Pulsed energy storage antennas for ionospheric modification

Interesting, “new”, very high peak-power pulsed radio frequency (RF) antennas have been assembled at the HIPAS Observatory (Alaska, USA) and also at the University of California at Los Angeles (UCLA, USA); namely, a pair of quarter wavelength (λ/4) long cylindrical conductors separated by a high voltage spark gap. Such a combination can radiate multi-megawatt RF pulses whenever the spark gap fires. The antenna at HIPAS is 53 m long (λ/2) with a central pressurized SF6 spark gap. It is mounted 5 meters (λ/21) above a ground plane. It radiates at 2.85 MHz. The two antenna halves are charged to± high voltages by a Tesla coil. Spark gap voltages of 0.4 MV (at the instant of spark gap closure) give peak RF currents of ∼1200A which correspond to ∼ 14 MW peak total radiated power, or ∼56 MW of Effective Radiated Power (ERP). The RF pulse train is initially square, decaying exponentially in time with Qs of∼50. Two similar but smaller 80-MHz antennas were assembled at UCLA to demonstrate their synchronization with a pulsed laser which fired the spark gaps in the two antennas simultanoeously. These experiments show that one can anticipate a pulsed array of laser synchronized antennas having a coherent Effective Radiated Power (ERP)>10 GW. One can even reconsider a pulse array radiating at 1.43 MHz which corresponds to the electron gyrofrequency in the Earth’s magnetic field at ∼200 km altitude. These “new” pulsed high power antennas are hauntingly similar to the ones used originally by Hertz (1857–1894) during his (1886–1889) seminal verifications of Maxwell’s (1864) theory of electrodynamics.