Abstract
Plane Wave Generator (PWG) has recently attracted great attention from industry and academia for over-the-air (OTA) testing of base station (BS) antennas in the fifth-generation (5G) wireless communication systems. This paper aims to reduce the scattering from the PWG to the antenna under test (AUT), which might be problematic in the near-field OTA testing. First, we introduce a low monostatic radar cross section (RCS) PWG array element design. The PWG is also loaded with pyramidal microwave absorbing material (MAM) to suppress the multi-reflections between the AUT and the PWG. Furthermore, unlike coplanar PWG design generally reported in the literature, a novel non-coplanar design is proposed to realize the destructive interference of the scattered signals from the PWG, thereby significantly reducing the multiple reflections. PWG elements in the non-coplanar design are placed in the propagation direction according to planar and non-planar field distribution on the PWG radiated from the BS AUT. To validate our proposed design, a $4\times 4$ PWG array with a 108 mm element spacing and a non-coplanar structure is developed and experimentally validated. The measured results show that the second incident wave of the proposed non-coplanar PWG array structure based on non-planar field distribution is 7.9 dB lower than that of the classical coplanar PWG design from 2.3 GHz to 3.8 GHz, and 1.9 dB lower than that of the proposed non-coplanar PWG array structure based on planar field distribution, which demonstrates the effectiveness and robustness of our proposed design.
Highlights
MASSIVE multiple-input multiple-output (MIMO) is one of the key technologies employed at the base stations (BSs) in the sub-6 GHz 5G wireless communication systems [1], [2]
Inspired by the chessboard structure reported in the literature, a novel non-coplanar plane-wave generator (PWG) design is proposed in the paper to achieve destructive interference
A compact and low-scattering probe antenna is designed for the PWG element, with radar cross section (RCS) in the gazing direction less than -27.5 dBsm from 2.3 GHz to 3.8 GHz
Summary
MASSIVE multiple-input multiple-output (MIMO) is one of the key technologies employed at the base stations (BSs) in the sub-6 GHz 5G wireless communication systems [1], [2]. This issue is largely overlooked in the PWG design in the literature. Scattering reduction has been a long-standing research topic in the literature in the near-field measurement systems, where various techniques, e.g. data post-processing, downsizing the cross-section of probe antenna, and diverting the direction of the reflected wave, have been reported. Inspired by the chessboard structure reported in the literature, a novel non-coplanar PWG design is proposed in the paper to achieve destructive interference. Several scattering reduction strategies are employed in the PWG design, i.e. low scattering probe antenna design, PWG ground plane covered with absorbing material, and a novel non-coplanar PWG layout based on field distribution.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
