The position perturbations of linear antenna elements are used for designing non-uniformly spaced reconfigurable antennas radiating with multiple pattern such that the same amplitude distribution and perturbed positions produces either a pencil or a flat topped beam, the difference being dependent upon phase distribution of the array. The perturbation method consists of inducing small perturbations in the element positions of a linear array to obtain the desired patterns and offer the flexibility of simple design and is similar to other adaptive techniques like phase only or phase/amplitude synthesis. The problem of finding the element position perturbations is treated as a non linear problem and has been solved using a the generalized generation gap steady state genetic algorithm (G3-GA) using parent centric crossover. In the G3-GA approach the population diversity versus selection pressure problem considers both the parent selection and the replacement plans of GA. The positionphase synthesis method using the G3-GA approach is compared with the G3-GA phase-only synthesis technique. It is seen that, an optimal set of element-perturbed positions in a constrained position range with uniform amplitude, unequally spaced elements with unequal phases has the potential to overcome the design challenge of phase only syntheses that uses a larger number of elements to get the same desired side lobe level. Further when the main beam is scanned it is found that the proposed method can maintain a sidelobe level without distortion during beam steering for the angular positions studied.
2. Kumar, B. P. and G. R. Brenner, "Design of unequally spaced arrays for improved performance," IEEE Trans. Antennas Propag., Vol. 47, No. 32, 511-523, 1999.
doi:10.1109/8.768787
3. Bae, J.-H., K.-T. Kim, J.-H. Lee, H.-T. Kim, and J.-I. Choi, "Design of steerable non-uniform linear array geometry for sidelobe reduction," Microwave and Optical Technology Letters, Vol. 36, No. 5, 363-367, 2003.
doi:10.1002/mop.10765
4. Unz, H., "Linear arrays with arbitrarily distributed elements," IEEE Trans. Antennas Propag., Vol. 8, No. 2, 222-223, 1960.
doi:10.1109/TAP.1960.1144829
5. Harrington, R. F., "Sidelobe reduction by nonuniform element spacing," IEEE Trans. Antennas Propag., Vol. 9, No. 2, 187, 1961.
doi:10.1109/TAP.1961.1144961
6. Miller, E. K. and D. M. Goodman, "A pole zero modelling approach to linear array synthesis. I. The unconstrained solution," Radio Sci., Vol. 18, 57-69, 1983.
doi:10.1029/RS018i001p00057
7. Mailloux, R. J. and E. Cohen, "Statistically thinned arrays with quantized element weights," IEEE Trans. Antennas Propag., Vol. 39, 436-447, 1991.
doi:10.1109/8.81455
8. Lo, Y. T. and S. W. Lee, "A study of space-tapered arrays," IEEE Trans. Antennas Propag., Vol. 14, 22-30, 1966.
doi:10.1109/TAP.1966.1138612
9. Mahanti, G. K., N. Pathak, and P. Mahanti, "Synthesis of thinned linear antenna arrays with fixed sidelobe level using real coded genetic algorithm," Progress In Electromagnetics Research, Vol. 75, 319-328, 2007.
doi:10.2528/PIER07061304
10. Donelli, M., S. Caorsi, F. DeNatale, M. Pastorino, and A. Massa, "Linear antenna synthesis with a hybrid genetic algorithm," Progress In Electromagnetics Research, Vol. 49, 1-22, 2004.
doi:10.2528/PIER03121301
11. Babayigit, B., A. Akdagli, and K. Guney, "A clonal selection algorithm for null synthesizing of linear antenna arrays by amplitude control," Journal of Electromagnetic Waves and Applications, Vol. 20, 1007-1020, 2006.
doi:10.1163/156939306776930222
12. Guney, K. and M. Onay, "Amplitude-only pattern nulling of linear antenna arrays with the use of bees algorithm," Progress In Electromagnetics Research, Vol. 70, 21-36, 2007.
doi:10.2528/PIER07011204
13. Haupt, L. R., "Phase-only adaptive nulling with a genetic algorithm," IEEE Trans. Antennas Propag., Vol. 45, No. 6, 1009-1015, 1997.
doi:10.1109/8.585749
14. Ares, F., J. A. Rodriguez, E. Villanueva, and S. R. Rengarajan, "Genetic algorithms in the design and optimization of antenna array patterns," IEEE Trans. Antennas Propag., Vol. 47, 506-510, 1999.
doi:10.1109/8.768786
15. Dawoud, M. and M. Nuruzzaman, "Null steering in rectangular planer arrays by amplitude control using genetic algorithms," Int. J. Electronics, Vol. 87, No. 12, 1473-1484, 2000.
doi:10.1080/00207210050192498
16. Chung, Y. C. and R. L. Haupt, "Amplitude and phase adaptive nulling with a genetic algorithm," Journal of Electromagnetic Waves and Applications, Vol. 14, 631-649, 2000.
