Three-Element MIMO Antenna System With Pattern and Polarization Diversity for WLAN Applications

In this article, a dual sense dual port circularly polarized cylindrical dielectric resonator antenna (CDRA) is discussed for multiple input multiple output (MIMO) applications. Three exclusive features of the proposed radiator are (i) modified circule‐shaped aperture generates circular polarization for both the ports; (ii) proposed structure can generate left‐hand circular polarization (LHCP) and right‐hand circular polarization (RHCP) that depends on feed port selection; (iii) by introducing the concept of polarization diversity (LHCP/RHCP) and defected ground structure (DGS) between the two radiator, isolation is improved. A prototype of proposed radiator is fabricated and experimentally tested to authenticate the simulated results. The fractional impedance bandwidth for port 1 and port 2 is 15.1% and 14.9%, respectively. Within the targeted operating band, the isolation is better than −25 dB between the ports. Different diversity performance parameters are also calculated and they are also lie within their optimum limit. The proposed MIMO antenna is suitable for WLAN (5.5/5.8 GHz) applications.

{normalρ}_{normale} = \frac{{false| S_{11}^{*} S_{12} + S_{21}^{*} S_{22} false|}^{2}}{true(true(1 - true(false| S_{11}^{2} false| + false| S_{21}^{2} false| true) true) true(1 - true(false| S_{22}^{2} false| + false| S_{12}^{2} false| true) true) true)}

where, S ii and S ij represent the input reflection coefficient and isolation between the antenna elements respectively.…”

Section: Diversity Performancementioning

confidence: 99%

{normalρ}_{e, i j} = \frac{{false| \underset{4}{false\int} true \int_{π} true[{\overset{A}{true}}_{i} true(θ, ϕ true) * {\overset{A}{true}}_{j} true(θ, ϕ true) true] d ω false|}^{2}}{\underset{4}{false\int} true \int_{π} {false| {\overset{A}{true}}_{i} true(θ, ϕ true) false|}^{2} d ω \underset{4}{false\int} true \int_{π} {false| {\overset{A}{true}}_{j} true(θ, ϕ true) false|}^{2} d ω}

where

{\overset{A}{true}}_{i} true(θ, ϕ true)

and

{\overset{A}{true}}_{j} true(θ, ϕ true)

presents the 3‐D far‐field pattern function when port i and port j is excited, respectively. * represents the Hermitian product operator and ω presents the solid angle.…”

Section: Diversity Performancementioning

confidence: 99%

Dielectric resonator based circularly polarized MIMO antenna with polarization diversity

Das

Sharma

Gangwar

2018

“…One important parameter of MIMO antennas is the envelope correlation coefficient (ECC) which is the indicative of the diversity performance. Assuming uniform multipath environment, the ECC between i th and j th elements of an N ‐element MIMO antenna is calculated as follows:

{normalρ}_{e} (i, j, N) = \frac{{false| \sum_{n = 1}^{N} S_{i, n}^{*} S_{n, j} false|}^{2}}{\prod_{k = i, j} true(1 - \sum_{n = 1}^{N} S_{k, n}^{*} S_{n, k} true) {normalη}_{k}}

where η k is the radiation efficiency of the k th element. The radiation efficiency of the proposed MIMO antenna is 70% at the resonance frequency, and the decrement of radiation efficiency degrades the diversity performance (see Equation ).…”

Section: Resultsmentioning

confidence: 99%

A compact four‐element MIMO antenna for WLAN applications

Pandit

Mohan

Ray

2018

This article presents a compact four‐element multiple‐input multiple‐output (MIMO) antenna for wireless local area network applications. The overall volume of the proposed MIMO antenna is 26 mm × 26 mm × 0.8 mm and the edge‐to‐edge distance is 4 mm. The MIMO antenna operates at 5.6 to 5.8 GHz frequency band with isolation greater than 15.4 dB. The envelope correlation coefficient and the channel capacity loss for the proposed MIMO antenna are within the acceptable limits in the operating frequency band. The simulated results are verified with fabrication and measurements.

“…Using the neutralization line technology, a dual‐element antenna with two printed monopoles has an isolation higher than 18 dB . By using pattern and polarization diversity, the three‐element MIMO antenna achieves good isolation higher than 15 dB . As presented in these references, meandering line resonator and polarization diversity all need larger space.…”

Section: Introductionmentioning

confidence: 99%

“…By using pattern and polarization diversity, the three‐element MIMO antenna achieves good isolation higher than 15 dB . As presented in these references, meandering line resonator and polarization diversity all need larger space. For the neutralization line, it may take a long time to find the favorable connection points, which are usually located at low‐impedance area.…”

Section: Introductionmentioning

confidence: 99%

Dual‐element antenna with high isolation operating at the WLAN bands

Shen

Zhang

Jiao

et al. 2019

This article proposes a dual‐element antenna working in the 2.4/5‐GHz WLAN bands with high isolation. The antenna element is a coupled‐fed structure, which is formed by a driven monopole and a shorting branch. The decoupling structure disposed between the elements is a hybrid structure, which includes a protruded ground for the 2.4‐GHz WLAN band and a narrow slot etched on the ground plane for the 5‐GHz WLAN band. Moreover, to reduce the dimension of the protruded ground, two 8.2‐nH lumped inductors are embedded in the branches. The measured −10 dB reflection coefficient bandwidths are in the range of 2400‐2497 MHz and 5150‐5940 MHz. The measured transmission coefficient indicates that a good isolation higher than 20 dB over the two bands is obtained.