volume | PIER Journals

2004-12-13

On the Influence of Incomplete Radiation Pattern Data on the Accuracy of a Spherical Wave Expansion

Paivi Koivisto,

Dr. Paivi Koivisto

VTT Information Technology, Telecommunications

Finland

Homepage

Johan Sten

Dr. Johan Sten

VTT Information Technology

Finland

Homepage

Progress In Electromagnetics Research, Vol. 52, 185-204, 2005

doi:10.2528/PIER04080902

Abstract

The accuracy of a spherical wave expansion is examined when the expansion is calculated from incomplete data of the radiation pattern, i.e., when field data on a part of the far-field sphere is missing. The effect of antenna size and truncation index on the interpolation capacity of a SWE is examined by using an analytical expression for the radiation pattern of wire antennas of different lengths. The error of the SWE is seen to increase drastically when the smallest diameter of the dead zone surpasses the length of a period of the highest included wave function. The influence of the size and shape of the dead zone is studied by the aid of a measured pattern, of which a part of the field data is ignored. Two different ways are proposed for estimating the accuracy of the obtained SWE in a practical instance, when the field in the dead zone is unknown.

Citation

Copy Export

Paivi Koivisto, and Johan Sten, "On the Influence of Incomplete Radiation Pattern Data on the Accuracy of a Spherical Wave Expansion," Progress In Electromagnetics Research, Vol. 52, 185-204, 2005.
doi:10.2528/PIER04080902

References

1. Koivisto, P., "Reduction of errors in antenna radiation patterns using optimally truncated spherical wave expansion," Progress In Electromagnetics Research (PIER), Vol. 47, 313-333, 2004.
doi:10.2528/PIER03120301

2. Koivisto, P., "Demonstration of reflection error reduction in antenna radiation patterns using spherical wave expansion," Microwave and Optical Technology Letters, 2004.

3. Hansen, J. E. (Ed.), Spherical Near-Field Antenna Measurements, IEE Electromagnetic Waves Series 26, Peter Peregrinus Ltd., London, United Kingdom, 1988.

4. Harrington, R. F., Time-Harmonic Electromagnetic Fields, McGraw-Hill, 1961.

5. Stratton, J. A., Electromagnetic Theory, 1st Ed., McGraw-Hill, New York and London, 1941.

6. Papas, C. H., Theory of Electromagnetic Wave Propagation, Dover Publications, Inc., New York, 1988.

7. Mekki-Kaidi, M., D. Lautru, F. Bancet, and V. Fouad Hanna, "A matrix inversion technique for the spherical modal decomposition field solution applied on the characterization of antennas in their environment," Microwave and Optical Technology Letters, Vol. 41, No. 5, 336-341, 2004.
doi:10.1002/mop.20134

8. Koivisto, P., "Elimination of rotation axes offset error in antenna radiation pattern measurements using spherical wave expansion," Submitted for publication in Int. J. Electron. Commun. (AEü)..