| 摘要 |
<p>Apparatus for measuring the complex permittivity and conductivity, or a change in the complex permittivity and conductivity, of a dielectric material, comprises: a structure (1) which can be made to resonate at a radio or microwave frequency when in contact with or adjacent a dielectric material; first means (4), for providing a first indication, related to a change in resonant frequency of said structure when the latter is in contact with or adjacent said material as compared with a reference resonant frequency when not in contact with or adjacent said material; and second means (5, 6, 7, 8), for providing a second indication, related to the return loss when said structure is in contact with or adjacent said material, whereby the complex permittivity and conductivity, or a change in the complex permittivity and conductivity of said material can be calculated using said first and second indications.</p> |
