A Review of Antennas and Propagation for MIMO Wireless Communications

Abstract-The geometrical parameters of antenna arrays in a multiple-input multiple-output (MIMO) link that will maximize the ergodic channel capacity of the system are investigated. The problem of selecting the optimum number of the elements at the base station antenna array is also included. The genetic algorithm technique is applied for the optimisation process, using the ergodic capacity as a fitness function. A discrete model based on statistical distribution of the Angle of Arrival (AoA) of the incoming rays is considered. Searching for more compactness in the antenna size and higher system capacity, different array configurations with non-uniform inter-element spacing are considered, such as linear array, circular array and multicircular array (Star) geometries. Numerical examples that illustrate new designs of non-uniform spaced arrays are presented to show the capability of the developed procedures to optimize the capacity of indoor MIMO systems.

Section: Introductionmentioning

confidence: 99%

Optimization of Channel Capacity for Indoor Mimo Systems Using Genetic Algorithm

Mangoud¹

2009

“…As the measurements were performed in time varying environment, 20 measurements were performed for each case by slightly changing the position of either transmitter or receiver. The normalized channel matrix H is obtained using procedure given in [13]. …”

Section: Measurement Scenariomentioning

confidence: 99%

Characterization of Reconfigurable Mimo Antennas for Channel Capacity in an Indoor Environment

Hussain¹,

Khan²,

Abu-Al-Saud³

et al. 2016

Abstract-In this paper, three different frequency reconfigurable multiple-input-multiple output (MIMO) antennas are characterized in terms of their channel capacity performance in an indoor environment. Two 2 × 2 and one 4 × 4 MIMO antenna configurations are investigated. A complete MIMO system is implemented using software defined radio (SDR) platform. The antenna under test can be used at either transmitter or receiver ends. The channel capacity of the system is evaluated by computing the channel coefficient matrix. The measurements are performed at 2.45 GHz for line of sight (LOS) and non-line of sight (NLOS) scenarios. A comparison of the antennas is performed with an ideal system scenario with totally uncorrelated channels as well as an array of standard monopoles which are half-wavelength apart. The effects of antenna element efficiencies, radiation patterns and spacings on the channel capacity are discussed.

“…MIMO communication system achieves enhancement in the data rate in multipath signal propagation. The MIMO technology used in UWB will provide an increase in channel capacity over that used in a narrowband system [22]. UWB MIMO system behaviour is considered in [23][24][25].…”

Section: Introductionmentioning

confidence: 99%

Triple Band Notched Dg-Cebg Structure Based Uwb Mimo/Diversity Antenna

Jaglan¹,

Gupta²,

Kanaujia³

et al. 2018

Abstract-A MIMO/Diversity antenna with triple notch characteristics is proposed in this article. The proposed antenna has triple notches in the WiMAX band (3.3-3.6 GHz), WLAN band (5-6 GHz), and X-band satellite communication (7.2-8.4 GHz) band. Defected Ground Compact Electromagnetic Band Gap (DG-CEBG) is a design used to accomplish band notches. Defected ground planes are utilised so as to achieve compactness in conventional EBG structures. The proposed WiMAX band, WLAN band, and X-band satellite communication band DG-CEBG structures show a compactness of around 46%, 50%, and 48%, respectively, over a conventional EBG structure. In these structures, decoupling strips and a slotted ground plane are used to enhance the isolation between two closely spaced UWB monopoles. The individual monopoles are 90 • angularly separated with a stepped structure which helps to reduce mutual coupling and also contributes towards impedance matching by increasing the current path length. |S 21 | or mutual coupling is found to be less than 15 dB over the whole UWB frequency range. The Envelope Correlation Coefficient (≤ 0.5) is within the acceptable limits over the whole UWB frequency range. Notched frequency depends on the parameters of DG-CEBG structures; when there is a change in these parameters notch frequency is also changed. A low cost FR-4 substrate with thickness (h) = 1.6 mm, permittivity (ε) = 4.4 and loss tangent (δ) = 0.02 is used for the proposed antenna, and it has a compact size of 58 × 45 × 1.6 mm 3 .