Abstract:In areas such as microwave remote sensing and deep space exploration, it is expected that accurate antenna radiation patterns can be obtained in order to acquire realistic observations by inverting the visibility function. Therefore, there is an urgent demand of quantitative measurement error from different methods to measure radiation patterns. From the perspective of metrology, quantitative studies by comparing between precision measurements and simulations are conducted. The precise measured data for the standard gain horn antenna show that among far-field method, planar near-field method and spherical near-field method, the conclusions can be drawn : 1) the spherical near-field method has the best zero-depth effect, the far-field method is the worst, and the planar near-field method is in between the two. 2) The effective angular range of the plane near-field method is located within ±60°, beyond this range, the truncation error increases sharply and becomes invalid. 3) the far-field method shows obvious ripple outside the angular range ±80°. Another comparison shows that the spherical near-field method and the compact field method have a better agreement effect, but the curves from the former are smoother. For linear array antennas, the simulated technology is used to study comparatively the accuracy of the three near-field methods. The quantitative research results can be a guide to select the right antenna measurement system and improve the accuracy of radiation pattern measurement.
XU Z H,LI N J,HU C F,et al. Antenna pattern correction in near-field scattering measurement [J]. Systems Engineering and Electronics, 2017, 39(11), 2399-2404.
LI J S, WANG X Z, GAO X B. RCS Measurement of Small Size Target in Large Microwave Anechoic Chamber [J]. Fire Control Radar Technology, 2015, 44(3):72-75.
MENG D L, WU F, WANG W L. Uncertainty Evaluation of NIM Spherical Near-field Antenna Calibration Facility [J]. Acta Metrologica Sinica, 2017, 38(6): 758-762.
WU B, YANG W, TANG P, et al. Uncertainty Calibration of Antenna Spherical Near Field Test System[J]. Communication and Information Procession, 2020, 39(7):70-74.
CHENG X H, KANG S F, CAO Z Q. Design and Analysis of Antenna Specifications in Atmospheric Microwave Radiometers [J]. Radio Engineering, 2015, 45(10): 52-54.
GORDON J. Robotic Antenna Measurements, Reviews of Electromagnetics [online] https://tsapps. nist. gov/publication/get_pdf. cfm?pub_id=936351 (2023-12-25).
[1]
CAMPS CARMONA A J. Application of interferometric radiometry to Earth observation[D]. Barcelona: Universitat Politècnica de Catalunya, Spain, 1996.
[8]
FOGED L, RODRIGUEZ V, FORDHAM J, et al. Review of IEEE Std. 1720-2012: “Recommended Practice for Near-Field Antenna Measurements” [C]//IEEE Conference on Antenna Measurements & Applications. 2018.
YANG X Y,SUN J Y,CUI J H, et al. Effect of random errors of planar near-field measurement with ultra-low sidelobe antennas on antenna far-field pattern [J]. Joumal Harbin Engineering Uni, 2004, 25(2) 200-203.
[13]
CHEN Z. Sampling Effect on Radiation Characteristics of Automotive 5G Antenna in Spherical-Near-Field Test Range [C]//2021 15th European Conference on Antennas and Propagation (EuCAP).2021.
SANCHEZ-RAMA B, RIO V S D, LOPEZ R N, et al. Effects of the Antenna Measurement Uncertainties on the Estimation of the Differential Reflectivity [C]//2020 14th European Conference on Antennas and Propagation (EuCAP). 2020.
[18]
ASGHAR M E, WOLLENSCHLGER F, BORNKESSEL C, et al. Comparative Analysis of Spherical Near-Field Automotive Antenna Measurement Facilities[C]//2019 13th European Conference on Antennas and Propagation (EuCAP). 2019.
[20]
PREZ J R, BASTERRECHEA J. A Theoretical Comparison Between Three Plannar Near to Far-field Transformation Methods for Antenna Measurements [R].Engineering Physics, 2002.
KO E H, BELGIOVANE D J. Radiation and Scattering Pattern Characteristics of Chamfered-Tip Open-Ended Rectangular Waveguide Probes for Planar Near-Field Antenna Measurement Applications [C]//2021 Antenna Measurement Techniques Association Symposium (AMTA). 2021.
[21]
HOLLIS J S, LYON T J, CLAYTON L. Calculated radiation patterns of a paraboloid antenna for different distances from the antenna [C]//Microwave Antenna Measurements. Scientific-Atlanta. 1970.
[4]
IEEE Recommended Practice for Near-Field Antenna Measurements: IEEE Std 1720TM-2012.[S]. 2012.
MUNTIANU P I, BREINBJERG O.Comparison of Planar and Spherical Near-Field Antenna Measurements for a 60 GHz Dual-Polarized Probe and 60 GHz Offset Reflector Antenna[C]//2019 13th European Conference on Antennas and Propagation (EuCAP). 2019.
LIU X X, CHENG X Y, HUANG C Z. Antenna Planar Near-field Measurement System with Frequency 110GHz~170GHz [J]. Journal of Astronautic Metrology and Measurement, 2022, 42(5): 13-16.
[17]
BREINBJERG O, CASTANER M S. Antenna Measurement Challenges and Opportunities[R].Reviews of Electromagnetics II, 2023: 49.