Electronic engineering

Engineering

Telecommunications

Physics

Control engineering

Antenna factor

Decoupling (probability)

Stub (electronics)

Antenna measurement

MIMO

Beamforming

Optics

Antenna (radio)

Monopole antenna

Electrical engineering

Ground plane

Diversity gain

Micromachines

This paper presents a compact two-element MIMO antenna with improved isolation for triple-band applications. The antenna consists of two radiating elements with the shared ground plane and a novel decoupling structure. Each antenna element has three stubs with different lengths, which work as quarter-wavelength monopoles to give a triple-band operation. The decoupling system is made by etching various slots in an inverted H-shape stub attached to two quarter-circles at its lower ends. The simulated and measured results show that the antenna operates (|S11| < −10 dB) at the key frequency bands of 2.4 GHz (2.29−2.47 GHz), 3.5 GHz (3.34−3.73 GHz), and 5.5 GHz (4.57−6.75 GHz) with a stable gain and radiation patterns. Moreover, the MIMO antenna shows good isolation characteristics. The isolation is more than 20 dB, the envelope correlation coefficient is <0.003, and diversity gain is 9.98 dB, within the frequency band of interest. Furthermore, the MIMO antenna has a compact size of 48 mm × 31 mm × 1.6 mm. These features of the proposed antenna make it a suitable candidate for I.S.M., 5G sub-6 GHz, and WLAN applications.

A Compact MIMO Antenna with Improved Isolation for ISM, Sub-6 GHz, and WLAN Application