Echo Suppression by Spatial-Filtering Techniques in Advanced Planar and Spherical Near-Field Antenna Measurements [AMTA Corner]

Foged, L. J.; Scialacqua, L.; Mioc, F.; Saccardi, F.; Iversen, P. O.; Shmidov, L.; Braun, R.; Quijano, J. L. Araque; Vecchi, G.

doi:10.1109/map.2013.6735525

Cited by 16 publications

(15 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In near-field (NF) antenna measurement scenarios different echo reduction techniques [1][2][3][4][5][6] could be applied to enhance the accuracy of measurements, performed at lower frequencies and/or in outdoor environments as well as to reduce the impact of towers and supporting structures.…”

Section: Introductionmentioning

confidence: 99%

“…A very interesting echo reduction technique is based on the socalled spatial or modal filtering. Such technique projects the measured field over a set of orthogonal and complete set of basis functions [1,2,7,8] and applies a filtering on the order of basis function defined according to the AUT physical dimensions [1,2]. In [5,6], it has been shown that, when the measurement is performed rotating the AUT and keeping the probe fixed, the effectiveness of the spatial/modal filtering can be sensibly improved locating the AUT in an offset position with respect to the centre of rotation.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Application of the TSWE algorithm to echo reduction of under‐sampled offset spherical near‐field measurements

Saccardi

Mioc

Iversen³

et al. 2018

IET Microwaves, Antennas & Propagation

View full text Add to dashboard Cite

In spherical near‐field (NF) measurements, post‐processing techniques based on spatial filtering have been presented as an interesting tool for the mitigation of echoes or stray signals deriving from the environment surrounding the antenna under test (AUT). The spatial filtering is very efficient in measurement scenarios with a stationary AUT. Whenever the AUT is rotating, in order to increase the effectiveness of the echo reduction, the antenna needs to be displaced outside the centre of rotation. Unfortunately, the number of acquisition samples needed to represent the AUT in offset configuration is higher with respect to one needed for the onset configuration. An innovative NF/far‐field transformation algorithm for spherical offset measurements which allows to significantly reduce the number of measurement samples has been recently proposed. Such technique has been named translated spherical wave expansion (TSWE) and is based on the definition of new reference systems centred on the AUT rather than on the origin of the measurement sphere. In this study, the authors present the experimental investigation of the TSWE echo reduction properties for offset AUT.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Application of the TSWE algorithm to echo reduction of under‐sampled offset spherical near‐field measurements

Saccardi

Mioc

Iversen³

et al. 2018

IET Microwaves, Antennas & Propagation

View full text Add to dashboard Cite

show abstract

“…As is well-known, the measurement of antenna radiation pattern at low frequency cannot be accurately performed in anechoic chambers because of their small size in terms of wavelength and poor absorption performance of their walls, and the multipath signal from the side wall and floor may influence measurement accuracy [3]. To remove the multipath signal of environment, many approaches are utilized [4–9]. The propagation of multipath signal has normally time lag compared with the antenna radiation signal, the separation of multipath signal with a time gating is an effective method [10].…”

Section: Introductionmentioning

confidence: 99%

Clutter removal for measuring low-frequency narrow-band antenna using spectral estimation

2018

Int. J. Microw. Wireless Technol.

View full text Add to dashboard Cite

The measurement accuracy of low-frequency narrow-band antenna is heavily influenced by its environment, which is also difficult to remove the clutter with a time gating. This paper proposes a method to improve the measurement accuracy of low-frequency narrow-band antenna using signal processing technique. The method is to predict the unknown value out of received original signal with an auto-regressive model (AR model) based on modern spectral estimation theory, and the parameters in AR model are calculated by maximum entropy spectral estimation algorithm. Thus, a wideband signal compared with the original band is obtained, and then the time-domain resolution is enhanced. The time gating is more exactly to separate the antenna radiation signal from multipath signals. The simulation and experimental results show that about 50% extended data for each ends of original band can be obtained after spectral extrapolation, and the time-domain resolution after extrapolation is twice than the original narrow-band signal, and the influence of measurement environment can be eliminated effectively. The method can be used to improve accuracy in actual antenna measurement.

show abstract

“…Methods such as time domain characterization, frequency decomposition, and compensation techniques have been employed and studied [1][2][3][4][5][6][7][8]. Other techniques consist in spatial filtering or diagnostic techniques [9][10][11][12][13][14][15][16][17][18]. Last but not least, time-gating techniques are employed to remove reflected contributions.…”

Section: Introductionmentioning

confidence: 99%

Analysis of time filtering techniques for echo reduction in antenna measurements

González-Blanco

Silva

2017

Int. J. Microw. Wireless Technol.

View full text Add to dashboard Cite

This paper presents a review of filtering methods to eliminate echo in antenna measurements. Two different methods, fast Fourier transform and Matrix Pencil, are explained, compared, and simulated in a planar near field where other effects, such as aliasing, can and will be present if the simulation is not appropriately made and the parameters are not carefully chosen. Finally both methods are applied to real measurements of a dipole in a Microwave Vision Group multiprobe system and of a horn in a single-cut measurement. Other effects, such as window shift, may appear depending on the geometry of the system where the measurement is taken. These effects must be taken into consideration and carefully corrected.

show abstract

Echo Suppression by Spatial-Filtering Techniques in Advanced Planar and Spherical Near-Field Antenna Measurements [AMTA Corner]

Cited by 16 publications

References 6 publications

Application of the TSWE algorithm to echo reduction of under‐sampled offset spherical near‐field measurements

Application of the TSWE algorithm to echo reduction of under‐sampled offset spherical near‐field measurements

Clutter removal for measuring low-frequency narrow-band antenna using spectral estimation

Analysis of time filtering techniques for echo reduction in antenna measurements

Contact Info

Product

Resources

About