FLEXIBLE PROTECTING SCREENS FOR MICROWAVE BAND ON THE BASIS OF THIN CONDUCTING FIBERS

Abstract

The availability of radio communication, television, radiolocation, remote information processing systems led to the appearance of an intense electromagnetic background in our environment. In many cases, it is the cause of the disturbance of the correct functioning of biological objects, a hindrance to the operation of radioelectronic devices – information transmission systems and military equipment. Therefore, there is a need to protect objects from electromagnetic radiation. Particular attention is given to the development of screens and coatings, the effectiveness of which is achieved through the absorption of electromagnetic radiation, since the reflection of electromagnetic radiation often has a negative effect associated with the formation of a re-reflected wave effecting the screened object. In addition, it can help to identify an object by external sensors in cases where it is undesirable. The effect of an anomalously large absorption of microwave radiation by conducting fibers is observed when electric vector of an electromagnetic wave which falls on a fiber is parallel to the axis of the fiber. The possibility of using this effect to create protective screens is considered in this paper. The study showed that electromagnetic radiation is very strongly absorbed and dissipated by thin conducting fibers if the electric vector of the wave is parallel to the fiber axis: the values of the absorption and scattering efficiency factors can reach several hundred and even thousand, that is, the effective absorption and scattering cross sections can be in several hundred or thousand times higher than the geometric cross sections of the fiber. This is a size effect, the nature of which, perhaps, is related to the effective excitation of currents at certain ratios between the fiber diameter and the wavelength of the radiation. Also in the work, the advantages of graphite fibers in front of metal ones as a material for absorbing screens have been experimentally proved. The results of the study can be used to create protective screens in the microwave range.

Keywords

• absorption
• microwave radiation
• protective screen
• thin fiber