Study on the gain of plasma antenna

This paper presents the results of study on the gain of plasma antenna. The plasma antenna is an annular fluorescent lamp driven either by 220 V AC source or by a RF signal source. A metallic antenna with same dimension is used as a reference. The far field strengths and VSWRs of these three antennas are measured. The gains of the plasma antennas relative to that of the reference metallic antenna were calculated. Results show that the average gains of these two plasma antennas are much lower (6 dB lower for AC driven, 6.7 dB lower for RF driven) than the metallic counterpart and the gain differences are much larger at high-end band than those at low-end band. NEC2 package is used to calculate the antenna factor of the receiving antenna and thereafter the absolute gains of the individual antennas are evaluated.