Mutual Coupling Suppression With Decoupling Ground for Massive MIMO Antenna Arrays

Multiple Input Multiple Output (MIMO) and massive MIMO technologies play a significant role in mitigating five generation (5G) channel propagation impairments. These impairments increase as frequency increases, and they become worse at millimeter-waves (mmWaves). They include difficulties of material penetration, Line-of-Sight (LoS) inflexibility, small cell coverage, weather circumstances, etc. This paper simulates the 5G channel at the E-band frequency using the Monte Carlo approach-based NYUSIM tool. The urban microcell (UMi) is the communication environment of this simulation. Both MIMO and massive MIMO use uniformly spaced rectangular antenna arrays (URA). This study investigates the effects of MIMO and massive MIMO on LOS and Non-LOS (NLOS) environments. The simulations considered directional and omnidirectional antennas, the Power Delay Profile (PDP), Root Mean Square (RMS) delay spread, and small-scale PDP for both LOS and NLOS environments. As expected, the wide variety of the results showed that the massive MIMO antenna outperforms the MIMO antenna, especially in terms of the signal power received at the end-user and for longer path lengths.

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OTA Testing for Massive MIMO Devices Using Cascaded APM Networks and Channel Emulators

International Journal of Antennas and Propagation ◽

10.1155/2019/6901383 ◽

2019 ◽

Vol 2019 ◽

pp. 1-14

Author(s):

Lijian Xin ◽

Yong Li ◽

Hao Sun ◽

Xiang Zhang

Keyword(s):

Antenna Arrays ◽

Massive Mimo ◽

Structural Model ◽

Radio Channel ◽

Multiple Input Multiple Output ◽

Angular Spectrum ◽

Anechoic Chamber ◽

Mimo Antenna ◽

Channel Emulator ◽

Input Multiple Output

This paper proposes an over-the-air (OTA) testing setup for millimeter-wave (mmWave) massive multiple-input multiple-output (MIMO) equipment using cascaded amplitude and phase modulation (APM) network and channel emulator. Compared with the existing test setup with mechanical switch, the proposed testing setup enables more accurate reconstruction of the radio channel environment under the multiprobe anechoic chamber (MPAC) setup without increasing the number of channel emulators (CEs) to control the system cost. The constructed MPAC testing setup for mmWave and massive MIMO equipment is composed of an anechoic chamber, a sectored probe wall containing a number of probes, an APM network, a fading channel emulator, and a user emulator (UE). In this paper, the structural model and the performance advantages of the proposed radiated testing setup are described, and a fully connected APM network for radiated testing is more prominent than the existing switch. Moreover, the angular spectrum is selected as the performance metric for the reconstructed channel. The ability of the proposed system to reconstruct the power angular spectrum (PAS) of the target channel is studied under both static and dynamic channel models, which can reflect the performance of beamforming procedures of the massive MIMO antenna arrays, e.g., beam acquisition, tracking, and refinement. The simulation results for angular spectrum support the superiority of the proposed OTA testing setup. Furthermore, the simulations for average channel capacity also show that radiated testing setup using cascaded APM network and channel emulator is valid.

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Mutual coupling reduction in dielectric resonator MIMO antenna arrays using metasurface orthogonalize wall

2017 11th European Conference on Antennas and Propagation (EUCAP) ◽

10.23919/eucap.2017.7928602 ◽

2017 ◽

Cited By ~ 3

Author(s):

Mohammadmahdi Farahani ◽

M. Akbari ◽

Mourad Nedil ◽

Tayeb A. Denidni

Keyword(s):

Antenna Arrays ◽

Dielectric Resonator ◽

Mutual Coupling ◽

Mimo Antenna ◽

Mutual Coupling Reduction

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Slotted E-Shaped Meta-Material Decoupling Slab for Densely Packed MIMO Antenna Arrays

Micromachines ◽

10.3390/mi12080873 ◽

2021 ◽

Vol 12 (8) ◽

pp. 873

Author(s):

Karim H. Moussa ◽

Ahmed S. I. Amar ◽

Mohamed Mabrouk ◽

Heba G. Mohamed

Keyword(s):

Antenna Arrays ◽

Communication Systems ◽

Mutual Coupling ◽

Spatial Diversity ◽

Center Frequency ◽

Wireless Communication Systems ◽

Mimo Antenna ◽

Microstrip Patch ◽

Multiple Input ◽

Array Gain

In contemporary wireless communication systems, the multiple-input and multiple-output systems are extensively utilized due to their enhanced spectral efficiency and diversity. Densely packed antenna arrays play an important role in such systems to enhance their spatial diversity, array gain, and beam scanning capabilities. In this article, a slotted meta-material decoupling slab (S-MTM-DS) with dual reflexes slotted E-shapes and an inductive stub is proposed. Its function was validated when located between two microstrip patch antenna elements to reduce the inter-element spacing, the mutual coupling, the return losses, and manufacturing costs due to size reduction. A prototype is simply fabricated in a volume of 67.41 × 33.49 × 1.6 mm3 and frequency-span measured from 8.4:11 GHz. At 9.4 GHz frequency, the spaces between the transmitting elements are decreased to 0.57 of the free space wavelength. When the proposed isolation S-MTM-DS is applied, the average isolation among them is measured to be −36 dB, the operational bandwidth is enhanced to be 1.512 GHz, the fractional bandwidth improved to be 16.04%, and the return losses are decreased to be −26.5 dB at 9.4 GHz center frequency. Consequently, the proposed design has the potential to be implemented simply in wireless contemporary communication schemes.

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