Impact of dielectric substrate on the performance of an 8 × 8 magneto-electric dipole phased array antenna for 5G mmWave applications

The impact of the substrate dielectric material on the performance of a wideband magneto-electric dipole (MED) phased array antenna is systematically studied in this article. Four commercially available dielectric substrates for mmWave applications, i.e., Rogers RO 5880, RO 3003, RO 4350B, and Panasonic Megtron-6, are considered in the design investigation of the proposed MED phased array antenna. First, the influence of the dielectric constant on the operating frequency of the unit cell MED antenna is explored in the broadside direction (θ = 0°). Second, the scanning impedance is assessed at various scanning angles for both E- and H-plane scanning. Finally, the radiation performance of the proposed design of a finite 8 × 8 MED phased array antenna is examined. This study gives a foundational understanding of the impact of dielectric characteristics on the performance of MED phased arrays. The analysis revealed that the MED phased array antenna based on substrates with a higher dielectric constant exhibited a smaller scanning angle than the substrate with a lower dielectric constant. The findings may serve as practical guidelines for selecting the dielectric substrates for the 5G mmWave phased array antenna in order to adapt their design to an application’s specifications

Stochastic Phased Array Performance Indicators for Quality-of-Service-Enhanced Massive MIMO

In this paper, we show that the signal-to-interference-plus-noise ratio (SINR) at a base station (BS) equipped with an arbitrary physical array antenna can be expressed as a function of two fundamental figures-of-merit (FoMs): (I) the instantaneous effective gain (IEG), and (II) the beamforming-channel correlation (BCC). These two FoMs are functions of the array antenna layout, the antenna elements, the propagation channel and the applied signal processing algorithms, and hence they are random variables (RVs) in general. We illustrate that both FoMs provide essential insights for quality-of-service (QoS)-based phased array design by investigating their statistics for BSs applying full-digital (FD) zero forcing (ZF) beamforming. We evaluate various array designs and show that arrays with higher IEGs and a reduced probability of low BCCs can increase the ergodic sum rate and reduce the need for scheduling

Impact of dielectric substrate on the performance of an 8 × 8 magneto-electric dipole phased array antenna for 5G mmWave applications

The impact of the substrate dielectric material on the performance of a wideband magneto-electric dipole (MED) phased array antenna is systematically studied in this article. Four commercially available dielectric substrates for mmWave applications, i.e., Rogers RO 5880, RO 3003, RO 4350B, and Panasonic Megtron-6, are considered in the design investigation of the proposed MED phased array antenna. First, the influence of the dielectric constant on the operating frequency of the unit cell MED antenna is explored in the broadside direction (theta = 0 degrees). Second, the scanning impedance is assessed at various scanning angles for both E- and H-plane scanning. Finally, the radiation performance of the proposed design of a finite 8 x 8 MED phased array antenna is examined. This study gives a foundational understanding of the impact of dielectric characteristics on the performance of MED phased arrays. The analysis revealed that the MED phased array antenna based on substrates with a higher dielectric constant exhibited a smaller scanning angle than the substrate with a lower dielectric constant. The findings may serve as practical guidelines for selecting the dielectric substrates for the 5G mmWave phased array antenna in order to adapt their design to an applications specifications.Funding Agencies|European Union [766231-WAVECOMBE-H2020-MSCA-ITN-2017]</p

Design of a Planar Eleven Antenna for Optimal MIMO Performance as a Wideband Micro Base-station Antenna

A new low-profile planar Eleven antenna is designed for optimal MIMO performance as a wideband MIMO antenna for micro base-stations in future wireless communication systems. The design objective has been to optimize both the reflection coefficient at the input port of the antenna and the 1-bitstream and 2-bitstream MIMO efficiency of the antenna at the same time, in both the Rich Isotropic MultiPath (RIMP) and Random Line-of-Sight (Random-LOS) environments. The planar Eleven antenna can be operated in 2-, 4-, and 8-port modes with slight modifications. The optimization is performed using genetic algorithms. The effects of polarization deficiencies and antenna total embedded efficiency on the MIMO performance of the antenna are further studied. A prototype of the antenna has been fabricated and the design has been verified by measurements against the simulations.Comment: 7 pages, 15 figures, 15 reference

