Theoretical analysis of the adaptive system for suppression of the interference concentrated on a spectrum
DOI:
https://doi.org/10.15587/2312-8372.2018.126356Keywords:
radiometric receiver, suppression of the spectrum-centered interference, compensating circuitsAbstract
The object of research is the process of interference suppression in a passive radiometric receiver, centered over the interference spectrum, with a random or varying frequency. Noise immunity can be increased by means of special circuits preventing the receiver from overloading and using differences in the characteristics of useful signals and interference to suppress the latter. As a rule, the frequency of noise oscillation is never accurately known and, in addition, the actual interference is never purely harmonic. Therefore, it became necessary to theoretically consider the degree of interference suppression by the input circuit of the radiometer at an unknown value of the interference frequency and the finite width of the spectrum, and also theoretically substantiate possible ways of constructing adaptive devices for suppressing real narrow-band noise.
An expression is obtained for the suppression coefficient of the interference concentrated on a spectrum, which shows that the interference will be suppressed automatically for the optimal choice of the parameters ka, τ, T of the servo system.
In the paper, a functional diagram of a radiometric receiver is presented, which uses an adaptive system to suppress the spectrum-centered interference. The adaptive system is based on the inclusion in the radiometric receiver circuit of additional compensating circuit interference. The interference compensating circuit makes it possible to increase the sensitivity of the receiver to 10-20 W with an accuracy of 0.1 ºC and a response rate of 2...4 s. In addition to interference suppression, the compensating link after the intermediate frequency amplifier is provided with interference suppression and an input circuit. In this case, the overall amplification in the noise immunity of the radiometric receiver in comparison with the compensating receiver, as calculations for typical characteristics show, will not be worse than 30 dB.
References
- Ioshenko, A. N. (2009). Noise interference of broadband communication systems with various methods of suppressing the spectrum-concentrated interference. Works of Educational Communication Institutes, 55, 19–30.
- Hutsol, T. (2017). Analysis of schematic variants of radiometric receivers. Bulletin of Kharkov Vasylenko National Technical University of Agriculture, 187, 107–109.
- Cherenkov, A. D., Kosulina, N. G. (2015). Theoretical Analysis of Electromagnetic Field Electric Tension Distribution in the Seeds of Cereals. Research Journal of Pharmaceutical, Biological and Chemical Scinces, 6 (6), 1686–1694.
- Hutsol, T. D., Cherenkov, A. D. (2017). Analysis of noise immunity and the electromagnetic environment in the areas of remote diagnostics of the state of animals with radiometric receiver. Bulletin of Kharkov Vasylenko National Technical University of Agriculture, 186, 144–146.
- Hutsol, T. (2017). Research on suppresion system analysis of high power narrowband interference operating in presence of heterodyne frequency. Scientific achievements in agricultural engineering, agronomy and veterinary medicine, 11 (1), 264–273.
- Poradish, F. J., Habbl, M. (2010). Millimeter wave radiometric imagingt ext. SPIE. Millimeter Wave Technology, 1, 337.
- Ring, E. F. J., Ammer, K. (2014). The technique of infrared imaging in medicine. Infrared Imaging. IOP Publishing, 1–10. doi:10.1088/978-0-7503-1143-4ch1
- DuBois, P. R., Williams, D. J. (1980). Increased incidence of retained placenta associated with heat stress in dairy cows. Theriogenology, 13 (2), 115–121. doi:10.1016/0093-691x(80)90120-x
- Skou, N. (1989). Microwave radiometer systems: Design and analysis. Boston-London: Artech House, 162.
- Jones, B. F. (1998). A reappraisal of the use of infrared thermal image analysis in medicine. IEEE Transactions on Medical Imaging, 17 (6), 1019–1027. doi:10.1109/42.746635
- Maldague, X. (2001). Theory and Practice of Infrared Technology for Nondestructive Testing. New York: Wiley, 704.
- Zheng, L., Tidrow, M. (2009). Analyses of infrared focal plane array figure of merit and its impact on sensor system trades. Infrared Physics & Technology, 52 (6), 408–411. doi:10.1016/j.infrared.2009.08.001
- Van Lamsweerde-Gallez, D., Meessen, A. (1975). The role of proteins in a dipole model for steady-state ionic transport through biological membranes. The Journal of Membrane Biology, 23 (1), 103–137. doi:10.1007/bf01870247
- Ash, C. J., Cook, J. R., Auner, C. R. (2009). The use of rectal temperature to monitor heat stroke. Missouri Medicine, 89 (5), 283–291.
- Togwa, T., Nemoto, T., Yamazaki, T., Kobayashi, T. (1976). A modified internal temperature measurement device. Medical & Biological Engineering, 14 (3), 361–364. doi:10.1007/bf02478138
Downloads
Published
How to Cite
Issue
Section
License
Copyright (c) 2018 Taras Hutsol
This work is licensed under a Creative Commons Attribution 4.0 International License.
The consolidation and conditions for the transfer of copyright (identification of authorship) is carried out in the License Agreement. In particular, the authors reserve the right to the authorship of their manuscript and transfer the first publication of this work to the journal under the terms of the Creative Commons CC BY license. At the same time, they have the right to conclude on their own additional agreements concerning the non-exclusive distribution of the work in the form in which it was published by this journal, but provided that the link to the first publication of the article in this journal is preserved.
