This enables the HDVD 800 to transmit the entire frequency spectrum of high-end audio sources without any loss of frequencies.

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These leads will have to be sufficiently short to transmit very high frequency signals, which tend to radiate away as microwaves if the lead is too long (by 2015, chips will work high in the gigahertz band).

ECONOMIST: MONITOR

ADS-B promises to make air traffic control easier, cheaper and in many ways safer by allowing planes to transmit their locations by radio frequency instead of depending on towers to use radar to track and coordinate them.

FORBES: Next-Gen Air Traffic Control Vulnerable To Hackers Spoofing Planes Out Of Thin Air

One such project is called NewsFlash, and uses high-frequency red and green light to transmit data to the built-in camera on a receiving device -- in this case Samsung's Epic 4G.

ENGADGET: NewsFlash uses high-frequency light to transmit data from iPad to smartphone, we go hands-on (video)

But those bootleg versions have a more limited frequency range and can only receive signals, not transmit them.

FORBES: DARPA-Funded Radio HackRF Aims To Be A $300 Wireless Swiss Army Knife For Hackers

Their basic concept is to use light to transmit the quantum information using interferometers, which are instruments that change the frequency of light waves, then recombine them to get particular effects.

FORBES: The Air Force Is Working On A Holographic Quantum Computer

They could be used to make cheap radio-frequency identity tags in essence, printable bar-codes that transmit an identifying code in response to a pulsed radio signal.

ECONOMIST: Just press print

The concerns stem from the emissions of radio frequency (RF) radiation by both the handsets and the base stations that transmit and receive the signals.

BBC: Public Petitions Committee

Although they have not been found to cause any harm, the cables on conventional pylons, which transmit a three-phase alternating current, generate a strong electric field and a continuous buzz of low-frequency radio waves.

ECONOMIST: Monitor