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IEEE Transactions on Antennas and Propagation
Volume 46 Number 6, June 1998

Table of Contents for this issue

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Realization of Dual-Frequency and Wide-Band VSWR Performances Using Normal-Mode Helical and Inverted-F Antennas

Hisamatsu Nakano, Fellow, IEEE, Noriaki Ikeda, Yu-Yuan Wu, Ryota Suzuki, Hiroaki Mimaki, Member, IEEE, and Junji Yamauchi, Member, IEEE

Page 788.

Abstract:

The effects of parasitic elements on the voltage standing wave ratios (VSWR's) of two antennas are investigated. First, a parasitic monopole is used for a normal-mode helical antenna. The VSWR investigation shows that dual-frequency operation is obtained by the parasitic element effects. The dual-frequency operation is revealed as a function of monopole position above a ground plane (monopole height). As the monopole height decreases, the separation of a higher resonance frequency f_H from a lower resonance frequency f_L increases. For a monopole length of L_{MP} \approx 0.4\lambda_{{HX}}, where \lambda_{{HX}} is the resonance wavelength of the helix, the frequency bandwidth for a VSWR = 2 criterion is 12.5% in the lower frequency f_L region and 5.2% in the higher frequency f_H region, with a frequency separation ratio of f_H/f_L = 2.14. Secondly, L-figured parasitic elements are used for an inverted-F antenna (IFA). The parasitic elements improve the VSWR performance. The frequency bandwidth for a VSWR = 2 criterion is approximately two times as wide as that of the single IFA. It is also found that bending the horizontal sections of the IFA and parasitic elements contributes to reducing the antenna size while not significantly deteriorating the VSWR bandwidth. The radiation patterns are also presented and discussed.

References

  1. J. D. Kraus, Antennas, 2nd ed.New York: McGraw-Hill, 1988.
  2. R. King, C. W. Harrison, Jr., and D. H. Denton, Jr., "Transmission-line missile antennas," IEEE Trans. Antennas Propagat., vol. 8, pp. 88-90, Jan. 1960.
  3. J. S. Colburn and Y. Rahmat-Samii, "Analysis of a square helix applicable to the personal satellite communication handset," in IEEE AP-S Symp. Dig., Newport Beach, CA, June 1995, pp. 1418-1421.
  4. K. Fujimoto, A. Henderson, K. Hirasawa, and J. R. James, Small Antennas.New York: Research Studies Press, 1987, pp. 116-135.
  5. H. Nakano and H. Mimaki, "Normal mode helical antenna with inserted cylindrical conductor," in Proc. IEICE Fall Conf., Tokyo, Japan, Sept. 1992, B-65, p. 65.
  6. --, "A normal mode helical antenna with a parasitic wire element," in Proc. IEICE Fall Conf., Sendai, Japan, Sept. 1994, B-79, p. 79.
  7. H. Nakano, N. Ikeda, H. Mimaki, and J. Yamauchi, "A normal mode helical antenna (II)," in Proc. IEICE Gen. Conf., Fukuoka, Japan, Mar. 1995, B-155, p. 155.
  8. P. Erätuuli, P. Haapala, and P. Vainikainen, " Dual-frequency wire antennas," Inst. Electron. Eng. Electron. Lett., vol. 32, pp. 1051-1052, June 1996.
  9. E. A. Wolff, Antenna Analysis.Boston, MA: Artech House, 1988, ch. 3.
  10. R. J. F. Guertler, "Isotropic transmission-line antenna and its toroid-pattern modification," IEEE Trans. Antennas Propagat., vol. 25, pp. 386-392, May 1977.
  11. T. Tsukiji, "Characteristics of twin rectangular loop antenna and complex loop antennas," IECE Tech. Rep. Antennas Propagat., vol. AP87-43, pp. 63-70, June 1987.
  12. K. Fujimoto and J. R. James, Mobile Antenna Systems Handbook.Boston, MA: Artech House, 1994, p. 160.
  13. H. Mishima and T. Taga, "Mobile antenna and duplexer for 800 MHz band mobile telephone system," in IEEE AP-S Int. Symp. Dig., Quebec, Canada, June 1980, pp. 508-511.
  14. H. Nakano, Y. Wu, H. Mimaki, and J. Yamauchi, "An inverted-F antenna with parasitic elements," in Proc. IEICE Fall Conf., Sendai, Japan, Sept. 1994, B-35, p. 35.
  15. --, "An inverted-F antenna with parasitic elements (II)," in Proc. IEICE Gen. Conf., Fukuoku, Japan, Mar. 1995, B-167, p. 167.
  16. K. Virga and Y. Rahmat-Samii, "An enhanced-bandwidth integrated dual L antenna for mobile communications systems--Design and measurement," in IEEE AP-S Int. Symp. Dig., Newport Beach, CA, June 1995, pp. 1120-1123.
  17. E. Yamashita, Ed., Analysis Methods for Electromagnetic Wave Problems.Boston, MA: Artech House, 1995, vol. 2, ch. 3.
  18. R. F. Harrington, Field Computation by Moment Methods.New York: Macmillan, 1968.