The Algorithm Research On Microwave Dielectric Spectra Information Acquisition

The application of microwave dielectric spectrum can be used to design a sensor of security in food, biological and medical industry. Through Cole-Cole、Davidson–Cole and Havriliak-Negami model we can calculate four related parameters dependent on the qualities of samples. When we choose Evolutionary Algorithm(genetic algorithm and Particle swarm optimization method) and Marquardt algorithm, Davidson–Cole model’s results on single fitting the imaginary part of complex dielectric constant are better than others(its static dielectric constant is 78 ?1,Chi square coefficient is 5 ?1.5, mean square deviation is lower than 0.85), but in Cole-Cole double fitting the result is better when we use Marquardt algorithm(its static dielectric constant is 78 ?1,Chi square coefficient is lower than 5, mean square deviation is lower than 0.74). And in this paper taking dimethyl sulfoxide(DMSO) as an example I calculate the static dielectric constant of aqueous DMSO solution and the conductivity of aqueous DMSO-sodium chloride solution under external electric fields by Molecular Dynamic Simulation. The simulation that is used frog-leaping algorithm, Parrinello-Rahman coupling pressure and Nose-Hoover coupling temperature has achieved the convergence of static dielectric constants and reasonable conductivities of solutions. In addition, in food security molecular differentiating can be used to sense the concentration of solutions, we suggest an empirical equation from the fitting of microwave dielectric spectrum of Monosodium glutamate solution and the empirical equation can monitor both the temperature and concentration of solutions in real time.To summarize, the application of microwave dielectric spectrum has many advantages in molecular differentiating. It can provide fundamental scheme and data for real time monitoring using the fitting of microwave dielectric spectrum and Molecular Dynamic Simulation. Then the technology of microwave dielectric spectrum can be matched with the carried sensor in smart mobile phone, which has a huge social value and a good marketing prospect.