Antenna Measurements at Millimeter and Submillimeter Wavelengths

12th European Conference on Antennas and Propagation (EuCAP 2018)

et al. 2018

Section: Instrumentationmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Antenna Measurements at Millimeter Wavelengths - Overview

Räisänen¹,

Zheng²,

12th European Conference on Antennas and Propagation (EuCAP 2018)

et al. 2018

“…Another option is to create a plane reference wave by means of a shaped plane mirror which is employed as the collimator in compact antenna ranges [37]. Nevertheless, correctly shaping the mirror for high frequency indirect holography requires accurate and expensive machining.…”

Section: Indirect Off-axis Holographymentioning

confidence: 99%

Indirect Off-Axis Holography for Antenna Metrology

Arboleya

Laviada

Holographic Materials and Optical Systems

et al. 2017

Self Cite

Phase acquisition in antenna measurement, especially at millimeter-and submillimeterwave frequencies, is an expensive and challenging task. The need of a steady phase reference demands not only a very stable source but unvarying temperature conditions and strong positioning accuracy requirements. Indirect off-axis holography is an interferometric technique that allows for characterization of an unknown field by means of a simple filtering process of the hologram or intensity interference pattern in the spectral domain, provided that the reference field, employed to interfere with the unknown field, is known in amplitude and phase. This technique can be used to avoid the effect of the errors related to the phase acquisition and to further develop new efficient and robust techniques capable of phase retrieval from amplitude-only acquisitions allowing for cost and complexity reduction of the measurement setup. A short review of the state-of-theart in antenna metrology is presented in this chapter, as well as a description of conventional indirect off-axis techniques applied to this field. Last sections are devoted to the description of novel measurement techniques developed by the authors in order to overcome the main limitations of the conventional methods.

“…Furthermore, errors due to cable flexing [9] or the accuracy of the positioners [10] become more relevant at higher frequencies.…”

mentioning

confidence: 99%

Phaseless Characterization of Broadband Antennas

Arboleya¹,

Laviada²,

IEEE Trans. Antennas Propagat.

et al. 2016

Self Cite

Abstract-A new efficient method for broadband antenna characterization from phaseless acquisitions in the frequencydomain is presented. The phase-retrieval technique is based on an extrapolation of the off-axis indirect holography. In common with the conventional approach, the power of the interferometric field of the antenna under test and a reference antenna, whose field is known in advance, as well as the power of the antenna under test alone, is measured at the desired frequencies. Nevertheless, the phase retrieval is accomplished independently at each spatial point by filtering in the time-domain rather than in the k-space. Thus, the dependency of the phase retrieval on the position accuracy is reduced and it can be accomplished simultaneously at all frequencies without resorting to iterative schemes. Moreover, it yields a less dense sampling and a phase retrieval algorithm not dependent on the geometry of the acquisition. The method is illustrated with a numerical example in the W -band as well as with two near-field measurement examples in the Ka-and W -bands.