Evaluation of E-Field Distribution and Human Exposure for a LTE Femtocell in an Office
关键词:
Electric field, femtocell, LTE, RF exposure, SAR摘要
Firstly, the finite-difference time-domain (FDTD) method was used to calculate electric fields emitted from a long-term evolution (LTE) femtocell placed at the left-hand side of an empty office at frequencies of 700, 860, 1990, and 2600 MHz. After validating the accuracy of the FDTD method, the FDTD method was used to calculate electric field distributions inside the office, with and without the presence of 20 people and furniture for the LTE femtocell placed near the center of a horizontal plane with a distance of 1.0 m from the ceiling and transmitting a power of 10 dBm. Simulated electric fields at most of the locations on the horizontal plane with a height of 1.0 m above the floor for the office with and without the presence of 20 people and furniture are found in the range of -10 to -30 dBV/m, which means a good signal will be picked up in the office. The maximum power density emitted from the LTE inside the office and maximum localized SAR induced in a standing person are far below the ANSI/IEEE safety standard for public exposure in uncontrolled environments.
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参考
LTE-Advanced: The 3rd Generation Partnership Projected, 2011 [Online]. Available: http://www. 3gpp.org/LTE-Advanced
S. Sesia, I. Toufik, and M. Baker, LTE-The UMTS Long Term Evolution-From Theory to Practice, 2nd ed. including Release 10 for LTE-Advanced, New York: John Wiley & Sons, 2011.
F. Khan, LTE for 4G Mobile Broadband-Air Interface Technologies and Performance, Cambridge University Press, New York, 2009.
G. M. Whitman, K.-S. Kim, and E. Niver, “A theoretical model for radio signal attenuation inside buildings,” IEEE Trans. Veh. Technol., vol. 44, no. 3, pp. 621-629, 1995.
R. P. Torres, L. Valle, M. Domingo, and M. C. Diez, “CINDOOR: An engineering tool for planning and design of wireless systems in enclosed spaces,” IEEE Antennas Propagat. Mag., vol. 41, no. 4, pp. 11-22, 1999.
Z. Ji, B. H. Li, H. X. Wang, H. Y. Chen, and T. K. Sarkar, “Efficient ray-tracing methods for propagation prediction for indoor wireless communications,” IEEE Antennas Propagat. Mag., vol. 43, no. 2, pp. 41-49, 2001.
A. Aragon-Zavala, B. Belloul, V. Nikolopoulos, and S. R. Saunders, “Accuracy evaluation analysis for indoor measurement-based radio-wavepropagation predictions,” IEE Proc.-Microw. Antennas Propag., vol. 153, no. 1, Feb. 2006.
X. Ling and K. L. Yeung, “Joint access point placement and channel assignment for 802.11 wireless LANs,” IEEE Trans. Wireless Commun., vol. 5, no. 10, pp. 2705-2711, Oct. 2006.
D. Plets, W. Joseph, K. Vanhecke, E. Tanghe, and L. Martens, “Simple indoor path loss prediction algorithm and validation in living lab setting,” Wireless Pers. Commun., vol. 68, pp. 535-552, 2013.
V. Degli-Esposti, G. Falciasecca, F. Fuschini, and E. M. Vitucci, “A meaningful indoor path-loss formula,” IEEE Antennas Wireless Propag. Lett., vol. 12, pp. 872- 875, 2013.
M. Ayadi and A. Ben Zineb, “Body shadowing and furniture effects for accuracy improvement of indoor wave propagation model,” IEEE Trans. Wireless Commun., vol. 13, no. 11, pp. 5999-6006, Nov. 2014.
NCRP, “Biological effects and exposure criteria for radiofrequency electromagnetic fields,” NCRP Rep. 86, 1986.
IEEE Standard for Safety Levels with Respect to Human Exposure to Radio Frequency Electromagnetic Fields, 3 kHz to 300 GHz, IEEE Standard C95.1, 2005.
ICNIRP, “Guidelines for limiting exposure to timevarying electric, magnetic and electromagnetic fields,” Health Phys., vol. 74, no. 4, pp. 494-522, Apr. 1998.
P. Frei, E. Mohler, G. Neubauer, G. Theis, A. Burgi, J. Frohlich, C. Braun-Fahrlander, J. Bolte, M. Egger, and M. Roösli, “Temporal and spatial variability of personal exposure to radiofrequency electromagnetic fields,” Environ. Res., vol. 109, pp. 779-785, 2009.
H. Y. Chen and C. Y. Chuang, “Currents induced in human bodies during RF exposure near a cellular phone base station,” Electromagn., vol. 29, no. 1, pp. 13-23, Jan. 2009.
W. Joseph, P. Frei, M. Ro¨osli, G. Vermeeren, J. Bolte, G. Thur´oczy, P. Gajsek, T. Trcek, E. Mohler, P. Juhasz, V. Finta, and L. Martens, “Betweencountry comparison of whole-body SAR from personal exposure data in urban areas,” Bioelectromagn., vol. 33, no. 8, pp. 682-694, Dec. 2012.
