The measurements of complex dielectric permittivity (CDP) ε{sup}*=ε'-jε" for liquid systems with great (ε"/ε'≥1), medium, and small losses (ε"/ε'<5×10{sup}-2) in microwave diapason are carried out by wave-guide and resonance methods. The method of closing and idle method as well as method of liquid layer variation and balance methods are mostly used. All these methods allow to determine ε and ε" with high precision for liquids with medium losses. For liquids with values ε"/ε'>1 the precision of exciting methods abruptly decreases. The errors of CDP measurements in highly absorbed substances caused by the principles of ε'(2...3%) and ε"(4...10%) measuring in these methods. For instance, the determination of ε' and ε" in wave-guide methods uses the curve of distribution of electric field in liquid. By measuring the wavelength in liquid and the depth of successive maxims of the field they determine phase constant β = 2π/λ{sub}(liq) and absorption constant α = lg(P{sub}1 -P{sub}2)/λ{sub}(liq). However, the curve of electric field distribution in liquids with high absorption is very flat in the vicinity of extremes and this fact lead to the growth of errors of wavelength measuring and constants α and β determination. The existing resonator methods of investigation of the liquids with high absorption dealt with the usage of wave-guide units that need preliminary calibration.
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