Impact of Excitation and Weighting Errors on Performance of Compact OTA Testing Systems

This paper investigates the impact of complex excitation errors of the chamber array antenna on the accuracy of the test zone of a random line-of-sight over-the-air testing setup. First, several combinations of compact chamber arrays of lengths L and short distances D between the test zone and the chamber array, which emulate a plane wave impinging at the test zone are obtained. The chamber array is linear and uniform with 100 antenna elements, and a linear taper was applied to some of the elements to emulate a plane wave impinging at the test zone with more compact setups. A subset of L and D was chosen, providing compact over-the-air test setups that fulfilled the defined figures of merit, which assess the similarity of the obtained field distribution to that of a plane wave. The tolerance of the chosen setups to complex excitation errors of the chamber array was then investigated, concluding that these errors must be considered when defining appropriate L and D combinations. Moreover, the performance of the matched filter and zero-forcing algorithms is evaluated for errors of the device under test array weighting coefficients. A random line-of-sight over-the-air testing setup with two arrays was simulated, where one of the arrays emulated the desired signal and the other emulated the interference, observing that the errors were more significant at higher signal-to-noise ratios. Additionally, the zero-forcing algorithm was more sensitive to errors than the matched filter, which was expected since the accuracy of the former for interference suppression is critical.Comment: EuCAP2023 conferenc

Wireless Performance Evaluation of Building Layouts: Closed-Form Computation of Figures of Merit

This paper presents a part of our ground-breaking work on evaluation of buildings in terms of wireless friendliness in the building-design stage. The main goal is to devise construction practices that provide for a good performance of wireless networks deployed in buildings. In this paper, the interference gain (IG) and power gain (PG) are defined as two figures of merit (FoM) of the wireless performance of buildings. The FoMs bridge the gap between building design and wireless communications industries. An approach to derive exact closed-form equations for these FoMs is proposed for the first time. The derived analytic expressions facilitate straightforward and more computationally efficient numerical evaluation of the proposed FoMs as compared to Monte Carlo simulations for well-known indoor propagation models. It is shown that the derived closed-form expression can be readily employed to evaluate the impact of building properties, such as the sizes and the aspect ratios (ARs) of rooms, on the wireless performance. The proposed approach sheds light to architects on evaluation and design of wireless-friendly building layouts

Wireless Energy Efficiency Evaluation for Buildings Under Design Based on Analysis of Interference Gain

In this paper, we present part of our ground-breaking work that bridges building design and wireless network deployment. The original contributions lie in: i) defining interference gain (IG) as an intrinsic figure of merit (FoM) of a building &amp; x2019;s wireless performance in terms of interference signal blockage; ii) developing analytic models to calculate IG; and iii) developing a novel method to calculate the optimum transmitting power to achieve the maximum IG of a building. The IG is derived as an integral transform of the probability density function (PDF) of the distance from a probe user equipment (UE) with a random position relative to a wall, and with a uniformly distributed direction. Furthermore, the PDF of the random distance is derived in closed-form for rectangular rooms to facilitate fast computation of the IG of a building under design (BUD) tiled by rectangular rooms and corridors. For BUD with irregular rooms, a random shooting algorithm (RSA) is proposed to numerically compute the PDF. The closed-form expression and the RSA are compared and validated. Numerical results show the validity of both the model to calculate IG and the methodology to derive the optimum transmitting power to achieve the maximum IG of a given building. The results shed light to architects on how to design buildings with desirable wireless performance and for radio engineers on how densely wireless access points can be deployed to approach the intrinsic wireless performance of a building