What is Rectenna?

Rectenna is a rectic antenna, an antenna used to convert a microwave into a DC power supply. Since the antenna refers to any type of device that converts electromagnetic waves into electricity or vice versa, Rectenna is simply a microwave antenna, unlike the ubiquitous radio and television antennas. You probably saw the word rectenna that appeared in discussions on solar energy satellites or in other energy production schemes involving the transmission or radiation of microwave energy.

Rectennas are quite good in what they do: efficiency above 90% are quite common. Inverse rectennas, which convert electricity into microwave rays, are only in the early stages of development, with only about 1%efficiency. This is a problem for solar energy proposals.

There was some research involving the transmission of microwave power to obtain energy for community without wires. One of the obstacles for such research is the public view of microwaves as dangerous radiation,Through Association of Waves with microwave furnaces. However, the power densities used for the proposed microwave transmission systems are relatively low, similar to a conventional oven leak, and only slightly stronger than radiation generated by a mobile phone. Extensive studies of tens of thousands of employees in the electricity industry have shown that they do not experience an increased incidence of cancer or other diseases through the exposure to the waves, unlike the pseudo -scientific perspective exposed at the end of the 20th century.

Rectenna suitable for receiving energy rained from solar panels to geocentric orbit would have to be several kilometers across. Although the energy density of such an arrangement would be sufficiently low to avoid damage to people or the environment, there are some concerns about safety that energy on these platforms could be focused and used as energy Weapon, similar to Active deNIAL SYSTEM (ADS), AKA, "Ray of Pain" used in Iraq, but on a much larger scale. This could be prevented by building solar satellites in such a way that adjusting the focus of more than a small margin is mechanically impossible.