A new excitation technique for wide-band short backfire antennas

A new excitation technique is developed to improve the impedance bandwidth and to lower the manufacturing cost of a short backfire antenna (SBA). The new excitation structure consists of a planar monopole and a microstrip feed line, both of which are printed on the same dielectric substrate. By splitting the printed monopole with a slot, a wide-band performance can be achieved. The new split-monopole-excited SBA achieves an impedance bandwidth of about 15% [voltage standing wave ratio (VSWR <2)] while maintaining good radiation performance. As an example, an SBA configuration with the new excitation topology was designed and measured at the 5 GHz UNII band, and good agreement was observed between the simulation and experiment. The effects of the geometric parameters of the excitation structure on the impedance performance are investigated and the operating mechanism of the split-monopole-excited SBA is discussed. Being a low-cost, high-gain, and wide-band directional antenna, the new SBA can find applications in various wireless systems, such as LMDS, WLAN, and the emerging WiMAX networks.

[1]  H. D. Hristov,et al.  Microwave Cavity Antennas , 1989 .

[2]  Hermann W Ehrenspeck THE BACKFIRE ANTENNA, A NEW TYPE OF DIRECTIONAL LINE SOURCE , 1961 .

[3]  S. M. Cherry WiMax and Wi-Fi: Separate and Unequal , 2004 .

[4]  K. M. Chen,et al.  Radiation fields of the short-backfire antenna , 1968 .

[5]  S. Ohmori,et al.  An improvement in electrical characteristics of a short backfire antenna , 1983 .

[6]  Weng Cho Chew,et al.  Circular short backfire antenna modeling , 1992 .

[7]  R. Garg,et al.  Microstrip Antenna Design Handbook , 2000 .

[8]  Rod Waterhouse,et al.  Broadband printed sectorized coverage antennas for millimeter-wave wireless applications , 2002 .

[9]  J.S. Fu,et al.  Short backfire antennas for wireless LAN applications at millimeter-waves , 2000, IEEE Antennas and Propagation Society International Symposium. Transmitting Waves of Progress to the Next Millennium. 2000 Digest. Held in conjunction with: USNC/URSI National Radio Science Meeting (C.

[10]  C. Sabatier,et al.  T-dipole arrays for mobile applications , 2003 .

[11]  Steven J. Vaughan-Nichols,et al.  Achieving Wireless Broadband with WiMax , 2004, Computer.

[12]  Christos N. Capsalis,et al.  Rain attenuation problems affecting the performance of microwave communication systems , 1990 .

[13]  S. H. Lin,et al.  A method for calculating rain attenuation distributions on microwave paths , 1975, The Bell System Technical Journal.

[14]  Peter F. Driessen Gigabit/s indoor wireless systems with directional antennas , 1996, IEEE Trans. Commun..

[15]  Ahmed A. Kishk,et al.  Gain optimization of short-backfire antenna with different excitation types , 1986, 1986 Antennas and Propagation Society International Symposium.

[16]  M. Rayner,et al.  FD-TD design of short backfire antennas , 1997 .

[17]  John A. Strom,et al.  The Short-Backfire Antenna as an Element for High-Gain Arrays , 1971 .

[18]  J. R. James,et al.  Mobile Antenna Systems Handbook , 2001 .

[19]  K.M.K.H. Leong,et al.  Surface wave enhanced broadband planar antenna for wireless applications , 2001, IEEE Microwave and Wireless Components Letters.

[20]  Chandra,et al.  Theoretical and experimental investigations of two-dimensional waveguide-excited short backfire antenna structure , 1989 .

[21]  J. Laskar,et al.  Development of a wide-band short backfire antenna excited by an unbalance-fed H-shaped slot , 2005, IEEE Transactions on Antennas and Propagation.

[22]  Kyohei Fujimoto,et al.  Mobile Antenna Systems Handbook, Second Edition , 2001 .