Near-field measurement of an offset reflector antenna at a spherical range in anechoic chamber

Citation Author(s):
Álvarez López
Universidad de Oviedo
Queen’s University Belfast
Laviada Martínez
Universidad de Oviedo
Las-Heras Andrés
Universidad de Oviedo
Submitted by:
Yuri Alvarez-Lopez
Last updated:
Mon, 12/04/2023 - 15:48
Data Format:
0 ratings - Please login to submit your rating.


This dataset corresponds to the near field (NF) measurements of a 70 cm diameter offset reflector antenna, fed with a circularly polarized helix antenna, working at 4650 MHz [1,2].

The reflector antenna was measured at the spherical range in an anechoic chamber of the University of Oviedo, in Spain. This anechoic chamber has a roll over azimuth positioner that enables full spherical acquisions. Two different measurement distances were considered, R1 = 3.198 m and R2 = 5.191 m. Samples on both spherical acquisition surfaces were taken according to a sampling rate of 1 degree in theta (or azimuth axis), and 3 degrees in phi (roll axis). The two tangential components of the electric field (Eth, Eph) were measured.

This dataset can be used for testing near-field-to-far-field (NF-FF) transformation techniques [3]. Besides, measurements are provided at two different distances, thus enabling the assessment of amplitude-only antenna diagnostics and NF-FF transformation methods [4-7].

[1] García Fernández, M.; Álvarez López, Y.; Las-Heras, F. Dual-Probe Near-Field Phaseless Antenna Measurement System on Board a UAV. Sensors 2019, 19, 4663.

[2] M. G. Fernández, Y. Álvarez López and F. L. -H. Andrés, "Advances in Antenna Measurement and Characterization Using Unmanned Aerial Vehicles," 2019 13th European Conference on Antennas and Propagation (EuCAP), Krakow, Poland, 2019, pp. 1-5.

[3] Y. Alvarez, F. Las-Heras and M. R. Pino, "Reconstruction of Equivalent Currents Distribution Over Arbitrary Three-Dimensional Surfaces Based on Integral Equation Algorithms," in IEEE Transactions on Antennas and Propagation, vol. 55, no. 12, pp. 3460-3468, Dec. 2007,

[4] C. Cappellin, A. Frandsen and O. Breinbjerg, "Application of the SWE-to-PWE antenna diagnostics technique to an offset reflector antenna", IEEE Antennas Propag. Mag., vol. 50, no. 5, pp. 204-213, Oct. 2008.

[5] Y. Alvarez, F. Las-Heras, and M. R. Pino, “The sources reconstruction method for amplitude-only field measurements,” IEEE Transactions on Antennas and Propagation, vol. 58, no. 8, pp. 2776–2781, 2010.

[6] Zhi-Xiang Xie, Yun-Hua Zhang, Si-Yuan He, Guo-Qiang Zhu, "A Novel Method for Source Reconstruction Based on Spherical Wave Expansion and NF-FF Transformation Using Amplitude-Only Data", IEEE Transactions on Antennas and Propagation, vol.67, no.7, pp.4756-4767, 2019.

[7] Fernando Rodríguez Varela, Javier Fernandez Álvarez, Belén Galocha Iragüen, Manuel Sierra Castañer, Olav Breinbjerg, "Numerical and Experimental Investigation of Phaseless Spherical Near-Field Antenna Measurements", IEEE Transactions on Antennas and Propagation, vol.69, no.12, pp.8830-8841, 2021.


The submitted files containing the measurements are in *.txt format. Each file corresponds to one measurement distance. Data are arranged into a matrix form, where the first column corresponds to the theta angle values, the second is the phi angle, the third and the fourth columns are the Etheta component (real and imaginary format), and the fifth and sixth are the Ephi component (also in real and imaginary).

A *.m Matlab script is provided. It can be used to import the data and plot them (spherical visualization of the copolar and crosspolar circular components, in dB).

For questions or issues, please do not hesitate to contact us. Thank you.

Yuri Alvarez Lopez,

Funding Agency: 
Ministerio de Ciencia e Innovación of Spain, Agencia Estatal de Investigación of Spain, and Fondo Europeo de Desarrollo Regional (FEDER)
Grant Number: 
PID2021-122697OB-I00 (“META-IMAGER”)