Carbon Nanotubes for Wireless Communication and Radio Transmission

• US 20100144296A1
• Filed: 04/11/2008
• Published: 06/10/2010
• Est. Priority Date: 04/12/2007
• Status: Abandoned Application

• Current Assignee: Regents of the University of California (University of California)
• Original Assignee: Regents of the University of California (University of California)
• Inventors: Rutherglen, Christopher M., Burke, Peter J.
• Application Number:
  US12/594,927
• Publication Number:
  US 20100144296A1
• Time in Patent Office: Days
• US Class Current: 455/205
• CPC Class Codes: H03D 1/08 by means of non-linear two-pole elements H03D1/22, H03D1/26, H03D1/28 take precedence

Abstract

Described herein are systems and methods in which a carbon nanotube (CNT) is used as a demodulator of amplitude-modulated (AM) signals. Due to the nonlinear current-voltage (I-V) characteristics of a CNT, the CNT induces rectification of an applied RF signal enabling the CNT to function as a demodulator of an amplitude-modulated (AM) RF signal. By properly biasing the CNT such that the operating point is centered on the maximum portion of the I-V curve, the demodulation effect of the CNT can be maximized. The present invention is useful for possible nanoscale wireless communications systems, e.g., nanoscale radios.

Claims

1. A method for demodulating an amplitude modulated (AM) signal comprising:

applying the AM signal to a carbon nanotube to produce a demodulated signal; and

amplifying the demodulated signal.

2. The method of claim 1, further comprising feeding the amplified demodulated signal to a speaker.

3. The method of claim 1, further comprising voltage biasing the carbon nanotube.

4. The method of claim 3, wherein the carbon nanotube is biased at a bias voltage that is centered on a maximum nonlinear portion of a current-voltage (I-V) curve of the carbon nanotube.

5. The method of claim 1, wherein the amplitude modulation is within a frequency range of up to 100 kHz.

6. An amplitude modulated (AM) radio receiver comprising:

an antenna;

an AM demodulator coupled to the antenna, the AM demodulator comprising a carbon nanotube; and

an amplifier coupled to the AM demodulator.

7. The radio receiver of claim 6, further comprising a bias voltage source for biasing the carbon nanotube.

8. The radio receiver of claim 7, wherein the bias voltage source biases the carbon nanotube at a bias voltage that is centered on a maximum nonlinear portion of a current-voltage (I-V) curve of the carbon nanotube.

9. The radio receiver of claim 6, further comprising a speaker coupled to an output of the amplifier.

10. The radio receiver of claim 6, further comprising a sense resistor coupled to the nanotube for sensing a demodulated signal, wherein the amplifier is configured to amplify a voltage drop across the sense resistor.