Control of parameters of dielectric antenna coverings according to the reflection coefficient frequency dependence by quasi-solution search method

Abstract

Manufacturing dielectric layers for antenna coverings in a strict agreement with the designed ones and stability of their parameters under exploitation is a necessary condition of antenna system effective functioning. It dictates a necessity of layer parameter control both in a technological manufacturing process and in practical using. For operative control it is desirable to use non-destructive remote one-side testing based on the reflection coefficient frequency dependence measurement. In this case it is recommended to conduct the measurements in MM and short CM range of wavelength by multifrequency methods to guarantee a high precision and a possibility of considering the covering as locally flat one. Under conditions of additional measurement errors of both random and determined character (the latter being caused by the inadequacy of mathematical model to the concrete physical situation of the measurements), this task should be solved by the method of quasi-solution search, as only in this case it is possible to obtain stable results. As a practical application of this method for processing the data of the measurements of a realistic dielectric structure by MCS RIMCH-01-04 has shown, it is enough to use a sum of complex coefficients as a model of the reflection from the layered structure. The coefficients are defined by the values of the reflection from the indicated interfaces of the layered structure. Other reflections from the antenna construction elements have been effectively removed by the time-gating. Presence of a high-level noise calls for a special method of regularization for the quasi-solution search. After testing on the realistic constructions the Rayleigh criterion has been exceeded in two times.