A Guide to Performing Automatic 2D Near-Field Planar Measurements Using an Outdated Robotic Arm

Authors

  • Alan Fernando Ney Boss Instituto Nacional de Pesquisas Espaciais – Laboratório de Integração e Teste – São José dos Campos/SP – Brazil. https://orcid.org/0000-0002-4600-5443
  • Eduardo Alan de Andrade Cruz Instituto Nacional de Pesquisas Espaciais – Laboratório de Integração e Teste – São José dos Campos/SP – Brazil. https://orcid.org/0009-0002-9218-5008
  • Alexandre dos Santos Andrade Instituto Nacional de Pesquisas Espaciais – Laboratório de Integração e Teste – São José dos Campos/SP – Brazil. https://orcid.org/0009-0003-2422-5490
  • Guilherme Nader Kawassaki Instituto Nacional de Pesquisas Espaciais – Laboratório de Integração e Teste – São José dos Campos/SP – Brazil. https://orcid.org/0009-0009-3556-9110
  • Mirabel Cerqueira Rezende Universidade Federal de São Paulo – Laboratório de Tecnologia de Polímeros e Biopolímeros – São José dos Campos/SP – Brazil. https://orcid.org/0000-0002-3735-8765
  • Mauricio Ribeiro Baldan Instituto Nacional de Pesquisas Espaciais – Coordenação de Pesquisa Aplicada e Desenvolvimento Tecnológico – São José dos Campos/SP – Brazil. https://orcid.org/0000-0001-7605-1064

Keywords:

Antenna, Lens, Python, Automation

Abstract

Near-field (NF) measurements are commonly used to predict the far-field (FF) of an antenna through NF to FF conversion. Conventional automated setup measurements use linear robotic systems that occupy a large space and are limited to scan multiple planes and co- and cross-polar in a sequence. Modern systems use a robotic arm to overcome this issue, but it is very expensive. This work explains how to perform 2D NF measurements using an outdated robotic arm controlled by Python and Arduino. This low-cost system was validated through horn lens measurements from X- to Ka-band. The maximum difference in beam waist between theoretical and measured was ~3.17 mm for the X-band horn lens antenna due to the focal distance difference of ~11.11 mm. The source of errors and limitations is discussed here. The measured data along with the Python code to generate 2D color maps are available on GitHub. Although it involves more complexity and additional steps compared to commercial systems, this budget system provided good agreement with the theoretical values of the horn lens antennas, becoming a viable alternative to perform raster NF measurements over a three-dimensional volume. Further works may include implementations of cylindrical or spherical measurements.


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Published

2025-11-07

Issue

Vol. 17 (2025)

Section

Original Papers

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Copyright (c) 2025 Alan Fernando Ney Boss, Eduardo Alan de Andrade Cruz, Alexandre dos Santos Andrade, Guilherme Nader Kawassaki, Mirabel Cerqueira Rezende, Mauricio Ribeiro Baldan

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