A thermionic plasma source apparatus has been developed and characterised for high-density gaseous plasma antenna (GPA) applications. The system produces a cylindrical plasma column which is 100 mm long with a diameter of 8 mm and operates with a total plasma power consumption of 70 to 200 W, depending mainly on the DC discharge current. The plasma column electron density and temperature is measured via microwave interferometry and optical emission spectroscopy. The plasma properties are investigated for Ar, Kr and Xe at pressures from 1 to 4 mbar. The system has demonstrated higher electron densities (>10¹⁹ m⁻³) at low pressures (<2 mbar) than has been experimentally achieved before for GPA applications. This could allow for high gain GPA operation comparable to that of conventional metallic antennas. Additionally, the source has demonstrated operation over a wide range of electron densities, from 2 10¹⁸ to 1 10¹⁹ m⁻³, which can allow for frequency hopping. The plasma columns electron temperature remains around 1.5 eV for argon, largely uninfluenced by the pressure or discharge current. These plasma column measurements obtained are used to analyse the plasma properties influence on GPA performance. This analysis indicates that at high density operation, a gain is achieved which is only 22% lower than that of the conventional metallic antenna. Furthermore, the density ranges demonstrated could enable wide-range frequency hopping of over 100 MHz, with a gain greater than 1.3 dBi.

已经开发了热电子等离子体源设备，并对其特征进行了描述，以用于高密度气态等离子体天线（GPA）应用。该系统生产的圆柱形等离子柱长100 mm，直径8 mm，其总等离子功率消耗为70至200 W，这主要取决于直流放电电流。等离子体柱电子密度和温度通过微波干涉法和光发射光谱法测量。在1至4 mbar的压力下研究了Ar，Kr和Xe的等离子体性能。该系统显示出更高的电子密度（> 10 ¹⁹  m ^-3）（低于2毫巴）在低压下（小于GPA应用之前的实验）。这可以允许与常规金属天线相比的高增益GPA操作。此外，该离子源已证明可在2 10 ¹⁸至1 10 ¹⁹  m ^-3的广泛电子密度范围内工作，这可以允许跳频。氩气的等离子柱电子温度保持在1.5 eV左右，在很大程度上不受压力或放电电流的影响。获得的这些血浆柱测量值用于分析血浆性质对GPA性能的影响。该分析表明，在高密度操作下，获得的增益仅比常规金属天线低22％。此外，所展示的密度范围可以实现超过100 MHz的宽范围跳频，增益大于1.3 dBi。