Characteristics of an atmospheric discharge plasma as an RF antenna
Abstract
The plasma produced by a laser-guided, electric discharge in the atmosphere has been formed in the shape of a folded monopole antenna with a characteristic frequency of 112 MHz. This plasma antenna has been used to transmit and receive signals at 112 MHz. While the plasma conductivity remained above a certain value, the signal transmitted from, and received on, the plasma antenna was within -l + or - 1 dB of that transmitted from and received on a 'standard' copper folded monopole antenna of the same size. During this time the signal transmitted from, and received on, the plasma antenna also remained approximately constant in amplitude (fluctuations about + or - 1 dB). This useful lifetime of the plasma antenna was varied from about 200 microsecs to about > 2000 microsecs by changing the duration of the electric discharge sustaining the plasma columns. In these experiments, the noise from the plasma antenna was not distinguishable from that developed using a copper antenna, but in both cases the noise was much larger than the true thermal noise background.
- Publication:
-
Naval Research Lab. Report
- Pub Date:
- May 1982
- Bibcode:
- 1982nrl..reptX....G
- Keywords:
-
- Electric Discharges;
- Laser Applications;
- Monopole Antennas;
- Plasmas (Physics);
- Radio Antennas;
- Background Noise;
- Plasma Conductivity;
- Radio Reception;
- Radio Transmission;
- Communications and Radar