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Antenna characterization is usually performed by antenna pattern measurements in an anechoic chamber. Subsequently, a conducted test, the Radiated Two-Stage (RTS) or the Wireless-Cable method can be used for an overall system test considering the measured patterns. In this paper we present a method to perform device tests for antenna arrays / smart antennas without the need of radiation pattern measurements,...
Two OTA test methods from literature are selected as those most suited for testing future 5G equipment when assessing end-to-end performance: coherent wave-field synthesis and radiated two-stage or “Wireless Cable”. Both methods have their advantages and disadvantages. Wave-field synthesis is transparent for antenna characteristics of Equipment-under-Test but not viable for large test objects. The...
In this paper, we describe the principle, hardware/software setup, calibration and verification measurement results of a wave field synthesis (WFS) over-the-air (OTA) testbed for global navigation satellite systems (GNSS). It represents a new approach that, in contrast to conventionally conducted and open-field tests, realistically emulates real world scenarios under controllable and repeatable conditions...
With the development of advanced communication systems such as ITS-G5 (C2C, C2I), mobile, and in-car communication systems, more and more systems are operating simultaneously. To verify their reliability in a coexistence scenario, all systems have to be tested under realistic conditions.
In satellite-based systems, such as global navigation satellite systems (GNSS), the use of antenna arrays is becoming increasingly common, as it allows various applications, such as jammer/spoofer suppression or improving the positioning accuracy in multipath-environments. Testing such equipment under realistic and reproducible conditions is often not feasible, for example in the case of a not fully...
For three-dimensional electromagnetic wave field synthesis, the orientation of dual-polarised antenna elements has influence on the size or volume of the usable ”quiet zone” or ”sweet spot”. The customary choice of polarisation directions along phi and theta allows for the full angular range over which wave fields can be synthesised. But, we show that this choice effectively reduces the number of...
For the sake of new radio devices to conform to respective standards, implementing functionality such as cognitive radio, Long Term Evolution beyond 2×2, or Global Navigation Satellite Systems, a demand for extensive testing arises. A promising solution is the validation inside an Over-the-Air testbed that creates a virtual electromagnetic environment using wave-field synthesis. This paper analyzes...
The ubiquitous problem of radio spectrum scarcity caused by ever-increasing traffic, e.g. in mobile communications, demands measures. One approach would be secondary use of spectrum by radio devices with cognitive abilities employing dynamic spectrum access. In order to avoid interference with the primary use of the spectrum, such cognitive devices must be thoroughly tested. In this paper, we present...
Due to increased demand and deployment of new technologies, such as electric vehicles, utilities face increasing fault currents in their systems. As a consequence protection devices must have higher ratings. Replacing existing infrastructure can prove expensive and complicated. Fault current limiters promise an upgrade solution that will mitigate the need for replacing existing breakers to keep fault...
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