Safety Aspect Analysis of Helmet Mounted Millimeter Wave Radio

  • K. Nageswari Govt. Medical College, Chandigarh
  • Mr. Khemchandra Defence Institute of Physiology & Allied Science, Delhi
Keywords: Horn antennas, Microwave measuring probes, MMW, Millimetric wave power density

Abstract

Measurements of millimetric wave (MMW) power density from two-helmet-mounted MMW radiating horn antennas were made at various distances on the three axes. These three axes are representing three planes: (i) in the direction of propagation (Z-axis), (ii) horizontal axis perpendicular to the direction of propagation (Y-axis), i.e., 15 cm to the left or right of Z-axis, and (iii) vertical axis (X-axis) also perpendicular to the direction of propagation and extending up and down an imaginary central reference line passing through the centre of the horn and the centre of the microwave measuring probe. Measurements were also made inside the helmet close to the metallic plate at 17 locations and 10 cm away from it. The Narda-8723 broadband isotropic microwave probe [frequency of operation (0.3-40 GHz) power density range 0.05-100 mW/cm1 was placed at various distance points marked at 15 nm intervals and also at distances of relevance on Z-axis. For each of the distance points on Z-axis, measurements were taken at 7 probe locations on X-axis. For Y-axis measurements, 4 probe locations were selected (on vertical or X-axis). The results revealed no leakage of microwave power inside the helmets. In the transmitting mode of operation, there was a great variability of microwave power emitted closest to the horn antennas (2.5-5.0 mW / 2 and 6.0-105 mW /cm2 for helmet Nos.11 and2, respectively). As the distance from the antenna increased in the direction of propagation, the power density dropped to 0.04 m W / cm2 or 0.075 m W / cm{ maximum value at 1 m. As the values recorded are within American National Standards Institute (ANSI safety guidelines (10mW/cm2) at 35 GHz.

Author Biographies

K. Nageswari, Govt. Medical College, Chandigarh
Govt. Medical College, Chandigarh
Mr. Khemchandra, Defence Institute of Physiology & Allied Science, Delhi
Defence Institute of Physiology & Allied Science ,Delhi.

References

Khizhnyak, E.P. & Marvin, C.Z. Heating patterns in biological tissue phantoms caused by millimeter wave electromagnetic irradiation. IEEE Trans. Biomed. Engg., 1994, 41(9), 865-73.

Betsky, O.V.; Petrov, I.Yu.; Tyazhelov, V.V.; Khizhnyak, E.P. & Yaremenko, Yu.G. The distribution of electromagnetic fields of the millimeter wave length range in phantoms and biological tissues on the near-field area of the irradiators. Doklady Akademii Nauk SSSR, 1989,309,230-33.

Balantsev, V. N.; Lebedev, A.M.; Sevastjariov,V.A. & Kumetsov, A.N. Numerical investigations of SAR distribution in two-dimensional models of horn antennas with biological objects. International Symposium on Millimeter Waves of Non-them1 Intensity in Medicine (Digest), 3-6 October 1991 Moscow, USSR. pp. 660-64.

Li, Jian & Guo, Yai. Changes of mouse blastomeres by millimeter microwave irradiation. Proceedings of the International Symposium on Electromagnetic Compatibility, September 1989, Nagoya, Japan. pp. 521-27.

Guo, Yao; Su, De-Zheng; Li-Xi & Zhu, Peng-Jiu. The indirect bioeffects of millimeter microwave. Proceedings of the International Symposium on Electromagnetic Compatibility, September 1989, Nagoya, Japan. pp. 519-20.

Maria, A. Stuchly. Health effects of exposure to electromagnetic fields. IEEE, 1995,O - 7803 - 2473 - 0195. 18 p.

Published
2013-01-01
How to Cite
NageswariK., & KhemchandraM. (2013). Safety Aspect Analysis of Helmet Mounted Millimeter Wave Radio. Defence Science Journal, 49(3), 217-227. https://doi.org/10.14429/dsj.49.3832
Section
Biomedical Sciences