Abstract-In this paper, a novel ultra-wideband switched-beam antenna system based on 4×4 two-layer Butler matrix is presented and implemented to be used in hostile environment, such as underground mines. This matrix is based on the combination of a broadband twolayer slot-coupled directional coupler and a multilayer slot-coupled microstrip transition. With this configuration, the proposed matrix was designed without using any crossovers as used in conventional Butler matrices. Moreover, this new structure is compact and offers an ultra-wide bandwidth of 6 GHz. To examine the performance of the proposed matrix, experimental prototypes of the multilayer microstrip transition and the Butler matrix were fabricated and measured. Furthermore, a three 4-antenna arrays were also designed, fabricated and then connected to the matrix to form a beamforming antenna system at 3, 5.8 and 6 GHz. As a result, four orthogonal beams are produced in the band 3-9 GHz. This matrix is suitable for ultrawideband communication systems in confined areas.
1. Nerguizian, C., C. Despins, S. Affes, and M. Djadel, "Radiochannel characterization of an underground mine at 2.4 GHz wireless communication," IEEE Trans. on Wireless Commun., Vol. 4, No. 5, 2441-2453, Sep. 2005. doi:10.1109/TWC.2005.853899
2. Chao, R. Y. and K. S. Chung, "A low profile antenna array for underground mine communication," Proc. of ICCS'94, Vol. 2, 705-709, 1994. doi:10.1109/ICCS.1994.474139
3. Dessouky, M. I., H. A. Sharshar, and Y. A. Albagory, "Improving the cellular coverage from a high altitude platform by novel tapered beamforming technique," Journal of Electromagnetic Waves and Applications, Vol. 21, No. 13, 1721-1731, 2007.
4. Jeong, Y.-S. and J.-H. Lee, "Estimation of time delay using conventional beamforming-based algorithm for UWB systems," Journal of Electromagnetic Waves and Applications, Vol. 21, No. 15, 2413-2420, 2007. doi:10.1163/156939307783134281
5. Winter, J. H., "Smart antennas for wireless systems," IEEE Personal Communications, Vol. 1, 23-27, Feb. 1998. doi:10.1109/98.656155
6. Fakoukakis, F. E., S. G. Diamantis, A. P. Orfanides, and G. A. Kyriacou, "Development of an adaptive and a switched beam smart antenna system for wireless communications," Journal of Electromagnetic Waves and Applications, Vol. 20, No. 3, 399-408, 2006. doi:10.1163/156939306775701722
7. Ho, M.-J., G. L. Stuber, and M. Austin, "Performance of switchedbeam smart antennas, for cellular radio systems," IEEE Trans. Veh. Technol., Vol. 47, No. 1, 10-19, Feb. 1998. doi:10.1109/25.661027
8. Mitilineos, S. A., S. C. Thomopoulos, and C. Capsalis, "Genetic design of dual-band, switched-beam dipole arrays, with elements failure correction, retaining constant excitation coefficients," Journal of Electromagnetic Waves and Applications, Vol. 20, No. 14, 1925-1942, 2006. doi:10.1163/156939306779322738
9. Khani, H. and P. Azmi, "Performance analysis of a high data rate UWB-DTR system in dense multipath channels," Progress In Electromagnetics Research B, Vol. 5, 119-131, 2008. doi:10.2528/PIERB08021003
10. El-Fishawy, N. A., M. Shokair, and W. Saad, "Proposed MAC protocol versus IEEE 802.15.3a for multimedia transmission over UWB networks," Progress In Electromagnetics Research B, Vol. 2, 189-206, 2008. doi:10.2528/PIERB07111812
11. Xiao, S.-Q., J. Chen, X.-F. Liu, and B.-Z.Wang, "Spatial focusing characteristics of time reversal UWB pulse transmission with different antenna arrays," Progress In Electromagnetics Research B, Vol. 2, 223-232, 2008. doi:10.2528/PIERB07112203
12. Naghshvarian-Jahromi, M. and M. Tayarani, "Miniature planar UWB bandpass filters with circular slots in ground," Progress In Electromagnetics Research Letters, Vol. 3, 87-93, 2008. doi:10.2528/PIERL08020902
13. Yin, X.-C., C.-L. Ruan, C.-Y. Ding, and J.-H. Chu, "A planar U type monopole antenna for UWB applications," Progress In Electromagnetics Research Letters, Vol. 2, 1-10, 2008. doi:10.2528/PIERL07121405
14. Naghshvarian-Jahromi, M., "Compact UWB bandnotch antenna with transmission-line-FED," Progress In Electromagnetics Research B, Vol. 3, 283-293, 2008. doi:10.2528/PIERB07121407
15. Koo, B.-W., M.-S. Baek, and H.-K. Song, "Multiple antenna transmission technique for UWB system," Progress In Electromagnetics Research Letters, Vol. 2, 177-185, 2008. doi:10.2528/PIERL08011101
16. Porcino, D. and W. Hirt, "Ultra-wideband radio technology: Potential and challenges ahead," IEEE Comm. Mag., Vol. 4, No. 7, 66-74, July 2003.
17. Dogandzic, A., J. Riba, G. Seco, and A. L. Swindlehurst, "Positioning and navigation with applications to communications," IEEE Signal Proc. Magazine, Vol. 22, 10-11, July 2005.
