Synthesis of Radiometric Receivers on the Criterion of Statistical Invariance to Fluctuations of Strengthening and Narrow-band Interference

Abstract

The tasks of practical veterinary medicine related to the development of new methods and tools for the operative diagnosis of inflammatory diseases and traumas of agricultural and domestic animals require the development of fundamentally new methods and equipment for noninvasive diagnosis of the condition of animals.For remote measurement of their own thermal electromagnetic radiation of animals, the radiometric receiver was synthesized behind the criterion of statistical invariance to the AC fluctuations and to the effect of narrow-band interference.The scheme of a synthesized radio receiver is substantiated, which is invariant with respect to the AC fluctuations and completely invariant with respect to a narrow-band harmonic type. The peculiarity of this scheme is that in this radio receiver the input signal coming from the antenna in the input circuit is divided by power into two components, one of which is delayed by the time τ, and then these components are added together in the adder. Then there is amplification followed by division into two components, one of which is delayed for the same time τ, and then these components are multiplied, and their product is averaged.In accordance with the obtained expressions, for the impulse response of the input circuit and the quadratic detection scheme, the structure of the synthesized radio measuring receiver is constructed. For practical purposes, a radio measuring receiver with parameters is made: sensitivity – 10-17 W; frequency range – 30–40 GHz; measuring speed – 0.5 s; measurement accuracy – 0.1–0.2 ºC.Practical testing of the radiometric receiver shows the possibility of displaying the temperature of internal tissues, obtaining a visual picture of the heat field, which allows the veterinarian to establish the correct diagnosis