Research On Error Analysis And Improved Methods Of Microwave Permittivity Measurement System

In recent years, microwave components have been widely used in wireless communication technology, remote sensing, aerospace and other high-tech fields, and material permittivity play a key role in it. However, with the change of temperature and frequency, permittivity of materials usually will change, it will eventually lead to the design parameters of microwave components change. Therefore, research on error analysis and improvement methods of the measured permittivity not only can effectively evaluate permittivity measurement result, still can give to improve the way of measurement results, guaranteed for the development of microwave components, electronic circuit and system.In this paper, the error analysis and improved methods of microwave permittivity measurement system have been the research objects in the broadband(1 ~ 39 GHz). First of all, this paper briefly introduces the common methods used for measuring permittivity of material in currently, and mainly analyzed principles of measuring permittivity of the transmission/reflection method and the open coaxial probe method, and it laid the theoretical foundation for the construction of permittivity measurement system.For the measurement of permittivity in broadband, this paper determined the scheme that transmission/reflection method and the open coaxial probe method are separately used to build permittivity measurement system, which the transmission/ reflection measurement system is divided into coaxial and waveguide transmission line measurement system; and in order to measure the permittivity of the powder materials in the transmission line measurement system, the PTFE spacer is used to hold the powder materials; based on these, the article separately analysis calibrations of measurement systems; by measuring the permittivity of the several common materials shows measurement systems is feasible and effective.In this paper, the error sources were separately determined according to the measuring principle of the transmission line measurement system and the opening coaxial probe measurement system, and in-depth analysis the error sources. In transmission line measurement system, the differential method is adopted in detail on the error of calculation formula according to the principle of measuring; in open coaxial probe measurement system, using the numerical method to calculate the error; thus the error analysis of the transmission line measurement system and open coaxial probe measurement system are comprehensively completed. The error sources of greater influence on the result of permittivity measurement are obtained by the simulation calculation of measurement error; Finally, for the error sources of the influence the result of the permittivity measurement, this paper respectively puts forward the way to reduce measurement error measurement results and to improve the measurement results.Through the above research, this paper well finished the measuring of microwave permittivity measuring system the in broadband the system and its error analysis and improvement. In addition, this paper adopts the calculating model of permittivity and of calculation program error analysis can be used in higher frequency measurement system, which laid a foundation for further study.