18. Corona, A. and M. J. Lancaster, "A high-temperature superconducting superconducting," IEEE Trans. on Applied Superconductivity, Vol. 13, No. 4, Dec. 2003. doi:10.1109/TASC.2003.820507
20. Tudosie, G., H. Barth, and R. Vahldieck, "A compact LTCC Butler matrix realization for phased array applications," IEEE MTT-S Int. Microwave Symposium Digest, 441-444, June 2006. doi:10.1109/MWSYM.2006.249586
21. Bona, M., L. Manholm, J. P. Satarski, and B. Svensson, "Low-loss compact Butler matrix for a microstrip antenna," IEEE Trans. on Microwave Theory and Tech., Vol. 50, No. 9, Sep. 2002. doi:10.1109/TMTT.2002.802318
22. Wincza, K. and S. Gruszczynski, A broadband 4/spl times/4 Butler matrix for modern-day antennas, European Microwave Conference, Vol. 2, 4, Oct. 2005.
23. Macnamara, T. M., "Position and magnitudes of fixed phase shifters in Butler matrices incorporation 90◦ hybrids," IEE Proceedings, Vol. 135, No. 5, Oct. 1988.
24., IE3D 8.2, Zeland Software, Inc. Fremont, CA.
25. Tanaka, T., K. Tsunoda, and M. Aikawa, "Slot-coupled directional couplers between double-sided substrate microstrip lines and their applications ," IEEE Trans. Microwave Theory Tech., Vol. 36, 1752-1757, Dec. 1988. doi:10.1109/22.17410
27. Warns, C., W. Menzel, and H. Schumacher, "Transmission lines and passive elements for multilayer coplanar circuits on silicon," IEEE Trans. Microw. Theory Tech., Vol. 46, No. 5, 616-622, May 1998. doi:10.1109/22.668672
28. Theodorou, A. and N. Uzunoglu, "Transition properties of a vertical conductor connecting two microstrip lines at different planes," IEEE Trans. Microw. Theory Tech., Vol. 43, No. 5, 1162-1172, May 1995. doi:10.1109/22.382080
29. Chen, C., M. Tsai, and G. Alexopoulos, "Optimization of aperture transitions for multiport microstrip circuits," IEEE Trans. Microw. Theory Tech., Vol. 44, No. 12, 2457-2465, Dec. 1996. doi:10.1109/22.554578
30. Tran, A. M. and T. Itoh, "Analysis of microstrip lines coupled through an arbitrarily shaped aperture in a thick common ground plane ," IEEE MTT-S Symposium Digest, Vol. 3, 819-822, Atlanta, 1993.
31. Ivanov, T. and A. Mortazawi, "Two stage double layer microstrip spatial amplifiers," IEEE MTT-S Symposium Digest, Vol. 2, 589-592, Atlanta, May 1995.
32. Burke, J. J. and R. W. Jackson, "Surface-to-surface transition via electromagnetic coupling of microstrip and coplanar waveguide," IEEE Trans. Microwave Theory Tech., Vol. 37, 519-525, Mar. 1989. doi:10.1109/22.21623
33. Zhu, L. and K. Wu, "Ultrabroad-band vertical transition for multilayer integrated circuits," IEEE Microw. Guided Wave Lett., Vol. 9, No. 11, 453-455, Nov. 1999. doi:10.1109/75.808032
34. Nedil, M., A. T. Denidni, and L. Talbi, "Novel Butler matrix using CPW multilayer technology," IEEE Transactions on Microwave Theory and Techniques, Vol. 54, No. 1, 499-507, Jan. 2006. doi:10.1109/TMTT.2005.860490
35. Nedil, M., A. T. Denidni, and L. Talbi, Design of a broadband slot antenna fed by CPW for wireless application at 5.8 GHz, IEEE Vehicular Technology Conf., VTC2004-Spring, Vol. 1, 18-21, 2004.
36. Watanabe, K., J. Ishihara, and K. Yasumoto, "Coupled-mode analysis of a gating-assisted directional coupler using singular perturbation technique ," Journal of Electromagnetic Waves and Applications, Vol. 13, No. 12, 1681-1682, 1999. doi:10.1163/156939399X00114
37. Denidni, T. A. and T. E. Libar, "Wide band four-port Butler matrix for switched multibeam antenna arrays," IEEE Proceedings on Personal, Indoor and Mobile Radio Communications, 2461-2463, Sep. 2003. doi:10.1109/PIMRC.2003.1259161
38. Sharma, R., T. Chakravarty, S. Bhooshan, and A. B. Bhattacharyya, "Design of a novel 3 dB microstrip backward wave coupler using defected ground structure," Progress In Electromagnetics Research, Vol. 65, 261-273, 2006. doi:10.2528/PIER06100502
39. Wu, J.-J., "A multimode interference coupler with exponentially tapered waveguide," Progress In Electromagnetics Research C, Vol. 1, 113-122, 2008. doi:10.2528/PIERC08012406
40. Dall'Omo, C., T. Monediere, B. Jeko, F. Lamour, I. Wolk, and M. Elkael, "Design and realization of a 4×4 microstrip butler matrix without any crossing in millimeter-wave," Microwave and Optical Tech. Lett., Vol. 38, No. 6, Sep. 2003. doi:10.1002/mop.11090
41. Stutzman, W. L. and G. A. Thiele, Antenna Theory and Design, 2nd Ed., John Wiley & Sons, Inc., 1998.
42. Wong, M. F., V. F. Hanna, O. Picon, and H. Baudrand, "A novel coplanar-waveguide directional coupler with finite-extent backed conductor ," IEEE Trans. on Microwave. Theory and Tech., Vol. 12, 2123-2129, Dec. 1991. doi:10.1109/22.106554