| 1. |
- Glazunov, Andres Alayon, 1969, et al.
(författare)
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Emulating Rician distributed channels in a hybrid chamber for OTA measurements
- 2021
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Ingår i: 2020 International Symposium on Antennas and Propagation, ISAP 2020. ; , s. 549-550
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Konferensbidrag (refereegranskat)abstract
- It has been shown by means of simulations that the rich isotropic multipath and the random line-of-sight channels and other Rician channels in-between can be successfully generated in the same over-the-air hybrid measurement chamber without the use of additional static or moving scatterers.
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| 2. |
- Glazunov, Andres Alayon, 1969, et al.
(författare)
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Multipath Rician Channel Simulation in the Test Zone of a Hybrid OTA Chamber
- 2021
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Ingår i: 15th European Conference on Antennas and Propagation, EuCAP 2021.
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Konferensbidrag (refereegranskat)abstract
- Multipath fields with ascribed Rician distribution parameters have been simulated in a novel hybrid chamber for over the air characterization of antenna systems and wireless devices. Simulations are based on waveguide mode summations representing a combination of the half-space rich isotropic multipath component and the on-axis line-of-sight component. It has been shown that the Rician distributed channels can be emulated without the use of additional static or moving scatterers.
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| 3. |
- Iupikov, Oleg, 1983, et al.
(författare)
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Hybrid OTA Chamber for Multi-Directional Testing of Wireless Devices: Plane Wave Spectrum Generator Design and Experimental Demonstration
- 2022
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Ingår i: IEEE Transactions on Antennas and Propagation. - 0018-926X .- 1558-2221. ; 70:11, s. 10974-10987
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Tidskriftsartikel (refereegranskat)abstract
- This paper investigates practical implementation aspects of a novel hybrid chamber concept that has been recently introduced for over-the-air testing of wireless devices. The chamber allows to synthesize a spectrum of plane waves (PWs) incident on a device under test from a wide range of angles-of-arrival (AoAs) through exploiting multiple field scattering inside the overmoded waveguide chamber. An optimal design approach for the plane wave spectrum generator (PWSG) array inside the chamber is presented considering: (i) array antenna impedance matching for the desired test zone (TZ) quality and AoAs range; (ii) an operational frequency bandwidth of the test environment and an instantaneous signal bandwidth; and (iii) the impact of the PWSG excitation errors. A robust linearly constrained minimum variance (LCMV) beamformer is formulated to realize the desired test environment over a wide frequency band, while accounting for the varying number of the waveguide propagating modes as excited by the PWSG array. Numerical simulations and measurements with the first prototype of the hybrid chamber for FR1 frequency band (~3.5 GHz) are presented. This prototype includes a 7 × 7 bowtie antenna element PWSG array, a 1.00 × 1.25 × 1.75 m metal waveguide chamber, an off-line optimal array beamforming setup, and a planar scanner for the TZ characterization.
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| 4. |
- Iupikov, Oleg, 1983, et al.
(författare)
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Reconfigurable Intelligent Surfaces for OTA Testing: Optimization and Initial Results
- 2023
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Ingår i: IEEE Conference on Antenna Measurements and Applications, CAMA. - 2474-1760. ; , s. 846-851
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Konferensbidrag (refereegranskat)abstract
- We discuss a new application of RIS for Over-The-Air (OTA) testing of antenna systems and wireless devices, particularly as a cost-effective alternative to millimeter-wave phased-array plane wave generators (PWGs). We present a general approach for the fast modeling and design of the RIS-based PWG. This includes an optimal beamforming algorithm for a RIS and a strategy for configuring the RIS unit cells (UCs) to emulate far-field conditions in the test zone (TZ) with a controllable angle of arrival (AoA) of the incoming plane wave. The proposed approach has been used to derive requirements for a UC of the 21x21 element RIS-based PWG. Our preliminary numerical results demonstrate that the RIS-based PWG allows for synthesizing a TZ with a high-quality plane wave spectrum, where the peak-to-peak variation in field magnitude remains below 0.7 dB, while phase fluctuations do not exceed 5 deg within the range of AoA from -7 deg to 7 deg.
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| 5. |
- Iupikov, Oleg, 1983, et al.
(författare)
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The Hybrid Chamber for OTA measurements: Plane Wave Spectrum Quality Vs. Dynamic Range Trade-off
- 2022
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Ingår i: 2022 16th European Conference on Antennas and Propagation, EuCAP 2022.
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Konferensbidrag (refereegranskat)abstract
- In this paper, the trade-off between the quality of the plane wave spectrum synthesized in the test zone of the hybrid over-the-air (OTA) chamber and factors affecting the dynamic range of this measurement system is investigated. The hybrid chamber performance is compared to a plane wave generator (PWG) in free space. The performance evaluation is focused on the field radiated into the test zone (TZ) while maintaining its quality according to 3GPP specification. It is demonstrated that a good quality can be achieved for the synthesized plane wave spectrum.
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| 6. |
- Krasov, Pavlo, 1981, et al.
