Plasma Antenna
A radiofrequency antenna that uses ionized plasma gas instead of solid metal conductors to transmit and receive electromagnetic signals.
Governing formula
Conductivity σ_p = (n_e e²) / (m_e (ν_coll - i ω))
SI unit
MHz / GHz (RF Operating Frequency)
In depth
When energized, gas ionizes into a conductor capable of transmitting RF signals. De-energizing the plasma turns the antenna off instantly, reducing radar cross-section and eliminating co-channel interference.
Examples in the real world
Reconfigurable stealth military antennas that vanish when unpowered to prevent radar detection.