Development of Porous TiO_2 W-band Wave Absorber

摘要

This paper introduces porous titania, TiO_2, as a radio absorbing material, and presents the results of measurements of the complex permittivity and reflection power characteristics of single-layered absorber backed by metal plate at W-band. Porous titania is a lossy dielectric material, and absorbers made of it is durable, non-inflammable, thin and light weight. These features conform to architecture and interior design and safety measures, so that the installation in broader places for radio clean environment will be expected. In the paper, first, the manufacturing process of porous titania and its physical characteristics are presented. Second, the complex permittivity measured at W-band by free-space transmission method is presented. Third, based on this value, a single-layered absorber based by metal plate is designed, and its reflection power characteristics measured at normal incidence and at 80-105GHz are presented. The derived permittivity is compared to the result by the free-space transmission method. Finally, another method of the reflection power characteristics, electric field vector rotation method, is presented. Both results show good agreement.