Far-Field Reconstruction from a Minimum Number of Spherical Spiral Data Using Effective Antenna Modelings

Two probe-compensated near-field-far-field transforma- tions with spherical spiral scanning tailored for antennas having two of their dimensions very different from the third one are developed by properly applying the unified theory of spiral scans for nonspheri- cal antennas. One is suitable for electrically long antennas, which are considered as enclosed in a cylinder ended in two half-spheres. The other adopts a surface formed by two circular "bowls" with the same aperture diameter but different lateral bends to shape a quasi-planar antenna. These flexible modelings fit very well many actual antennas by properly setting their geometric parameters. Great reduction of the number of data to be acquired is achieved, thus significantly re- ducing the required measurement time. Numerical tests validating the accuracy of the proposed techniques and their stability with respect to random errors affecting the data are shown.

[1]  G. Riccio,et al.  Probe compensated NF-FF transformation with spherical spiral scanning , 2003, 17th International Conference on Applied Electromagnetics and Communications, 2003. ICECom 2003..

[2]  Flaminio Ferrara,et al.  Effective Antenna Modellings for NF-FF Transformations with Spherical Scanning Using the Minimum Number of Data , 2011 .

[3]  Arthur D. Yaghjw.  An Overview of Near-Field Antenna Measurements , 2009 .

[4]  Claudio Gennarelli,et al.  Theoretical Foundations of Near-Field-Far-Field Transformations with Spiral Scannings , 2006 .

[5]  Flaminio Ferrara,et al.  THE UNIFIED THEORY OF NEAR-FIELD-FAR-FIELD TRANSFORMATIONS WITH SPIRAL SCANNINGS FOR NONSPHERICAL ANTENNAS , 2009 .

[6]  Yahya Rahmat-Samii,et al.  Linear spiral sampling for the bipolar planar near-field antenna measurement technique , 1996 .

[7]  G. Riccio,et al.  Near-field-far-field transformation with spherical spiral scanning , 2003, IEEE Antennas and Wireless Propagation Letters.

[8]  O. Bucci,et al.  Representation of electromagnetic fields over arbitrary surfaces by a finite and nonredundant number of samples , 1998 .

[9]  Marco Donald Migliore,et al.  Advanced field interpolation from plane-polar samples: experimental verification , 1998 .

[10]  Ovidio Mario Bucci,et al.  Data Reduction in the Nf-Ff Transformation Technique With Spherical Scanning , 2001 .

[11]  Flaminio Ferrara,et al.  A Nonredundant Near-Field to Far-Field Transformation with Spherical Spiral Scanning for Nonspherical Antennas , 2009 .

[12]  Directivity Computation by Spherical Spiral Scanning in Near Field Region , 2005 .

[13]  E. S. Gillespie.  Special issue near-field scanning techniques , 1988 .