Article 5120

Title of the article

THE IMPACT OF REFLECTIONS FROM TREES’ TRUNKS ON SIGNAL FORMATION OF RADIO-WAVE DEVICES OF METER RANGE DETECTION IN THE WOODS 

Authors

Tokarev Nikolaj Nikolaevich, Candidate of engineering sciences, chief specialist for radar facilities, division No.134, Research and Design Institute of Radioelectronic Equipment – branch of Production Enterprise “Start” named after M. V. Protsenko (building 1, 1, Mira avenue, Zarechny, Penza region, Russia), E-mail: office@nikiret.ru 

Index UDK

621.396 

DOI

10.21685/2072-3059-2020-1-5 

Abstract

Background. In the procedure of security of state facilities, the urgent task is to detect intruders in the wood. The advanced means of solving this problem is buried radio-wave detectors operating within VHF band. The aim of this work is to study the effect of side reflections at tree trunks on the signal formation in radio-wave detectors to assess the likely distortion of the intruder signals in the wood.
Materials and methods. The article describes previously developed signal generation models of radio-wave detectors based on the well-known assumptions for the specified frequency range, ground parameters and distances.
Results. Reflections of electromagnetic waves from tree trunks cause a change in the intruder’s signal in the wood compared with the signal generated by an intruder in the open space. Simulation of these processes shows that: the change in signal amplitude generated by the intruder in the wood is caused by the relative position of the tree trunks relative to each other and relative to the Fresnel zones of radio-wave detectors; maximum effect on the amplitude of the intruder signal is caused by trees located within the first Fresnel zone; the amplitude change of the intruder signal is maximum when the intruder moves near the tree trunk and can reach 10–20 % of its amplitude in open space; the signal amplitude of the intruder in the wood changes more when the ground is wet, but it is within its value when the ground is dry.
Conclusions. When radio-wave detectors are located in the wood, one should consider that signal amplitude generated by an intruder can be reduced. The simplest way to compensate for its reduction is to reduce the distance between the transmitter and receiver of the radio-wave detectors. 

Key words

scattered field of tree trunk, intruder scattering field, direct signal,  intruder signal 

Download PDF
References

1. Sredstvo obnaruzheniya dvukhpozitsionnoe radiovolnovoe podzemnoe «BSK-RVP». Pasport BAZhK.425142.058 PS [Underground two-way radio wave detector “BSK-RVP”. Passport BAZhK.425142.058 PS]. Available at: http://nikiret.ru/upload/iblock/
85b/BSK_RVP.-Pasport-v18.pdf. [In Russian]
2. Sredstvo obnaruzheniya mnogozonal'noe radiovolnovoe podzemnoe «Raps-M2». Rukovodstvo po ekspluatatsii. BAZhK.425142.069 RE [Detection tool multizonal radio wave underground “Raps-M2”. Manual. BAZhK.425142.069 RE]. Available at:
http://nikiret.ru/upload/iblock/154/RAPS_M2.-Rukovodstvo-po-ekspluatatsii-v-11.pdf. [In Russian]
3. Tokarev N. N. Izvestiya vysshikh uchebnykh zavedeniy. Povolzhskiy region. Tekhnicheskie nauki [University proceedings. Volga region. Engineering sciences]. 2019, no. 2 (50), pp. 69–87. [In Russian]
4. Lavrov G. A., Knyazev A. S. Prizemnye i podzemnye antenny [Ground and underground antennas]. Moscow: Sov radio, 1965, 472 p. [In Russian]
5. Olenin Yu. A., Tokarev N. N. Novye promyshlennye tekhnologii [New industrial technologies]. 1999, no. 4–5 (291–292), pp. 49–61. [In Russian]
6. Tokarev N. N. Radiotekhnika [Radio engineering]. 2013, no. 2, pp. 98–102. [In Russian]
7. Vens E. F. Vliyanie elektromagnitnykh poley na ekranirovannye kabeli: per. s angl. [The impact of electromagnetic fields on shielded cables: translated from English]. Moscow: Radio i svyaz', 1982, 120 p. [In Russian]
8. Tokarev N. N. Problemy ob"ektovoy okhrany: sb. nauch. tr. [Object security issues]. Issue 1. Penza: Izd-vo PGU, 2000, pp. 93–108. [In Russian]

 

Дата создания: 15.05.2020 09:20
Дата обновления: 15.05.2020 10:27