Helmet Antenna Design Using Characteristic Mode Analysis
关键词:
Characteristic mode analysis, folded dipole antenna, hemispherical shell, helmet antennas, omnidirectional pattern摘要
The helmet antenna is required to achieve hands-free operation for disaster prevention. The helmet antenna is not only low profile with a small configuration, but it also suppresses radiation toward the human head. This paper presents the characteristic mode analysis of the helmet, which is a hemispherical conductor shell to achieve the omnidirectional pattern in the horizontal plane. By deleting the weak part of the electric current on the hemispherical conductor shell, the shape of the folded dipole was obtained with a low resonant frequency. The folded dipole antenna with a slit-loaded copper ring structure with high radiation efficiency and a low SAR value was designed.
##plugins.generic.usageStats.downloads##
参考
H. King and J. Wong, “Effects of a human body on a dipole antenna at 450 and 900 MHz,” IEEE Trans. Antennas Propag., vol. 25, no. 3, pp. 376- 379, 1977.
H. R. Chuang, “Human operator coupling effects on radiation characteristics of a portable communication dipole antenna,” IEEE Trans. Antenna Propag., vol. 42, no. 4, pp. 556-560, Apr. 1994.
J. Lebaric and A. T. Tan, “Ultra-wideband conformal helmet antenna,” Asia-Pacific Microw. Conf., Sydney, Australia, pp. 1477-1481, Dec. 2000.
J. J. H. Wang, “Broadband omnidirectional helmet antennas,” IEEE AP-S Int. Symp., Albuquerque, NM, pp. 2129-2132, July 2006.
J. Y. Park, H. K. Ryu, and J. M. Woo, “Helmet installed antenna using a half-wavelength circular loop antenna,” IEEE AP-S Int. Symp., Honolulu, HI, pp. 4176-4179, June 2007.
T. Nakao, H. T. Nguyen, M. Nagatoshi, and H. Morishita, “Fundamental study on curved folded dipole antenna,” IEEE AP-S Int. Symp., Chicago, IL, pp. 1-2, July 2012.
Y. Saita, T. Ito, N. Michishita, and H. Morishita, “Low frequency inverted-F antenna on hemispherical ground plane,” Int. Symp. Antennas Propag., Kaohsiung, Taiwan, pp. 183-184, Dec. 2014.
N. Nishiyama, N. Michishita, and H. Morishita, “SAR reduction of helmet antenna composed of folded dipole with slit-loaded ring,” Int. Symp. Antennas Propag., Hobart, Australia, pp. 1-2, Nov. 2015.
R. F. Harrington and J. R. Mautz, “The theory of characteristic modes for conducting bodies,” IEEE Trans. Antennas Propag., vol. 19, no. 5, pp. 622- 628, Sept. 1971.
M. Vogel, G. Gampala, D. Ludick, and C. J. Reddy, “Characteristic mode analysis: Putting physics back into simulation,” IEEE Antennas Propag. Mag., vol. 57, no. 2, pp. 307-317, Apr. 2015.
A. Araghi and G. Dadashzadeh, “Detail-oriented design of a dual-mode antenna with orthogonal radiation patterns utilizing theory of characteristic modes,” ACES Journal, vol. 28, no. 10, pp. 952- 959, Oct. 2013.
M. M. Elsewe and D. Chatterjee, “Ultra-wide bandwidth enhancement of single-layer single-feed patch antenna using the theory of characteristic modes,” ACES Journal, vol.33, no.3, pp.363-366, March 2018.