A Two-Port Microstrip Sensor Antenna for Permittivity and Loss Tangent Measurements

摘要

A two-port microstrip sensor antenna system is presented for characterizing different materials. The proposed sensor antenna can estimate both permittivity and loss tangent of a sample under test (SUT). Compared to the single port sensor antenna, the proposed sensor antenna system is more practical since the working frequency of the system can be adjusted easily. The permittivity of material has a huge impact on the antenna resonance, while its loss tangent affects power transmitted to the second port. Therefore, by finding out the antenna resonance and the level of transmission response, one can characterize the materials. The results show that the antenna radiation pattern is not deteriorated for samples with different permittivities and loss tangents.