doi:10.1163/156939300X01337
17. Guney, K. and A. Akdagli, "Null steering of linear antenna arrays using modified tabu search algorithm," Progress In Electromagnetics Research, Vol. 33, 167-182, 2001.
doi:10.2528/PIER00121402
18. Lee, K. C. and J. Y. Jhang, "Application of particle swarm algorithm to the optimization of unequally spaced antenna arrays," Journal of Electromagnetic Waves and Applications, Vol. 20, No. 14, 2001-2012, 2006.
doi:10.1163/156939306779322747
19. Boeringer, D. W. and D. H. Werner, "Particle swarm optimization versus genetic algorithms for phased array synthesis," IEEE Trans. Antennas Propag., Vol. 52, 771-779, 2004.
doi:10.1109/TAP.2004.825102
20. Chen, T. B., Y. L. Dong, Y. C. Jiao, and F. S. Zhang, "Synthesis of circular antenna array using crossed particle swarm optimization algorithm," Journal of Electromagnetic Waves and Applications, Vol. 20, 1785-1795, 2006.
doi:10.1163/156939306779292273
21. Akdagli, A., K. Guney, and D. Karaboga, "Pattern nulling of linear antenna arrays by controlling only the element positions with the use of improved touring ant colony optimization algorithm," Journal of Electromagnetic Waves and Applications, Vol. 16, 1423-1441, 2002.
doi:10.1163/156939302X00066
22. Akdagli, A., K. Guney, and B. Babayigit, "Clonal selection algorithm for design of reconfigurable antenna array with discrete phase shifters," Journal of Electromagnetic Waves and Applications, Vol. 21, No. 2, 215-227, 2007.
doi:10.1163/156939307779378808
23. Durr, M., A. Trastoy, and F. Ares, "Multiple-pattern linear antenna arrays with single prefixed amplitude distributions: Modified Woodward-Lawson synthesis," Electronics Letters, Vol. 36, No. 16, 1345-1346, 2000.
doi:10.1049/el:20000980
24. Bucci, O. M., G. Mazzarella, and G. Panariello, "Reconfigurable arrays by phase-only control," IEEE Trans. Antennas and Propag., Vol. 39, No. 7, 919-925, 1991.
doi:10.1109/8.86910
25. Gies, D. and Y. Rahmat-Samii, "Particle swarm optimization for reconfigurable phase differentiated array design," Microwave and Optical Technology Letters, Vol. 38, 168-175, 2003.
doi:10.1002/mop.11005
26. Chakrabarty, A., B. N. Das, and G. S. Sanyal, "Beam shaping using nonlinear phase distribution in a uniformly spaced array," IEEE Trans. Antennas and Propag., Vol. 30, 1031-1034, 1982.
doi:10.1109/TAP.1982.1142917
27. Baskar, S., A. Alphones, and P. N. Suganthan, "Genetic algorithm based design of a reconfigurable antenna array with discrete phase shifter," Microwave and Optical Technology Letters, Vol. 45, 461-465, 2005.
doi:10.1002/mop.20853
28. Trastoy, A., Y. Rahmat-Samii, F. Ares, and E. Moreno, "Two pattern linear array antenna: synthesis and analysis of tolerance," IEE Proc. Microw. Antennas Propag., Vol. 151, 127-130, 2004.
doi:10.1049/ip-map:20040175
29. Diaz, X., J. A. Rodriguez, F. Ares, and E. Moreno, "Design of phase-differentiated multiple-pattern antenna arrays," Microwave and Optical Technology Letters, Vol. 26, 52-53, 2000.
doi:10.1002/(SICI)1098-2760(20000705)26:1<52::AID-MOP16>3.0.CO;2-0
30. Mahanti, G. K., A. Chakraborty, and S. Das, "Design of fully digital controlled reconfigurable array antennas with fixed dynamic range ratio," Journal of Electromagnetic Waves and Applications, Vol. 21, No. 1, 97-106, 2007.
doi:10.1163/156939307779391768
31. Shore, R., "Nulling at symmetric pattern location with phase only weight control," IEEE Trans. Antennas and Propag., Vol. 32, No. 5, 530-533, 1984.
doi:10.1109/TAP.1984.1143360
32. Trastoy, A. and F. Ares, "Phase-only control of antenna sum patterns," Progress In Electromagnetics Research, Vol. 30, 47-57, 2001.
doi:10.2528/PIER00012401
33. Shore, R. A., "Nulling at symmetric pattern location with phase only weight control," IEEE Trans. Antennas Propag., Vol. 32, 530-533, 1984.
doi:10.1109/TAP.1984.1143360
34. Tennant, A., M. M. Dawoud, and A. P. Anderson, "Array pattern nulling by element position perturbations using a genetic algorithm," Electronics Letters, Vol. 30, 174-176, 1994.
doi:10.1049/el:19940139
35. Deb, K., A. Anand, and D. Joshi, "A computationally efficient evolutionary algorithm for real-parameter optimization," KanGAL Report, 2002003.