A Compact MIMO Antenna with Inverted C-Shaped Ground Branches for Mobile Terminals

Abstract

A compact printed MIMO antenna for mobile terminals is presented. With two planar antenna elements, the −6 dB impedance bandwidth of 2.32 GHz (1.48–3.8 GHz) is obtained, which covers GSM 1800/1900, UMTS, WLAN, Wimax, S-band, and most of LTE bands. Each antenna element with a small occupation of 15 × 20 mm2consists of a driven strip and a shorted strip. Two inverted C-shaped ground branches are introduced between two elements to improve the isolation. The simulated results are studied and the measured results show that high isolation of more than 18 dB at the entire operating band is achieved. Meanwhile, the impedance performance is also improved by adding the branches. Furthermore, the measured radiation performances and envelope correlation coefficient also demonstrate that the proposed antenna could be a good candidate for mobile terminals.

Flexible MIMO Antennas for 5G Applications

“…It increases data capacity & speed [11,12]. Currently, MIMO multiantenna research is focused on the development of high-performance, low-cost antenna layout concepts [13][14][15].The conformal antenna [16] can accomplish this goal. Conformal antennas may be constructed on the device's surface, which avoids damaging the carrier's mechanical structure and saves space [17][18][19].…”

Mutual Coupling Reduction Using a Protruded Ground Branch Structure in a Compact UWB Owl-Shaped MIMO Antenna

“…It means that, if the MIMO antenna elements were placed very close to each other, there would be a strong correlation between their signals and the utility of MIMO would be reduced, so the mutual coupling is inversely proportional to the separation between the antenna elements. Thus, it is a challenge to design an UWB MIMO antenna with extremely compact structures and that have a low mutual coupling [7,8]. We can say that the most critical point that must be considered while designing a MIMO antenna is to attain a low mutual coupling amid adjacent radiating elements because the MIMO antenna system performance can be strongly affected by the mutual coupling between the MIMO antenna elements, which considerably alter impedance matching, radiation efficiency, and channel capacity [9].…”

Design of a Compact UWB MIMO Antenna without Decoupling Structure

“…Two inverted C-shaped ground metal strips are placed between the two radiating elements to achieve high isolation [6]. A protruded ground plane was used in [7] to improve the isolation of the MIMO antenna.…”