This paper deals with the experimental validation of an effective near-field-far-field transformation technique with helicoidal scanning particularly suitable for electrically long antennas, whose validity has been numerically assessed in a previous authors' paper. Such a technique relies on the results relevant to the nonredundant sampling representations of the electromagnetic fields and makes use of an optimal sampling interpolation algorithm, which allows the reconstruction of the near-field data needed by the near-field-far-field transformation with cylindrical scan. The use of a prolate ellipsoid instead of a sphere to model an elongated antenna allows one to consider measurement cylinders with a diameter smaller than the antenna height, thus reducing the error related to the truncation of the scanning zone. Moreover, a significant reduction of the needed near-field data is also obtained. The comparison of the far-field patterns reconstructed from the acquired helicoidal measurements with those obtained from the data directly measured on the classical cylindrical grid assesses the effectiveness of the near-field-far-field transformation using this innovative scanning technique. At last, its validity is further confirmed by the very good agreement with the direct far-field measurements.
2. Bucci, O. M., C. Gennarelli, G. Riccio, and C. Savarese, "Probe compensated NF-FF transformation with helicoidal scanning," Journal of Electromagnetic Waves and Applications, Vol. 14, No. 4, 531-549, 2000.
3. Bucci, O. M., C. Gennarelli, G. Riccio, and C. Savarese, "\Nonredundant NF-FF transformation with helicoidal scanning," Journal of Electromagnetic Waves and Applications, Vol. 15, No. 11, 1507-1519, 2001.
doi:10.1163/156939301X00076
4. Bucci, O. M., F. D'Agostino, C. Gennarelli, G. Riccio, and C. Savarese, "Probe compensated FF reconstruction by NF planar spiral scanning," IEE Proc. --- Microw., Ant. Prop., Vol. 149, 119-123, April 2002.
5. Bucci, O. M., F. D'Agostino, C. Gennarelli, G. Riccio, and C. Savarese, "NF-FF transformation with spherical spiral scanning," IEEE Antennas Wireless Propagat. Lett., Vol. 2, 263-266, 2003.
doi:10.1109/LAWP.2003.820710
6. D'Agostino, F., F. Ferrara, C. Gennarelli, G. Riccio, and C. Savarese, "Directivity computation by spherical spiral scanning in NF region," Journal of Electromagnetic Waves and Applications, Vol. 19, 1343-1358, 2005.
doi:10.1163/156939305775525927
7. D'Agostino, F., C. Gennarelli, G. Riccio, and C. Savarese, "Theoretical foundations of near-field-far-field transformations with spiral scannings," Progress In Electromagnetics Research, Vol. 61, 193-214, 2006.
doi:10.2528/PIER06021401
8. Yaccarino, R. G., L. I. Williams, and Y. Rahmat-Samii, "Linear spiral sampling for the bipolar planar antenna measurement technique," IEEE Trans. Antennas Propagat., Vol. 44, 1049-1051, July 1996.
9. Bucci, O. M., C. Gennarelli, and C. Savarese, "Representation of electromagnetic fields over arbitrary surfaces by a finite and nonredundant number of samples," IEEE Trans. Antennas Propagat., Vol. 46, 351-359, March 1998.
doi:10.1109/8.662654
10. Bucci, O. M., C. Gennarelli, and C. Savarese, "Fast and accurate near-field-far-field transformation by sampling interpolation of plane-polar measurements," IEEE Trans. Antennas Propagat., Vol. 39, 48-55, January 1991.
doi:10.1109/8.64434
11. Gennarelli, C., G. Riccio, V. Speranza, and C. Savarese, "Fast and accurate interpolation of radiated fields over a cylinder," Progress In Electromagnetics Research, Vol. 8, 349-375, 1994.
12. Leach, Jr., W. M. and D. T. Paris, "Probe compensated NF measurements on a cylinder," IEEE Trans. Antennas Propagat., Vol. 21, 435-445, July 1973.
13. D'Agostino, F., F. Ferrara, C. Gennarelli, R. Guerriero, and M. Migliozzi, "Near-field-far-field transformation technique with helicoidal scanning for elongated antennas," Progress In Electromagnetics Research B, Vol. 4, 249-261, 2008.
doi:10.2528/PIERB08011503
14. D'Agostino, F., F. Ferrara, C. Gennarelli, R. Guerriero, and M. Migliozzi, "The unified theory of near-field-far-field transformations with spiral scannings for nonspherical antennas," Progress In Electromagnetics Research B, Vol. 14, 449-477, 2009.
doi:10.2528/PIERB09031808
15. D'Agostino, F., F. Ferrara, C. Gennarelli, R. Guerriero, and M. Migliozzi, "An effective NF-FF transformation technique with planar spiral scanning tailored for quasi-planar antennas," IEEE Trans. Antennas Propagat., Vol. 56, 2981-2987, September 2008.
doi:10.1109/TAP.2008.928786
16. Costanzo, S. and G. D. Massa, "Far-field reconstruction from phaseless near-field data on a cylindrical helix," Journal of Electromagnetic Waves and Applications, Vol. 18, No. 8, 1057-1071, 2004.
doi:10.1163/1569393042955414
17. Costanzo, S. and G. D. Massa, "Near-field to far-field transformation with planar spiral scanning," Progress In Electromagnetics Research, Vol. 73, 49-59, 2007.
doi:10.2528/PIER07031903
18. Sten, J. C.-E. and E. A. Marengo, "Transformation formulas for spherical and spheroidal multipolefields," AEU Int. J. Electron. Commun., Vol. 61, No. 4, 262-269, 2007.
doi:10.1016/j.aeue.2006.04.005
19. Bucci, O. M., G. D'Elia, and M. D. Migliore, "Advanced field interpolation from plane-polar samples: Experimental verification," IEEE Trans. Antennas Propagat., Vol. 46, 204-210, February.
20. D'Agostino, F., F. Ferrara, C. Gennarelli, G. Riccio, and C. Savarese, "NF-FF transformation with cylindrical scanning from a minimum number of data," Microw. Opt. Technol. Lett. , Vol. 35, 264-370, November 2002.
doi:10.1002/mop.10578
Submit
