theatre of war to all but their own forces, as is possible at present.

BBC: NEWS | Science/Nature | EU-US strike sat-navigation deal

The issue becomes just the latest in a long list of issues the SEC is examining regarding the current U.S. market structure, right up there with high frequency trading, dark pools, flash trading, market access, and trade tracking and reporting.

FORBES: SEC Takes Aim at Wild Market Swings

In reality, the markets (in part driven by privately held firms like Getco) have been evolving to a structure that caters to electronic trading, high frequency or otherwise.

FORBES: Out With the Old, In With the New

One photon in a million comes away with a different frequency from the one that it arrived with because it changes the structure of a chemical bond in one of the plastic's molecules.

ECONOMIST: Recycling

The other, which faces a specialised type of solar cell made of a material called indium gallium arsenide, is sculpted into a structure called a photonic crystal that causes it to emit infra-red radiation selectively at the frequency best absorbed by the cell.

ECONOMIST: Solar power