J. Cooper, B. Marx, J. Buhl, and V. Hombach, “Determination of safety distance limits for a human near a cellular base station antenna, adopting the IEEE standard or ICNIRP guidelines,” Bioelectromagn., vol. 23, no. 6, pp. 429-443, 2002.
T. Alanko, M. Hietanen, and P. von Nandelstadh, “Occupational exposure to RF fields from base station antennas on rooftops,” Ann. Telecommun., vol. 63, pp. 125-132, 2008.
D. Plets, W. Joseph, K. Vanhecke, and L. Martens, “Exposure optimization in indoor wireless networks by heuristic network planning,” Progress Electromagn. Res., vol. 139, pp. 445-478, 2013.
G. Koutitas and T. Samaras, “Exposure minimization in indoor wireless networks,” IEEE Antennas Wireless Propag. Lett., vol. 9, pp. 199-202, 2010.
A. Bamba, W. Joseph, J. B. Andersen, E. Tanghe, G. Vermeeren, D. Plets, J. O. Nielsen, and L. Martens, “Experimental assessment of specific absorption rate using room electromagnetics,” IEEE Trans. Electromagn. Compat., vol. 54, no. 4, pp. 747-757, Aug. 2012.
A. Boursianis, P. Vanias, and T. Samaras, “Measurements for assessing the exposure from 3G femtocells,” Radiation Protection Dosimetry, vol. 150, no. 2, pp. 158-167, 2012.
A. Bamba, W. Joseph, A. Boursianis, T. Samaras, G. Vermeeren, A. Thielens, and L. Martens, “Fast assessment of RF power absorption in indoor environments by room electromagnetics theory,” Radiation Protection Dosimetry, first published online Nov. 14, 2015.
K. S. Yee, “Numerical solution of initial boundary value problems involving Maxwell’s equations in isotropic media,” IEEE Trans. Antennas Propag., vol. AP-14, no. 5, pp. 302-307, 1966.
Narda Safety Test Solutions, 435 Moreland Road, Hauppauge, NY 11788, 2015.
G. Mur, “Absorbing boundary conditions for the finite-difference approximation of the time-domain electromagnetic field equation,” IEEE Trans. Electromagn. Compat., EMC-23, pp. 377-382, 1981.
Z. P. Liao, H. L. Wong, B. P. Yang, and Y. F. Yuan, “A transmitting boundary for transient wave analysis,” Scientia Sinica (Series A), vol. 27, no. 10, pp. 1063-1076, Oct. 1984.
J. P. Berenger, “A perfectly matched layer for the absorption of electromagnetic waves,” J. Comp. Phys., vol. 114, pp. 185-200, Oct. 1994
A. von Hippel, Dielectric Materials and Applications, The MIT Press, Cambridge, Mass., 1954.
C. F. Yang, C. J. Ko, and B. C. Wu, “A free space approach for extracting the equivalent dielectric constants of the walls in buildings,” IEEE AP-S. Int. Symp. Dig., Baltimore, MD, vol. 2, pp. 1036-1039, July 21-26, 1996.
D. J. Cichon, T. Zwick, and J. Lahteenmaki, “Ray optical indoor modeling in multi-floored buildings: simulations and measurements,” In AP-S. Digest, Antennas and Propagation Society Int. Symp., Newport Beach, CA, vol. 1, pp. 522-525, July 21- 26, 1995.
A. C. M. Austin, M. J. Neve, and G. B. Rowe, “Modeling propagation in multifloor building using the FDTD method,” IEEE Trans. Antennas Propag., vol. 59, no. 11, pp. 4239-4246, Nov. 2011.
M. Thiel and K. Sarabandi, “3D-wave propagation analysis of indoor wireless channels utilizing hybrid methods,” IEEE Trans. Antennas Propag., vol. 57, no. 5, pp. 1539-1546, Nov. 2019.
D. Pena, R. Feick, H. D. Hristov, and W. Grote, “Measurement and modeling of propagation losses in brick and concrete walls for 900-MHz band,” IEEE Trans. Antennas Propag., vol. 51, no. 1, pp. 31-39, Jan. 2003.
S. K. Patil, M. Y. Koledintseva, R. W. Schwartz, and W. Huebner, “Prediction of effective permittivity of diphasic dielectrics using an equivalent capacitance model,” J. Appl. Phys., vol. 104, pp. 074108-1-074108-11, 2008.
LessEMF.com, Radio Frequency & Microwave Meters, 2014 [Online]. Available: http://www. lessemf. com/rf.html
A. Christ, A. Klingenbock, T. Samaras, C. Goiceanu, and N. Kuster, “The dependence of electromagnetic far-field absorption on body tissue composition in the frequency range from 300 MHz to 6 GHz,” IEEE Trans. Microw. Theory Tech., vol. 54, no. 5, pp. 2188-2195, May 2006.
J. A. Elder and D. F. Cahill, “Biological Effects of Radiofrequency Radiation,” U.S. Environmental Protection Agency, EPA Rep. no. EPA-600/8-83- 026F, Research Triangle Park, NC. 1984.
