大功率无线电波与低电离层的相互作用

地面入射的大功率无线电波能加热电离层等离子体，引起电离层电子温度和密度的扰动，实现电离层的地面人工变态．本文中，着重考虑电波和电离层相互作用过程中的自吸收，构造一个自治的相互作用模型，在一定功率和频率的加热电波作用下，利用该模型计算了白天低电离层电子温度和由温度的变化而引起的电子密度的变化．计算结果表明，在白天低电离层，电波的自吸收在90km以下比较显著，而最大温度变化在70km高度上，大约增加了2倍．在α复合的假设下，电子密度变化幅度随高度的增加而减少，在70km处，大约增加55％、120km处则为4％左右．

INTERACTION BETWEEN THE POWERFUL HIGH-FREQUENCY RADIO WAVE AND THE LOWER TERRESTRIAL IONOSPHERE

The terrestrial ionospheric plasma can be heated by a powerful ground-based high-frequency radio wave, which results in the disturbance of the electron temperature and density. In this paper, a self-consistent model of interaction between the powerful HF radio wave and the lower ionosphere is presented. In this model, the self-absorption effect of radio wave is emphasized. For specific transmitter's parameters (in this paper, PER = 200MW, f= 7.0MHz are used, which is at the range of many transmitters), under the daytime ionospheric background, the calculated results show that the self-absorption effect is obvious, when h < 90 km, but the effect can be ignored for h > 90 km. The results also show that the maximum electron temperature enhancement is at the altitude of 70 km, which is three times of the undisturbed background. With the assumption of a recombination in lower ionosphere, the percentage of electron density enhancement is decreasing with the increase of ionospheric heights. For example, at the altitude of 70km, it is 55% or so, but at 120km altitude, it is about 4%.