X-band metamaterial absorbing sensor

The invention relates to an X-band metamaterial absorbing sensor including three layers from bottom to top. A metal bottom plate and a bottom substrate are formed at the first layer; a micro flow channel layer is formed at the second layer; and a top substrate and a resonator are formed at the third layer. The three layers are bonded into one to form an absorbing resonance unit. The resonator is formed on the top substrate and has an inner-outer double ring structure. The half upper part of the micro flow channel layer is etched to form a double-ring groove so as to form a micro flow channel,wherein the micro flow channel is distributed in a strong electric field resonance region facing the resonator. Tested liquid is injected into the senor and thus the dielectric constant of the micro flow channel region changes to cause the shift of the absorption frequency point, wherein the shift degree can be used as a characterization parameter for different tested liquids. When the relative dielectric constant of the