研究了在300MHz以下频段,矩形巷道中存在电导率σ时电磁波传播的特性。研究表明,电磁波的传播具有很强的波导效应。巷道的截面越大,越有利于电波的传播。如果传播电波的频率低于截止频率,则衰减只和传播的频率有关。在截止频率以上,电导率越小,电磁波传播损耗越大;在相同的电导率下,随着频率的增加,衰减也将增加。TE波更适合于在巷道中传播。
This paper presents a study on the characteristics of electromagnetic wave propagation when specific conductance σ exists in rectangular cross section entries at the frequency band below 300MHz. Research results indicate that propagation of electromagnetic wave presents very strong wave guide effects. The larger the cross sectional areas of the entries, the better the propagation of electromagnetic waves will be. If the frequency of propagating electromagnetic waves is lower than blocking frequency, the attenuation is only related to the propagating frequency. While at the frequency above the blocking frequency, specific conductance is smaller, which increases losses in electromagnetic wave propagation. When the specific conductance remains unchanged, the attenuation increases with the increasing frequency.