Gallium Arsenide and Gallium Nitride are preferred for LEDs, certain photovoltaics, and some very high frequency radio applications.

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Recent discoveries, however, have such medgadgets being powered by photons, hip hop and now high-frequency radio waves.

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Disturbance to satellite and high-frequency radio communications would cause them problems, also.

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Not all planes across oceans have data-link capabilities, and high-frequency radio is still used with some flights and as a backup with others.

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For decades, controllers relied on position reports over high-frequency radio every hour or so, competing for air time with fishing vessels and all kinds of other traffic.

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In the future, the product line will also include high-speed radio frequency and power-line connectivity solutions.

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This frequency is close to the lower band of the highest radio frequency band known as extremely high frequency which goes from 30 to 300 GHZ.

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High resolution is achieved by measuring motion rather than radio frequency signals as wifi does, and is based on where and how the person moves through an environment over time.

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The most interesting experiment is being done by Qantas at Sydney and Perth airports with high-tech frequent-flier cards that are embedded with an RFID (radio-frequency identification) chip.

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