Nanoradio
Encyclopedia
A nanoradio is a radio
receiver or transmitter constructed on a nanometer scale. Currently only receivers have been developed and they are structured around a carbon nanotube
. The first such device was described in October 2007 by a team led by physicist Alex Zettl
.
The nanotube, about 10 nanometers in diameter and several hundred nanometers long, is contained in a vacuum
and one of its ends is connected to an electrode of a battery. The other electrode is placed a short distance from the nanotube's other end. The tube, now charged, will vibrate in tune with any external electromagnetic signal, effectively acting as an antenna
. The favorable vibration frequency can be adjusted by changing the applied voltage, which allows to tune
the radio to different carrier frequencies
. The field electron emission effect causes a current to flow, as electrons tunnel across the gap between the tube and the second electrode. This current represents an amplified
version of the radio signal; no demodulation
is necessary.
Radio
Radio is the transmission of signals through free space by modulation of electromagnetic waves with frequencies below those of visible light. Electromagnetic radiation travels by means of oscillating electromagnetic fields that pass through the air and the vacuum of space...
receiver or transmitter constructed on a nanometer scale. Currently only receivers have been developed and they are structured around a carbon nanotube
Carbon nanotube
Carbon nanotubes are allotropes of carbon with a cylindrical nanostructure. Nanotubes have been constructed with length-to-diameter ratio of up to 132,000,000:1, significantly larger than for any other material...
. The first such device was described in October 2007 by a team led by physicist Alex Zettl
Alex Zettl
Alex Zettl is an American professor of experimental condensed-matter physics. His research involving the properties of novel materials have produced significant advances in the field.-Biography:...
.
The nanotube, about 10 nanometers in diameter and several hundred nanometers long, is contained in a vacuum
Vacuum
In everyday usage, vacuum is a volume of space that is essentially empty of matter, such that its gaseous pressure is much less than atmospheric pressure. The word comes from the Latin term for "empty". A perfect vacuum would be one with no particles in it at all, which is impossible to achieve in...
and one of its ends is connected to an electrode of a battery. The other electrode is placed a short distance from the nanotube's other end. The tube, now charged, will vibrate in tune with any external electromagnetic signal, effectively acting as an antenna
Antenna (radio)
An antenna is an electrical device which converts electric currents into radio waves, and vice versa. It is usually used with a radio transmitter or radio receiver...
. The favorable vibration frequency can be adjusted by changing the applied voltage, which allows to tune
Tuner
Tuner may refer to someone or something which adjusts or configures a mechanical, electronic, or musical device.- Electronic :* Antenna tuner, a device to adjust the resonance frequency of an antenna or transmission line...
the radio to different carrier frequencies
Carrier wave
In telecommunications, a carrier wave or carrier is a waveform that is modulated with an input signal for the purpose of conveying information. This carrier wave is usually a much higher frequency than the input signal...
. The field electron emission effect causes a current to flow, as electrons tunnel across the gap between the tube and the second electrode. This current represents an amplified
Amplifier
Generally, an amplifier or simply amp, is a device for increasing the power of a signal.In popular use, the term usually describes an electronic amplifier, in which the input "signal" is usually a voltage or a current. In audio applications, amplifiers drive the loudspeakers used in PA systems to...
version of the radio signal; no demodulation
Demodulation
Demodulation is the act of extracting the original information-bearing signal from a modulated carrier wave.A demodulator is an electronic circuit that is used to recover the information content from the modulated carrier wave.These terms are traditionally used in connection with radio receivers,...
is necessary.