Experimental study on the surface wave driven plasma antenna

This experimental study examines the characteristics of a plasma antenna. For these experiments, we use a surface wave excitation at 450 MHz with RF power levels up to 40 W and gas pressure between 0.25 mb and 0.6 mb. Measurements of visible light from the plasma column confirm that the length of the antenna is linearly proportional to the square root of the excitation power and the proportionality factor is a function of gas pressure. Observations of the VSWR of the antenna show that decreasing the excitation power and increasing the pressure lead to the reduction of the resonant length of the antenna. The gain of the plasma antenna was measured between 110 and 300 MHz. The results show that the gain of a plasma antenna is considerably less than a conventional monopole antenna.