Complimentary split ring resonator sensor with high sensitivity based on material characterization

Through the investigation of previous characterization techniques, determination accuracy of the real permittivity of MUT depends on frequency shift value of the sensor resonant frequency due to loading sample, and this frequency shift value which is provided by planar sensors based on CSRR Is confined and restricted according to the design criteria of the planer sensors such as the relative permittivity of sensors substrate in addition to the physical dimensions of CSRR. [...]the precision of calculation is limited by this value. [...]a structure with low effective permittivity of substrate is achieved, where it is founded later after careful verification that this technique improves the precise of materials characterization employing the planer sensors based CSRR. The suggested sensor is simulated on a FR4 substrate and is point to be active in the range of frequency 1.74 to 3.4 GHz. 2.THEORY For traditional microwave resonator established method, the overall expressions narrative the variation in resonant frequency for permeability and permittivity of the specimen under test are given as shown in (1) [24]: ... where, vc is the cavity volumes, Afr represent the change in resonant frequency, Ae and Aß are the change in complex permittivity and complex permeability, respectively, add to that eø is the free space permittivity, while ß0 perform permeability of the free space. For this purpose, in this work, two CSRR unit cells, with and without hole are compared for the sensibility test employing the HFSS. 3.DESIGN AND ANALYSIS OF THE STRUCTURE The proposed structure is one type of the quasi-static consist of substrate with hole and split rings in two ports in which an inductance stimulated by circulating current in the rings and the effective capacitance increased across the space through the rings, hence electrically small resonator is achieved.