As the use of shielded rooms becomes more and more extensive, some problems in the design of shielded rooms have attracted more and more attention. The following are some matters needing attention in the design of wave absorbing materials in shielded rooms.
1. Bandwidth design
The bandwidth design is determined by the wave-permeable material. The wave-permeable material constructs the base of the wave-absorbing material. The wave-permeable material is responsible for the transmission of electromagnetic waves in the wave-absorbing body. In the future, expanding the absorption bandwidth should maintain the continuity of the wave-absorbing body matrix. In addition to the gridding of transmission channels, the continuity and penetration of wave-transmitting materials are extremely beneficial to expand the absorption frequency of electromagnetic waves. The cross-sectional dimension perpendicular to the incident electromagnetic wave and the development of the internal transmission channel are not only extremely beneficial to expanding the bandwidth, but also creating a prerequisite for the improvement of the absorption efficiency. Therefore, the role of expanding the bandwidth should be given priority in the design of the absorber.
2. Design of absorption efficiency
The absorber is responsible for the task of absorbing electromagnetic waves. The shape (particles, fibers, flakes) and distribution of the absorber have an important influence on the absorption efficiency. Conductive materials distributed evenly along the wave-transmitting channel can maximize the absorption efficiency. If the absorbing particles or fibers occupy or block the electromagnetic wave transmission channel, it will cause electromagnetic wave reflection, so that the electromagnetic wave cannot penetrate into the occupied place. Here and the subsequent wave absorber not only can not perform the function of absorbing electromagnetic waves, but instead It will increase the thickness of the absorber. If the conductive particles or fibers only reduce the effective cross-section of the electromagnetic wave transmission channel, the frequency range will be reduced, thus causing a decrease in the absorption efficiency.
3. Design in terms of shape or thickness
The structural design can achieve multiple reflections of electromagnetic waves and resonance to increase the absorption efficiency. The electromagnetic wave can also be introduced into the interlayer (CAH series pyramid) with a larger space by using wave-transmitting materials. A large number of absorbing materials installed inside the interlayer can Give full play to the absorption function.
Noted the design of the wave absorbing material, the organic combination of the wave-transmitting material and the absorber is needed to solve the problems of impedance matching, absorption efficiency, and thickness of the absorber, and better design and composition can achieve better shielding. room.