The Moment Method is used to estimate the error induced by a compact measuring probe in the near-field. A crossed-dipole is used as a compact near-field measuring probe of a waveguide radiator in an infinite ground plane, since it measures both co-pole and cross-pole components simultaneously. However, due to multiple reflections between radiator and probe, in addition, mutual coupling effects between the poles, near-field values are changed. The relative sampled electric field pattern (without the probe) is compared to the relative sampled co-pole voltage pattern in the scan plane and the induced error is computed. The radiating waveguide's reflection coefficient is altered with respect to the reflection coefficient when there is no probe in the near-field. The numerical results concerning the reflection coefficient without the probe are compared to the measured values, and good agreement is observed.
2. Harrington, R. F., "Field Computation by Moment Method," Roger E. Krieger Publishing Company, USA, 1968.
3. Richmond, J. H., "Digital computer solutions of the rigorous equations for scattering problems," Proceedings of the IEEE, Vol. 53, 796-804, 1965.
doi:10.1109/PROC.1965.4057
4. Paramesha, S. and A. Chakrabarty, "Moment method analysis of rectangular waveguide as near-field measuring probe," MOTL, Vol. 48, No. 9, 2006.
5. Paramesha, S. and A. Chakrabarty, "Waveguide as a near-field measuring probe of the two-element array radiator," Progress In Electromagnetics Research B, Vol. 7, 245-255, 2008.
doi:10.2528/PIERB08032401
6. Gupta, S., A. Bhattacharya, and A. Chakrabarty, "Analysis of an open-ended waveguide radiator with dielectric plug," IEE Proc. Microwave, Antenna and Propagation, Vol. 144, No. 2, 126-130, 1997.
doi:10.1049/ip-map:19971016
7. Pisano III, F. A. and C. M. Butler, "Methods for modeling wire antenna loaded with shielded network," IEEE Trans. on Antennas and Propagation, Vol. 52, No. 4, 2004.
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