(författare)
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Characterization and Calibration of the Hybrid OTA Chamber Using a Field Scanner
- 2022
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Ingår i: 2022 16th European Conference on Antennas and Propagation, EuCAP 2022.
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Konferensbidrag (refereegranskat)abstract
- This paper investigates the characterization and calibration procedure of the hybrid over-the-air (OTA) measurement chamber. We present a prototype of the hybrid chamber and analyze its capabilities to generate a plane wave spectrum in practice. A planar field scanner is used to acquire the embedded element fields of the chamber array for test zone (TZ) synthesis in post-processing. The repeatability of the field acquisition is evaluated. It is shown that the synthesized TZ meets the 3GPP specifications for TZ field variations for plane wave generators (PWG) in the presence of acquisition imperfections.
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| 7. |
- Krasov, Pavlo, 1981, et al.
(författare)
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Optimization of the TRP evaluation in Anechoic-Reverberation Hybrid Chamber
- 2024
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Ingår i: 18th European Conference on Antennas and Propagation, EuCAP 2024.
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Konferensbidrag (refereegranskat)abstract
- A hybrid, reconfigurable anechoic-reverberation antenna measurement chamber has recently been introduced. The chamber is developed for fast characterization of the active antenna radiated power and directive characteristics in a single measurement environment. In the present work, we propose optimizations of the hybrid chamber design in the configuration that uses E-field scanner. Introducing the wedge reflector in the chamber allows for a reduction in the total number of acquisition samples four times compared to λ/2 spaced scan during the total radiated power (TRP) measurements.
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| 8. |
- Krasov, Pavlo, 1981, et al.
(författare)
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Quiet Zone Quality of a Plane Wave Generator inside an Over-Moded Waveguide Chamber Emulating a Variable Angle of Incidence
- 2021
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Ingår i: 15th European Conference on Antennas and Propagation, EuCAP 2021.
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Konferensbidrag (refereegranskat)abstract
- We investigate the use of a hybrid over-the-air (OTA) measurement chamber to emulate far-field testing conditions. The focus has been on the generation of a plane wave arriving at an arbitrary angle-of-arrival (AoA) to the device-under-test (DUT) without mechanical steering. The chamber consists of an oversized waveguide (WG) and a planar array antenna with adaptive beamforming. A modified linear constrained minimum variance (LCMV) beamforming algorithm is used to form a quiet zone (QZ) in the DUT region by using the reflections from the WG's metal walls. The LCMV beamformer formulation has been extended to achieve a volumetric QZ with the desired amplitude and phase uniformity. Numerical studies for the QZ size corresponding to an FR1 base station demonstrate promising results with the low levels of amplitude and phase variation. The AoA coverage of this chamber meets 3GPP specification requirements for OTA conformance testing of base stations with active antenna systems.
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| 9. |
- Krasov, Pavlo, 1981, et al.
(författare)
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Reconfiguration Capabilities of the Anechoic-Reverberation Hybrid Chamber for TRP Measurements of Active Antenna Systems
- 2023
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Ingår i: 17th European Conference on Antennas and Propagation, EuCAP 2023.
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Konferensbidrag (refereegranskat)abstract
- A hybrid, reconfigurable anechoic-reverberation antenna measurement chamber was recently introduced with the vision to enable fast characterization of the active antenna radiated power and directive characteristics in a single measurement environment. The initial studies included its design and analysis in the plane wave spectrum generator scenario. In the present work, we investigate chamber reconfiguration capabilities for performing total radiated power (TRP) measurements. We show how different types of interchangeable hybrid chamber modules allow realizing several possible ways of measuring TRP. Trade-offs in terms of measurement time and implementation complexity are discussed. Finally, one of the methods, using a chamber array antenna module, is selected and demonstrated in simulations. Our initial results indicate TRP measurement error within ±0.5 dB.
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| 10. |
- Kruglov, Dmitrii, 1994, et al.
(författare)
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Contactless Measurement of a D-Band On-Chip Antenna Using an Integrated Reflective Load Switch
- 2024
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Ingår i: IEEE Antennas and Wireless Propagation Letters. - 1548-5757 .- 1536-1225. ; 23:3, s. 1075-1079
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Tidskriftsartikel (refereegranskat)abstract
- A novel measurement setup is proposed for the contactless characterization of on-chip antennas. A D-band patch antenna is fabricated on a 100 μm-thick GaAs substrate and is monolithically integrated with a reflective load switch to allow for fast electronic control of the antenna port termination. The antenna under test is illuminated by a reference antenna in the anechoic chamber after which the impedance and gain of the patch antenna are reconstructed from the change in backscattered field due to different port terminations. In our experiment, the over-the-air reconstructed antenna input impedance exhibits a frequency shift of less than 1% with respect to the (non-ideal) on-wafer probe measurement in the 115–130 GHz frequency range. Furthermore, the measured realized gain of 0.9±0.5 dBi is close to the simulated one of 1.1 dBi.
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