In this paper, a merged characteristic basis function method (MCBFM) is proposed to analyze the electromagnetic scattering characteristics from conducting targets. A merged characteristic basis function (M-CBF) is newly defined in the MCBFM. Considering the mutual interaction of surrounding blocks, the M-CBF is generated by merging the conventional secondary characteristic basis functions (SCBFs) and the high order characteristic basis functions (HO-CBFs) of each block in the conventional primary characteristic basis function (PCBF). Thus, the true current distribution of the targets is approached by using a single M-CBF reducing the number of CBFs when the incident plane waves (PWs) are certain. The numerical results of a PEC hexahedron demonstrate that the proposed MCBFM improves the accuracy without increasing the number of PWs and the CBFs compared to the improved primary CBFM (IP-CBFM). The results also demonstrate that the MCBFM is capable of effectively reducing the CPU time by 63.38% without losing any accuracy compared to the conventional characteristic basis function method (CBFM). Other results of a PEC cylinder demonstrate that when a considerable computational accuracy is required, the efficiency of the proposed MCBFM is the highest among these three methods.
2. Song, J. M. and W. C. Chew, "Multilevel fast-multipole algorithm for solving combined field integral equations of electromagnetic," Microwave and Optical Technology Letters, Vol. 10, 14-19, 1995.
doi:10.1002/mop.4650100107
3. Song, J., C. C. Lu, and W. C. Chew, "Multilevel fast multipole algorithm for electromagnetic scattering by large complex objects," IEEE Tansactions on Antennas and Propagation, Vol. 45, 1488-1493, 1997.
doi:10.1109/8.633855
4. Prakash, V. V. S. and R. Mittra, "Characteristic basis function method: A new technique for efficient solution of method of moments matrix equations," Microwave and Optical Technology Letters, Vol. 36, 95-100, 2003.
doi:10.1002/mop.10685
5. Sun, Y. F., C. H. Chan, and R. Mittra, "Characteristic basis function method for solving large problems arising in dense medium scattering," IEEE Antennas and Propagation Society International Symposium, Vol. 2, 1068-1071, 2003.
6. Tanaka, T., Y. Nishioka, and Y. Inasawa, "Verification of the PMCHWT-CBFM for scattering analysis of a microstrip array antenna," The 8th European Conference on Antennas and Propagation, 3232-3236, 2014.
doi:10.1109/EuCAP.2014.6902517
7. Tiberi, G., M. Degiorgi, and A. Monorchio, "A class of physical optics-SVD derived basis functions for solving electromagnetic scattering problems," IEEE Antennas and Propagation Society International Symposium, 143-146, 2005.
8. Degiorgi, M., G. Tiberi, and A. Monorchio, "An SVD-based method for analyzing electromagnetic scattering from plates and faceted bodies using physical optics bases," IEEE Antennas and Propagation Society International Symposium, 147-150, 2005.
9. Maaskant, R., R. Mittra, and A. Tijhuis, "Fast analysis of large antenna arrays using the characteristic basis function method and the adaptive cross approximation algorithm," IEEE Transactions on Antennas and Propagation, Vol. 56, 3440-3451, 2009.
10. De Gregorio, M., G. Tiberi, and A. Monorchio, "Solution of wide band scattering problems using the characteristic basis function method," IET Microwaves Antennas and Propagation, Vol. 6, 60-66, 2012.
doi:10.1049/iet-map.2011.0309
11. Lucente, E., A. Monorchio, and R. Mittra, "An iteration-free MoM approach based on excitation independent characteristic basis functions for solving large multiscale electromagnetic scattering problems," IEEE Transactions on Antennas and Propagation, Vol. 56, 999-1007, 2008.
doi:10.1109/TAP.2008.919166
12. Wang, Z. G., Y. F. Sun, and G. H.Wang, "Fast analyses of electromagnetic scatteringcharacteristics from conducting targets using improved and the adaptive cross approximation algorithm," Acta Physica Sinica, Vol. 62, 204102, 2013.
13. Hay, S. G., J. D. O’Sullivan, and A. Mittra, "Connected patch array analysis using the characteristic basis function method," IEEE Transactions on Antennas and Propagation, Vol. 59, 1828-1837, 2011.
doi:10.1109/TAP.2011.2123867
14. Konno, K. and Q. Chen, "The numerical analysis of an antenna near a dielectric object using the higher-order characteristic basis function method combined with a volume integral equation," IEICE Transactions on Communications, Vol. E97B, 2066-2073, 2014.
doi:10.1587/transcom.E97.B.2066
15. Tanaka, T., Y. Inasawa, and Y. Nishioka, "Improved primary characteristic basis function method for monostatic radar cross section analysis of specific coordinate plane," IEICE Transactions on Electronics, Vol. E99C, 28-35, 2016.
doi:10.1587/transele.E99.C.28